Lecture Notes on BIW Fundamentals

So today in the session I will be giving you about a brief about the IW fundamentals what we follow in industry. Okay, so I want this session to be interactive. Sorry to not sorry. So yeah, because I want no problem if you're if you're fine with being interactive, that's fine. I just wanted to make sure you're fine with it. Yes, please. Yeah, because I want to understand like. you guys uh onto the same track or you have their different opinions okay so uh this is about me and i'm glad that i'm taking this session so um uh just stop before starting uh i just want to know like uh what kind of crowd we have it here is like all are from college or all are working for professional or if somebody can help me out yeah so uh so let's do this folks uh if you can in the chat box Let us know if you are either currently in your third, fourth year degree, first, second, third, or fourth year in mechanical or automotive engineering. Say first year mechanical, second year mechanical, third year mechanical, fourth year mechanical. If not, if you are currently working in the industry, say two years experience design, three years experience automotive. Yeah. And if you're searching for a job, just say graduated. Great. So I have seen, I got my answer. It's like most of them are from. college okay so great so perfect what is your understanding like uh guys is what's your understanding in biw when we call biw what is your understanding till date i have to check chat every time right body in white yes but what does that mean designing a car okay so i think uh uh we can't unmute uh people's right sorry yes uh yes so there are so many people uh we will kind of create a noise okay perfect so uh okay uh i i believe the understanding of you is like all you all of you was having a similar kind of saying skeleton of a vehicle for some body frame so one person had given a good answer is vazit faruk his body in white is the stage in automotive manufacturing in which a car body frame has been joined together that is before painting and before the motors is is a very good answer like this is the answer what i am expecting you So guys, BIW is nothing but it's a skeleton of not skeleton. It's a sheet metal components of vehicle. Okay, which has been assembled joined together. So before that, this is the outline of today's session. It's like we will be having first going with introduction, then classification, then BIW subsystems, key components, assembly process, type of joining process, total overview and credits. So this is the sequence in which we have to follow our session of the day. Okay. So yes, somebody is told, somebody told like the AIW is a skeleton which we use before painting. So we call that process a CED process. Okay. So what is CED? It's a cathodic electronic deposition process. Okay. So in which we depower entire skeleton or entire sheet metal part of the body. We call it a monocoque structure. Because after this we assemble all the engines and the other components. So in engine also we have sheet metal. But we are not calling them as a BIW component. Why? Because when we dip this component all together with the skin panel. I have just deleted the skin panel over here. With the skin panel all together we call it BIW. So BIW is a complete assembled body shell ready for painting. Ok, BIW is made of metal parts mostly steel sheet metal part and in the very expensive car we have aluminium cast brackets and the other things also. Ok, hope you guys are clear with the BIW introduction. So, when we call about BIW, we have divided it into three main segments. What are those? That is underbody platform where our chassis, engine, everything is getting mounted. Even the seats of the car. fuel tank everything is been mounted that is also been divided into three sub units engine room cabin floor where the seats are there and the rear floor where the second seat and the third seats are been closed kept that is the underbody okay and we call it engine room and in cabin room and the rear floor zone we have our fuel tank which I will explain you in the later slides how it has been placed and how it has been there okay Then we have upper body where we have cabin above the floor or whatever we have. We have in there A pillar, we have B pillar, we have C pillar, we have D pillar, we have roof structure. Everything is coming into upper body category. Then we have closer. Why we call it closer? Anything which gets closed is closer. Okay, so we have hood, it is opening and closing. Yes, it's a closer. We have doors which is opening and closing. Yes, we do call it closer. We have even fuel trunk which opens. Okay, and closes, it's closer. So all the things which opens and close we call it closer in that there is one component which is fender okay it doesn't close but the thing with fender is doesn't weld also with the components okay it's always getting bolted and it's it doesn't have any safety regulations in the car okay it's just a style feature and it has some requirements based on the functionality but it comes into closer department okay so any doubt till here you guys have yes if you have any questions in this slide or in the previous slide that the that summit spoke about please ask in the chat box okay i think there are no questions artya ask us what tailgate or lift gate is yeah i will explain you those things okay great so hood abc pillars all those things will be explained in the upcoming upcoming slides yes there is some issue with my presenting Okay, so what is upper body, what is closers and what is underbody. So this is the area which is been divided into the VIW as I told you in the previous slide it has been divided into these three areas. So what is upper body? This shell of the body which have body side outer, A pillar inside, this is the B pillar, we have C pillar, I will show you what is C pillar, what is D pillar, everything. This is the roof of the vehicle. Okay, similarly closers hood this component enclosure. Okay, this component in the closer call as fender. Okay, front door rear door hood. Okay, front door rear door tailgate. Okay, we have fuel trunk also. Okay, fuel lid. Okay. So these things are closer in upper body. What we have we have hood sorry roof body side outer. It is the main styling component and this is the biggest component in automotive vehicle. Okay. Whenever somebody will ask you what is the biggest component, the body side outer. But in this also, there is a lot of engineering. Like this segment of the car is coming into frontal crash. Okay. This segment of the car is coming into side crash and this is coming into no crash. Okay. So sometimes what we do in vehicle, we just have a two component. joining together to make a BSO. Why? Because in some area we need more strength and in some area we don't need more strength. So in that perspective we just break this components also sometimes. In Honda, in Duster if you will see it has been divided into two. In Honda it is divided into three segments. Okay so this is a kind of design strategy what company used to make to understand because in automotive we have a number of regulations. and we follow NCAP, New Car Assessment Program. In that, we have country-wise regulations. We have 10 country regulations over there, which are USA, Japan, Canada, India, China, Australia, New Zealand together, then Korean, and then European, and then Asian, consists of all this. So this is again a different topic but considering all this country regulations we used to design all our disk components. So in crash the most important aspect is underbody. So our underbody is fully designed for the crash. Because it have all the features. It have front seat here, rear seat here. It have engine compartment in this zone. It have fuel tank under this small zone. under this zone we have a spare wheels coming inside this if we have a third wheel third seat it will be coming here so spare wheel if there is a third seat the spare will not come in this area it will come bottom of the car we have the axle mounted in the bottom side of this area we have exhaust going through from the center of the tunnel which i will explain you in the later slides okay and then this area we have axle we have engine we have transmission ac unit everything whatever you see in the card in the in these blocks are being mounted in underbody so this is the biggest robust Zone of the vehicle what is upper body? It's the second robust zone of the vehicle and the area which is not very much strong. It's other closer Okay, so all together when we weights all the thing it is it comes around thousand like this The entire weight of the vehicle is something 1300 kgs Okay, if I say a normal SUV car where this all combined together gives you around 400 to 500 kgs okay and then rest of the components are different okay clear okay so till now guys you are clear with the thing or you have any doubt if you have any questions please let us know in the chat box uh with respect to upper body closures or underbody okay it looks like they are clear or cement okay great great so this is how we do our uh uh this is our biw subsystem then talking about the key components in upper body So when we are talking like somebody have asked me what is A pillar, what is B pillar, what is C pillar, D pillar. So here if you can see a bigger picture of a bigger MPV vehicle. So A pillar is the pillar which we have it here. We have B pillar here, we have C pillar here and we have D pillar here. So all together we call it a vehicle will having around D four pillars in the vehicles. can anyone say me why we need pillars in vehicle type it in the chat box uh the question is why we why do we need pillars in vehicles stability somebody said yeah support yes what else to sustain load okay very good so uh uh yes actually uh these pillars are very much required for the strength and stability at the same time we use it for having a very good stiffness toward the vehicle okay as we know for uh for these zones we need uh we have a door okay so this all are the very uh it's vacant areas okay when the loads are like uh if we consider the torsional stiffness of the vehicle how that can but is someone tell me what is torsional stiffness and carry load paths okay for carrying upper aluminum carbon steel no we are not using those kind of till now so The question is what is torsional stiffness, right? Yes. Yeah. So, Puneet Kumar says strength to resist shear force, degree to resist torsion. Okay. So, I believe like all you have your own understanding on this and I am not saying anything is wrong in here. It is correct. But you have to, I will just show you an example. Okay. Just we will consider a piece of paper. if we are going to rotate it with this axis it is all easily rotatable right okay so but if we make it a frame outside the suppose just take a consider of frame picture frame if we only twist the paper inside the picture frame it can easily rotatable but if we take the frame and we will try to twist it it won't because we had provided a stiffness throughout the boundaries okay so what stiffness and okay you will say why how it is important in uh car because when we have a car okay suppose this is a car with four wheels okay when we are driving in a twisting area like it's uh it's in a you it's kind of curving so what will happen we have two forces acting on it in one in here one in here so if we won't provide this kind of pillar what will happen stronger pillars what will happen this areas will become slightly deformed okay and the vehicle will become unstable as because we we don't have a good torsional stiffness in the vehicle so to provide strength in the vehicle and to provide a very good stiffness torsional stiffness which enhances the vehicle dynamics and the vehicle performance we have to use this kind of stiffness pillars in the vehicle okay for MPV we need 4 because we have a bigger zone from C to D which is unavoidable which we can't avoid but when we have sedan from here it goes down like this in this we don't need it because the height over here is not much okay so we only use C pillar upto C pillar when we have hatchback we sometimes don't need a C pillar also we just manage this with A and B pillar okay so this is how the pillar designs takes place in the vehicle. All clear? Or anyone have any doubt in pillars? These are all the components in vehicle. So this is the A pillar, this is the B pillar component 2, this is the C pillar component 3 and D pillar we don't have it here, I can show it in here. Okay, rear quatra panel is this panel. Okay, we have it in here and here inside quatra panel will be there inside this panel and this is the BSO, body side inner outer. Okay, and this is the part which reinforce it from the inside. it have rear quarter panel okay seven is the roof structure this one then roof Bose is here we have it here here front middle rear and this also depends on the length of the car if the length of the car is huge okay if the roof is huge then we have to divide it more okay again the factor is same torsional stiffness and the bow the roof is not welded with the vehicle it is sometimes welded laser welded and in this area it has to be mastic with the reinforcements what we have it in here ok so we need more roof reinforcers in this part of the vehicle then we have cantrail ok this is the cantrail ok you can see it in here ok we have rear wheel house ok that is somewhere here inside because here wheel housing we call it because inside this only the wheel movement will be there and the suspension also will be mounted in here okay then we have rear drain channel which is used to drop the water whenever it's coming it's raining suppose and all the waters are coming down here all because the vehicle is moving all due to the aerodynamic all the water will be coming and it should not enter into passenger compartment so we have this rain drip channel we used inside the vehicle so it will collect all the water and it will go down from the sides it will not come inside the like passenger zone okay and then we have a combi light lamp panel so in this lamp panel other than this we have a big cutout which we call it a body exhaust a car body exhaust okay we have two kind of exhaust one is the exhaust which is coming from the engine one is inside volume volume inside the volume of cabin passenger we have one more exhaust okay can anyone say like why we need this exhaust sorry uh i think they are answering that in the chat box somebody have told dampening somebody have to remove the co2 i i'm not saying it from the exhaust i'm saying it's from the body uh volume okay ventilation like a ventilation very good which type of coating used for cars to withstand environmental condition okay Raju Yadulapalli I will answer you this question after the session when we are answering all the questions because of ventilation to remove heat to release the pressure yes then Akash Shodri who answered yes this is the answer what I am expecting to release the pressure inside okay suppose we have a closed structure closed packed chamber okay and if we have a very good ceilings and all the air will not come out and suppose when air conditioning is going on everything is going on so whenever we close the door okay as the air come inside this is so much huge it won't allow us the door to get closed okay because it it will reflect but But due to that we have this kind of small small exhaust inside the vehicle which releases this airs okay and doesn't create this huge pressure for the doors to get locked. So this is the reason and again second reason is we have to recirculate the air inside the car one is with the air conditioning we are doing another is with this kind of exhaust so that the PM model. particulate matter inside the car should not be huge okay so this is the reason why we use it so actually you are right okay so this is about upper body if anyone have any doubt related to upper body they can ask and then we will switch to closers clear material of upper body okay personal stiffness and material of what is can train okay and get what you said about second exhaust okay okay so we will answer one by one surya can you help me with the portions uh sequence okay so sorry sorry to involve you no no no okay so uh material of upper body is a very important uh aspect okay so what we have to understand is like what what kind of uh purpose this upper body solves okay so we in vehicle mostly we use steel okay so in steel we have lot of grades with we call it lesser yield grade and higher yield grade okay so lesser is something around 200 to 220 mpa and higher is around 880 mpa okay we use this kind of steels in the car but now what is important is like if roof if suppose we consider roof roof is not coming in any crash requirement okay no crash requirement comes under roof there is something coming for 2022 for that we are considering but that is again for the pillars not for the roof okay so for roof we always go for the lower yield uh steel okay but if you will see a pillar b pillar okay so these components are directly coming under go under side impact test. Okay, so inside impact test and the pole impact test this component are directly coming into play. So we can't use 220 to 220 because the yield the crash pulse what is getting generated it's more than 220 it's around 350 to 400. So what we do in this area we try to use something around 600 MPST okay and that also there is a catch. okay the crash occurs only in this part of the vehicle okay up to this zone of the vehicle okay so what we do we we make a laser welding for b pillar okay so what we will do suppose this is b pillar of the car okay so what we do till here we will use 600 mpa okay or higher thickness higher thickness and above this we will use again 200 to 300 m okay why we use this because this is a very expensive steel okay so we if we use it throughout the component it will make it a expensive part okay so what we do we just do it uh like we just trim the part into two components second for 600 mpa uh forming is a challenge okay forming is kind of a manufacturing process to give a sheet to this form Okay, so this is again a different subject altogether. For this, what we used to do, we do hot stamping. Okay, hot stamping is something in which we take the steel into crystallization temperature, something around 800 degree centigrade. We heat it and then we form it. So again, if we do it for a bigger component, the part getting colder is more time off. It will take more time. okay and for this small component it will take lesser time so that is also one of the reason we go with two kind of stiffness in this area all clear so that is again how we select the steel here BSO is a part which doesn't help in the crash okay so we used again the lesser yield but Cantrell is a component inside okay Cantrell is a component which is inside this area which which is with the aerodynamic of the car we use it i think this is also one of the questions somebody's asked what is cantrel and why you use it so if i share a whiteboard yeah can you see my can like whiteboard yes yes okay okay so suppose this is the car okay uh somebody asked me what is canter okay so for that sorry sketch okay so suppose this is the car okay okay so we know our driver is sitting here right this is the position of the driver sitting in here in the seat okay suppose this is the position suppose any crash is happening from the front so this can't well before it was something like this in the previous uh if you see old car these are not much aerodynamic so nowadays the car become more aerodynamic okay just to take the load uh air in a very well manner so that the downward force will be good uh the lift force will be uh good there won't be any drag force uh lesser drag force so that the efficiency will enhance okay so then but what is the challenge in this kind of thing if you will see this this structure whenever the crash will happen the driver head is well safe from the top from the here and from here okay it's none nowhere near to the these kind of pillars but now what happened when we had this aerodynamical consideration what we did we bought this pillar near to the driver's head zone okay so now this pillar have to be very much strength there because if the crash should happen it should not come in here so what we do in this area we make a program deformation suppose a deformation is happening whenever the crash is occurring and the deformation is coming in here we make our crash in such a way the deformation will always happen in this direction means this will break in this manner not in this manner. Okay, that's why we call it here a program deformation. So we give a crack and whatever load will come the crack will always come in this area. Okay, so can trail why we use can trail to this is a one ribbon which takes vehicle from front to the end and why is it in this shape now because to consider as we are considering aerodynamic structure, so this has to be here. okay in here and the glasses will be also coming and resting on the canter I hope your doubt for canter is done so there is one more question someone have asked me that is regarding okay a build up a body with 3d printer will it have more strength but what material you are using again it's a very expensive and time-taking process one thought process is since there will be questions to the topic that you also teach what we can do is for those kind of questions we can keep it at the end so that your flow kind of uh goes fine okay sure because i i want uh them to get cleared in every area like yeah absolutely absolutely so for the for the questions that they have about these topics that you teach yeah that i am answering uh if they are questioning something apart from the topic guys uh please make it sure like we will be doing in the end of the session so that i can answer you in uh very well manner okay so right now if i'm asking you some question try to answer in that way in that zone only okay so i hope uh upper body question uh thing is clear with you then we have under body uh sorry closers as i have told you the components which are getting closed are closer but we have a separate part which is fender why fender is not inside upper body and under body because it is a part which is not been welded into the car it is always been bolted into the car okay so underbody zone all together it comes as a weld component upper body comes as a weld component then they will fit all this component inside the car that's why we call all these closers okay same applies for fender but it doesn't open and closes it always gets closed it never get opens if we want to open then that is a different criteria so this is the component hood bonnet assembly we call this hood second is lateral door and front door that is the this one the frontal door this is the rear door uh fourth one is the trunk uh fuel door or trunk lead we call it okay sorry fuel lead we call it trunk we call for doors uh tailgate okay and then fender is the fifth one the balloon got missed okay so this is uh this is about fender Somebody have asked me, I have just seen in the questionnaire, somebody is asking what is FMVSS for hood. Okay, so first you have to understand what is FMVSS. It's a United States law for the crash. Okay, for hood, yes, we have pedestrian head impact, but it have different consideration. US is the only country which don't have a head impact initially, but now they have to integrate it. Okay. So that is something different. OK, so these are the components. Whenever we design our doors, we have to take a lot of things into consideration because we always open and closes the door. OK, so we whenever we design and when we test, so we close the door like a lakh times. One lakh eight thousand is the cycle time for a door to open and close. OK, similarly, it is for the rear door. This is not for one lakh. It is for some sixty four thousand. and 48000 times this is how the testing for the doors have been done so in this testing what we see the doors should not get uh bended it not that deteriorated it should not bend it should not deteriorate and it should not break anywhere okay with this one lakh eight thousand cycles so this is what kind of test we do for the doors the similar kind of test we do for hood but the numbers are not huge uh like one lakh It is around 30,000 or 40,000 for some of the regulations. okay because we open doors more frequently than the hood okay in this also we have primary lock secondary lock okay so uh anyone know what is secondary lock and why we use it no uh this is not related to child lock suppose you are driving if we we have a secondary lock if whoever driving a car they might be knowing like when we open a bonnet it won't open full okay it will just the primary lock will be unengaged and the secondary rock is always a manual lock it's it should not be a automatic or it's a motored one why because suppose you are driving in a speed of 120 kmph okay suppose you are driving your car in a high speed okay and all the aerodynamic effect is happening in here and suddenly by mistake you triggered your hand on this latch area for the hood So this will all due to the air effect it will open like this. Okay. So it will open. So what will happen you will have a like your visionary will be getting affected and you may crash in your vehicle somewhere. So all due to this reason we always have a secondary lock in here which is only accessible by the hands. Okay. So suppose you are driving in a high speed and you are by accident your hood. the primary lock get disengaged this will not open it will still be intact okay but you will feel some vibrations in this area which will alarm you that okay this area is nowadays we have a digital cluster it shows okay your bonnet primary lock is open okay so that you can open okay that is the only reason why we have still a manual locking in this area not a electronic locking for any kind of car okay that is what why we use uh hood uh like uh in that purpose second is like all the closer components uh the components are not a very uh like they are not into lot of uh crash regulations okay we have some regulation related to pedestrian impact but not related to high crash like kind of we call like uh the load absorbing and all but that is for hood tender also doesn't absorb any load hood also doesn't absorb any load but with hood what we have we again as i explained you about the can trail okay how the deformation happens in hood also what we do we give a program deformation so that whenever the impact will happen the program deformation will be like this okay so that this complete hood assembly should not bend and go into this passenger zone okay suppose this is okay suppose this is my car okay this is my car and this is my hood okay so if suppose the crash will happen and and with any pulse if this goes back in here and we hit the windshield and all or go inside but what we do as a designer we give a compulse zone in here so that whenever the crash happen and this engage it will not break everything on the vehicle of the hood. Okay, this areas and all. So what it will do it will break in this area as we planned that deformation as a designer. Okay, so hood will absorb whatever energy it will have it will be there. It will absorb and it will break in here so that the load will not be transferred from here to any other part of the hood. Okay, so that it won't go back and hit anywhere of the zone and it won't absorb the load then all the load will be absorbed by the underbody okay so that is the second area where you will see a program deformation in the vehicle okay who in doors we have for frontal crash because as we know the load is traveling from here front okay i will color it from the different color okay yellow you Suppose the load is coming like this and from here it has to transfer in all part of the vehicle. Okay, we have B pillar here. Okay, we have A pillar here. We have canter here and we have the bottom seal here. Okay, so when the load is coming the first point of contact is from this area the side member and this side member from the center it takes it till the rear of the car but from here from the side end of the car it transfer it from here top from here it goes down and from a pillar to b pillar we have one skirt We call it skirt or stiffener rod in the door. Okay inside somewhere here. Okay, what it do do it like it takes all the energy and transfer it to B pillar and from B pillar. We have the same kind of rod in here which transfer it from B pillar to C pillar. So that is how the load is been transferred from front to the end of the cart with the help of this kind of designs. Okay. Similarly, we will be having one more rod we call is G bar or anti-intrusion beam. So it is also like this in here so that whenever the impact is coming from the front, all the load will be going in front A pillar and the B pillar of the car, not inside the passenger area. So that is how this door panels comes into play. Rear gate, tailgate is important. Now we have lot of crash regulations coming for rear also. China and USA have a rear crash with 80 kmph speed. Okay. So in that area also the criteria are this should not break and go inside. Okay. So that the designs are very much robust in this areas. Okay. So this is all about the closer assembly. If anyone have any doubt related to closer can ask me now. Only related to closer. somebody is asking which type of sensors used for to know close and open of the door it's a touch sensor and the impact sensors we have it okay and that is on and off sensor it's not a huge sensor and it's a very less cost sensors okay no doubt what is fender i have already explained you what is fender this component we call it fender so you want to know more about fender okay So the fender, okay, see why the fender is bolted because in underbody, okay, if you can see, okay, so this is the skeleton of the bottom skeleton of the body, okay, this will come and then upper body will come and then fender is been mounted half in here and half in underbody. It is bolted in here as well and in upper body as well. So we can't. bring that fender with any of this component. Okay, so that's the reason we can't weld it with some area so that we have to weld it in again different area. So we put this fender always as a bolted object. And the second thing is whenever the crash happens folder this fender gets deformed very easily. If it will be welded, it is very expensive. It's an expensive process to like repair it. but if it is bolted you can easily unbolt it and you can repair it. Okay and third thing is it is not a load carrying object. Okay, only purpose of this fender is for styling and for the wheel aperture like wheel should come in and come out that is the only thing we need it for fender. Okay, so we don't need it to be very constraint lot of constraint manner we don't need it so we don't need any welding and all in here it's just a one component we even don't have fender reinforcement for wood we have a hood reinforcer inside uh for door also we have a door reinforcement inside tailgate also we have an enforcer but for fender we don't have an import even for trunks also we need we have an all because this we don't need any statical stiffness stiffness of this component we don't need any internal stiffener or internal components in this area. Okay, so I guess it is clear what could be the generic design tolerance limit for these parts. So tolerance of these parts are again for the surface tolerance we always use monon more than 0.5 mm. Okay, for the edge tolerance it should not be more than 0.1 mm. Okay. for the holes and all it is we have a general tolerance for all the kind of hole standards okay only for surface and the lines i have already told you what is the tolerance level we maintain okay which previous picture we don't have rear side fender in car okay so fuel door it's a it's a component like we we we have this filter with a inner reinforcement and the hinge assembly we always have a positive locking in here which locks and unlocks with the sensor so the fuel the gap and flush at the fuel lead is very much important because if the gap in flush is not been maintained it is virtually it can be visible with any of the customer or any defects in this area or any different sizing or different flushing in this area so this area is very much critical second important aspect in fuel door is like it should always flush with the outer panel so that the aerodynamical drag should not affect this zone. So that is the reason this is a very important aspect of the car. The water should not get stick here because we have unprotected zone inside which get rusted if it is not well designed. So this is how. So what is gap and flush I can explain you those area. Suppose this is door. Okay, it's a BSO. and this is a fuel trunk. So we always maintain a negative flush. What is negative flush of 0.5 mm means this body side outer component will be in higher side and this one is always in the negative side. So that whenever the water comes from here it should not enter in here. From here it goes and here it comes out. So it is sometime also tilted in this manner. This one. Okay, so how it is been from here minus 0.5 and here it is plus 0.5. Okay, sorry 0.5 so that whatever the water comes from here comes here and goes here. Okay, so this is sometimes we always maintain 00 type of plus but that is not possible. So we always keep a tolerance of mine 0 to minus 0.5 0.5. okay not more than that that is the tolerance limit we maintain in this kind of zones so uh this is all about closures so we will move to our next area that is underbody okay uh anyone if anyone have any doubt they can ask me or we'll move to the next area we have any question mr clear thank you i will answer these kinds of questions later after the training has been done okay uh forces act on closures okay what is the aerodynamic forces acts on the closer while moving when the component is moving when we have a when we are closing the component we have a force the like closing force and opening for closing efforts okay when we drop our like food from when we unlock it and drop those are the forces acting on closers those kind and the in static condition these are the forces and when in dynamic condition aerodynamic is the only thing and sometimes if it rains and those are the forces which is acting on closures defining fender you showed one diagram okay okay we have been talking about underbody so this is the main area of vehicle which is not related to the styling of the vehicle which is related to the performance of the week okay Why because all the crash loads have to be absorbed from in underbody. Okay, and all the things like the vehicle the seat mounting also is in the underbody. Okay, so related to any safety all the even the steering wheels everything is been mounted in underbody part of the car and it is the only component. It is the only area which have more number of component than any of the other areas. Okay. it have somewhere around 120 to 140 components where in others it have 60 to 70 component in like upper body and 40 to 50 component in closer okay but in underbody we have 120 to 140 components okay so there are huge components and a huge parts also which is being used in underbody so i have just shown like for what all are the 15 areas we have shotgun which is here which comes from a pillar okay which takes the load uh for uh which takes the load to the side of the vehicles okay the uh bot uh like uh this area the front uh this area uh front wheelhouse and the bottom traverse member this takes the load to the bottom part of the vehicle and shotgun takes the load to the sides of the vehicle okay second is front wheel housing okay this is the front wheel housing below this we have our wheels okay third is a suspension tower okay shock tower we call it in automotive also so that all the load will be this is a very uh robust area because lot of loads of the suspension will be coming on this area code is dash and firewall that is this area which you can see so dash is the one of the biggest component in uh underbody because it have lot of mounting it have mounting for your CCB is like cross carbine where all your dashboard your steering column everything will be bolted steering is been bolted to A pillar to A pillar and then inside in the dashboard all your like brake booster pedals everything will be it is mounted in like CCB and the passing is been gone through dash panel okay steering passing is also going through dash panel it is also a heat chamber uh heat shield because it won't allow the heat coming from engine to the compartment zone okay it also have our refrigeration unit coming into from here and mounted in here okay so that is all about dash panel call it up panel is uh here uh where we used to uh like uh the call it off panel is here yes because it is also the water box area and call it up we call it because the like the windshield has been placed in this area okay and even the whatever whatever water is coming from the windshield is getting collected in here and going out of the vehicle okay so this is all about uh uh call top this is how the water flows out of the vehicle we have a hole over here so that the water will be coming out from the bottom outside of the car. Okay. So six part is the floor assembly floor assembly doesn't have any loads. So we put it in a very lesser thickness of 0.6 mm. It always only carry the load of leg and other things. Otherwise all the load will be taken by this member cross member where the seat is being welded. Okay. So this is a stiff area. This one is a stiff area and this side is a stiff area. and in between where we using our sheet panel those are not a very much higher stiffener stiff tail okay so this is about floor assembly central floor center floor is also here uh rear floor is somewhere here okay this one okay here we used to put our uh okay first i will clear okay this is the central floor zone okay this one this is the rear floor zone okay So this even protect the fuel tank from the top. Okay. And this one have spare wheel inside the vehicle. Okay. So we have both kind of provision inside the car. So that whenever the fuel should not come inside the cabin compartment zone. And this wheel. And for this wheel there are two types of provisions. Sometimes it comes inside the car. And sometimes it come bottom part of the car. Okay. that depends if we have suppose you will take examples of duster and all we don't have it in here we have it in the bottom part of the area but if you will take any sedan car we have it inside in here in hatchback cars also we have it in some time we have it for SUVs also okay so that is again a strategy for a companies like how they want to provide and where they want to provide the spare wheels okay so floor cross members are this kind of members where our sheet is getting bolted so seat is getting bolted in here here that is for the left seat okay here and here that is for the right seat and here from this zone to this zone this is for the rear seat bench okay this is how the seat is been mounted we have a time constraint so i can't show you exactly where and where so i'll show you later okay floor tunnel why we have a floor tunnel so that the 4x4 rod and 4x2 drive shaft can pass it from here at the same time for 4x2 the exhaust in 4x4 drives out as well as the exhaust line should pass from here and 4x2 like two wheel drive this will pass only the exhaust line okay so that is why we have this tunnel over here okay Then we have a kicker panel here because why we call it a kicker panel because below this after this we have a fuel tank or the battery in the new generation car. We put it in here and the leg should not go below this behind this zone. OK, that's why we keep it as we say is a kick off panel. OK, so that the leg of the rear passenger should not go below this line. okay so that is about this zone then we have sill panel that are the two stronger line of stiffener going from the side component of the car like this one and that side also it travels from here to up to the end of the car okay cab ring panel is again the same one here what i have explained you rear apron is one where the tailgate comes and get fitted okay so if we have that apron so where the lock of the tail there is been getting engaged okay and then front or rear seat support member so for seat we used to have the support members so for that we we have one extra brackets in those areas okay so that is all about components in biw so till now if you have any doubts we i'll I am happy to clear you and then we will go to the different zone. Okay. That is how the assembly process has been done and how the other. So till now if you have any question you can ask. Yes. Powertrain comes under underbody. Do design changes according to material. Yes. It does change. Explain on tailgate and that is already considered explained. Okay. Okay. Great. Yes. It's a huge area. BIW so yes okay somebody asked me about shotgun okay define a and rear uproar okay so what is shotgun suppose if I will okay you can see my whiteboard can somebody answer so suppose this is the structure of the car okay so this is two cross members of the car okay which is going till the rear end of the vehicle vehicle. Okay. So this is the center part of the vehicle. Okay. Suppose I am explaining in that way. Okay. So this is about the center load. So this is the first part which takes all the load from the impact from the front. Okay. It even have the engine mounted in these two blocks also only. So what the underbody is fully designed as per the for the crash. but upper body is not been designed more into crash so but it should also absorb the energy so what we have done we have used a second member okay which will also absorb the crash when this fills up to this area okay then only this member will start absorbing okay so when the second absorbing area we call it shotgun okay So, if I'll explain in here, so you can see this golden part from where it's starting. Okay. So, this is from here, the second load impact will be absorbed. That will be absorbed to upper body. Okay. Center area and the side of the car. But this one, these golden areas. this one this will absorb the first load of the impact okay and will transfer to this till this areas in the center way this goes from bottom till here okay so this shotgun is here is to deliver the force from here to the top of the car to the bottom of the car and to the center of the car that is why we use this shotgun okay second is apron what is apron is like we it is a rear filler in this area suppose here we don't have any apron but in here we have an apron okay what will happen you you whenever you will open your tailgate you will see one panel okay in which there is a gap where the latch is there okay which will get an hooked which will get hooked with the tailgate okay so that latch should get locked okay with this area so for that purpose we use the rear apron okay i hope it is clear clear the one who have asked about shotgun and uh fender oh sorry apron okay clear so kick kick panel okay so you guys are making me revise all this area okay okay kick panel is the one okay suppose here if i take a section in this area so this is the our base plate of the card and this is the kick panel i will explain in here okay so suppose this is the base okay and this is the kick panel and this is how it goes in the vent our seat has been placed something like this okay and the leg is coming here in this way okay so this is how the leg leg is been placed okay so if person leg is going below this zone somewhere suppose the kick panel is not messing with it and it will be here so what will happen the person leg can truck and he can fall coming out of the vehicle so for that reason what we do we just have a kick panel in here so that the person leg will not go behind this line okay this is the brief explanation of kick panel so that the whenever it will kick it won't go behind this it's a human physics we have to understand okay so this is a person should not fall when he is coming out of the car you this doesn't happen for the front passenger because in front passenger we have lot of space okay for the rear passenger we have some space constraint okay for that reason we used to provide this kind of provision okay that's the reason we call it kick panel uh somebody have asked me about dash area right so dash is something like this is the dash okay all the ac uh suppose these are the other rod okay this is the steering going inside the dash this is So all the heat panel no heat should come inside this even whatever the load or pointing things it should not make this dash deform in such a way that it will damage the passenger. So dash is that's why it's a very important aspect and it is very well reinforced in all the area so that the dash intrusion is the car will be minimal okay it should not be high. it should be always minimal okay that is about all this area so that's it about component of the cars okay i don't have any in the individual pictures right now okay so now is we have to understand how is the assembly process inside a company okay like how it is been done so uh one is uh one as area is our body assembly which i will explain you how it has been done but before body assembly all our component is been made out of sheet metal ok so this is the sequence how a car is been made inside the factory first a sheet metal will be coming ok and it will be getting stamped inside the press shop ok then that components have been gone is going to body assembly shop where we use to weld it all together so to make an assembly okay then this will call as a body in white components then it will go to paint department okay where it will get painted then trims and chassis area will be coming okay where all the plastic trims will be fitted into the vehicle plastic trims seat and all things are been fitted into the vehicles okay then TNC chassis where the the bottom chassis parts the axles and all parts have been bolted together joined together and it is also being tested in this zone how the suspension testing the rolling testing those kind of tests not for all the vehicle for all the vehicle we will be having that test and we have separate in one stock will take out some of the vehicle and we have a rig test also okay we have a small test rig where we will test the vehicle the first go then we have an inspection area well we inspect with a lot of quality inspectors which will see all the smaller smaller defects if there is any paint defect so or any dent on any other panel the car will get rejected it will not be getting sim okay so it should clear all this zone to get sim okay so this is how the car has been made first stamping then the body assembly where all the components will be bolted and welded then paint After the paint, all the supplied parts like glass, the windows, fitments and all, the seats, the plastic component, mats, roof mats. everything will be fitted okay then tnc where the chassis uh the engine parts are being fitted then the inspection and then the car is gone for shipping okay this is the sequence for uh the car to be manufactured but in the varied shop how it is been divided as i have already told you the component of the car is been divided into three areas one is underbody second is closer and third is upper body Okay, so in underbody we have three areas as I told you front area engine compartment area if you remember I have explained in you in here engine room cabin floor and the rear floor okay. So this is how the assembly looks okay. So this is the engine area. So this is the complete assembly and these are the sub assembly which will get welded together to make this. This is the cabin area for the front. this is how it is all together and welded to make this then this is the rear floor how it has been welded a skeleton and the surface all together so this all together one two three combine to make a complete underbody okay then we have body side okay that is with body side outer body side inner panel then quadracore panel all together when we assemble we make a body side outer assembly for the side and for the right side is different roof altogether will make an assembly okay and then the tail altogether will make one assembly okay so all wind will fit it is coming up to this skeleton zone okay till this skeleton zone first is front unit this is the example of renault logi in which I have worked this is how the front unit will come then the front and middle then the rear floor then with the side panel want I can sorry zoom this area then the sides how it is been used this this area is been welded in here and this reinforcement will is been welded okay all together then the roof is been bolted or welded whatever it is okay and then all the closures coming so in hood also we have small small component hood outer hood inner and the reinforcements for the latch and the hinges okay for door if you will see front door we have anti-inclusion beam skirts front beam outer panel sash type panel inner panel all together we make a body door outer okay similarly we do the trunk lead with the outer panel and the inner panel reinforcer with all the hinge reinforcement and the latch enforcement so all together when we complete our biw from here it goes up to here the assembly occurs in this progress so any doubt in this two assembly sequence anyone now i will explain you about the welding process in upcoming slides maybe tomorrow not today yes i will explain you about hemming also anyone have any question related to these two assembly uh area clear all clear okay great great so chassis fitted in tnc uh chassis okay chassis you mean the engine and complete engine suspension axle all together will be fitted in TNC yes first one is engine fuel tank comes in this zone ok in the rear floor as I have explained in the this zone of the vehicle is where the fuel tank is been bolted ok here under the front of this area ok I can explain in here also in this zone okay this outlet which you see a small hole in here that is for the fuel pump okay so that you can like service your full pump if there is any issue no biw contains all the sheet metal parts before painting this this is all biw components till here okay and this has been uh like painted and then sometimes it is getting dismantled all the doors will be getting dismantled and they have to fit a lot of things inside the door so after the paint they dismantle it and then t t and c they will assemble it again okay software we use a lot of software nx uh like depends on company what what company is using some company use next some company use scatia some company use solidworks uh so it depends on company so this is all about all about assembly process so I will show you some of the videos related to part and manufacturing and assembly process and then rest of the things we will be discussing on tomorrow maybe okay you can see my screen guys can someone confirm okay you can see the video running youtube okay great so uh so if you can see this is a complete car as i have explained you these are all the classes surfaces uh in the area which is been given by our styling team to us from which we extract the complete car okay roof panel body side panel fender panel hood panel hood inner panel and the other areas okay tailgate tailgate panel front door panel okay front door inner panel is also there okay can you hear any music no right i can't i can't hear it hello i i think i don't have access to music i i can't play the music how can i help i i don't know but uh when i'm playing before it have a sound but now i can't get the sound i don't think you can share a sound from your screen on you might not share oh okay okay yes yes share sound option is there yeah thank you thank you Now people can you hear it? Okay. There's no sound. You can only see the video. Okay, leave it then. I think there are some audio issue I have to deal with my mics and all. Okay, there is no such informatics sound in here. It's just a music to entertain you guys. Okay. Again, so these are the areas like as I have explained you, so you can go through with this video also, which will say this is again where the spare will be there. These are the shock tower, front side rails, which absorb all the load and transfer it to back outside of the vehicle. Tunnel, which takes the load from the end at the same time. It has an envelope for our exhaust passing and the drive shaft passing. So this is all the components, it's a rear shock tower, rear sheet panel, okay, heel board or the kick off wall what we have explained. Dash crossmember is for the dash reinforcement, okay. Rear back panel is for the sedan cars most of the time we have it, we don't have it for our hatchback and this one. Okay, so this rear back panel we have it for apron also, okay. and in the sedan car if you behind the seat we have one panel area also that is also be said as rear back panel okay so this is all about the components you can see inside the car okay this is upper body okay B pillar B pillar inner B pillar is again I have as I have explained you it has been also used we cut the part and we use in for two variants D pillar how it has been used C pillar outer side sill that is for the side crash things and all okay closers these are the complete inside enforcement this is a window frame at the same time sash frame also door waste beam is used to send the energy from here to at the back also okay anti-intrusion it's for the side crash we use this part okay crash management system this rear bumper and front bumper have been used for some heavy related crash okay or pedestrian bumper some country have some strict regulation suppose europe and us have a rcar related concerns so for rcar if the car is hitting with the speed of 10 kmph none of the area should be affected unless only this part should get affected okay for that we use this bumpers in the front and the rear these are the steel bumpers which comes be after the plastic bumper and the absorbers inside the car this is the cross car beam which holds everything like the steering the pedals ac air conditioning areas everything of the car is been like in the dashboard everything whatever you see is been assembled in this crosscar beam okay But that is not a battery boxes is in this underbody central area below the car unit below the underbody unit the sheet unit. Okay, so we used to produce this is how the painting process is been done. Okay, this is all about the parts. Okay, the manufacturing process is this. This is how the stamping is happening inside the car for the part components okay so this is the tool uh punch and die which we use in the industry okay to make our component inside this we'll put a small small sheets and we'll get our form component they have loaded the sheet metal inside this sheet and this die ok so this is the die how it is been working how the load is been acting on the component i was telling you guys about the piyosa so you can see how the piyosa looks Okay, first strike of the car of the BSO. So in BSO we generally have two strikes. One first strike, one the second strike and then we have piercing operation then we have trimming operation. after first forming so this is all related to the manufacturing how it has been done in automotive and this is the assembly process video. Good grammar and spelling are important, but if you want to write essays that inspire, messages that forge brighter connections, and email. Car doors have come a long way over the last century. So you guys can see this car door video, how the manufacturing has been done. I'll mute the video. Okay, I will mute the video. Okay. so guys can you see my video of the car door how it's made cardo okay great okay so you can see this uh i have just kept one ppt uh one video for this how it has been made okay the car door so uh it's from the rolled sheet it is it is it has been cut and as a component and see how it has been kept inside the tool and this is how it will be formed okay so this is the first draw it has been made okay you can see okay now two two lh and rh has been divided into and it's been cut uh they have separated it with the trim operation and now they have all the forming uh piercing operation they will be performing in this okay so we have now both doors LH and RH doors so the quality inspector is inspecting all the roughness and all they will say so this is how they will do this is the window frame the top frame this is the front reinforcement where the hinge in all will be fitted this is the rear inner panel of the door assembly okay and this is how they are building it this is a spot robotic welding process we had we even have a like manual process of welding also this is an anti-intuition beam and this is the upper vest okay that is used to transfer the load from front to the end of the car okay and then they will put this again it's a robotic welding this is how the uh arc this spot welding they are doing for the components okay this is the mastic provision adhesive provision how they are providing okay for hemming operation now the outer panel of the door and the inner panel of the door it is not been getting welded it is been attached together adhesive why it is not getting welded because after the weld it always leaves a mark okay which is not acceptable by customer by visible they should not see any welding marks on this kind of a surfaces so that that's the only reason we used to do adhesive we used to provide adhesive okay in this areas because and even though adhesive is an expensive process but all because it have a visionary impact in the car and the customer directly can see it okay we use to provide this kind of adhesives in the car okay okay so you can see this is how the assembly for all the biw component is is been done in the door door panel and this is how the TNC in TNC of doors how everything is been fitted okay so this is how the handlebar is been fitted this is the chrome fittings at the top this is how the windows are be fitted okay so you will see on the inner plastic IP and all other things glasses how it is all been fitted together you can see it in this video This is the rail for the windows to move. This will be moving in this way only. This is a side mirror. Side mirror sometimes be fitted in the body. This is the complete IP mixed with soft and hard plastic. Again it's a different area and how they are testing the functionality of the windows and all and this is how the door SMB has been completed. okay and door assembly is also getting fitted in TNC of the car okay after the paint the door assembly comes out of the car and after this all the seat and all the dashboards everything is been fitted they assemble this doors in the car clear this is how they do hood and this is their what they are checking is the gap and flush so the gap and flush should be all equal okay they are checking this uh it should not have any impact okay so this is the complete tour of uh how it has been made okay so uh uh one last video i will be playing for today is like animation of body and white assembly how it is being done Okay, you can see my screen. Okay, yes. Okay, so this is how all the component is being assembled. Okay, this is only the rear area. This is the front area. This member is only the member which is transferring all the loads. It's for the sedan car. Looks like a sedan car. Yes, because they have a separate member in here. Okay, that is only been used in the sedan car. this is all the components which have been used in biw bso roof members and all some bottom tray kind of things where we use to keep our spare components and all so this is a very expensive unit of the car expensive car okay it's something like bentley alpine so they are using for different different kind of uh more members it's a Aston Martin sorry so they are using different different members inside the car okay which is not been used like some here okay this is not this enhances more torsional stiffness because the vehicle have more dynamics and the higher speed okay so it should not get deteriorated that's why they have more stiffener agent in this area sometimes they use different materials in these zones they use more yield component like sometimes they use magnesium sometimes they use aluminium with alloyed casted aluminium also okay so all together they used to make this kind of zones so that's it for today

So today in the session I will be giving you about a brief about the IW fundamentals what we follow in industry. Okay, so I want this session to be interactive. Sorry to not sorry.

So yeah, because I want no problem if you're if you're fine with being interactive, that's fine. I just wanted to make sure you're fine with it. Yes, please.

Yeah, because I want to understand like. you guys uh onto the same track or you have their different opinions okay so uh this is about me and i'm glad that i'm taking this session so um uh just stop before starting uh i just want to know like uh what kind of crowd we have it here is like all are from college or all are working for professional or if somebody can help me out yeah so uh so let's do this folks uh if you can in the chat box Let us know if you are either currently in your third, fourth year degree, first, second, third, or fourth year in mechanical or automotive engineering. Say first year mechanical, second year mechanical, third year mechanical, fourth year mechanical.

If not, if you are currently working in the industry, say two years experience design, three years experience automotive. Yeah. And if you're searching for a job, just say graduated. Great.

So I have seen, I got my answer. It's like most of them are from. college okay so great so perfect what is your understanding like uh guys is what's your understanding in biw when we call biw what is your understanding till date i have to check chat every time right body in white yes but what does that mean designing a car okay so i think uh uh we can't unmute uh people's right sorry yes uh yes so there are so many people uh we will kind of create a noise okay perfect so uh okay uh i i believe the understanding of you is like all you all of you was having a similar kind of saying skeleton of a vehicle for some body frame so one person had given a good answer is vazit faruk his body in white is the stage in automotive manufacturing in which a car body frame has been joined together that is before painting and before the motors is is a very good answer like this is the answer what i am expecting you So guys, BIW is nothing but it's a skeleton of not skeleton.

It's a sheet metal components of vehicle. Okay, which has been assembled joined together. So before that, this is the outline of today's session. It's like we will be having first going with introduction, then classification, then BIW subsystems, key components, assembly process, type of joining process, total overview and credits. So this is the sequence in which we have to follow our session of the day.

Okay. So yes, somebody is told, somebody told like the AIW is a skeleton which we use before painting. So we call that process a CED process. Okay. So what is CED?

It's a cathodic electronic deposition process. Okay. So in which we depower entire skeleton or entire sheet metal part of the body. We call it a monocoque structure. Because after this we assemble all the engines and the other components.

So in engine also we have sheet metal. But we are not calling them as a BIW component. Why? Because when we dip this component all together with the skin panel.

I have just deleted the skin panel over here. With the skin panel all together we call it BIW. So BIW is a complete assembled body shell ready for painting.

Ok, BIW is made of metal parts mostly steel sheet metal part and in the very expensive car we have aluminium cast brackets and the other things also. Ok, hope you guys are clear with the BIW introduction. So, when we call about BIW, we have divided it into three main segments.

What are those? That is underbody platform where our chassis, engine, everything is getting mounted. Even the seats of the car. fuel tank everything is been mounted that is also been divided into three sub units engine room cabin floor where the seats are there and the rear floor where the second seat and the third seats are been closed kept that is the underbody okay and we call it engine room and in cabin room and the rear floor zone we have our fuel tank which I will explain you in the later slides how it has been placed and how it has been there okay Then we have upper body where we have cabin above the floor or whatever we have.

We have in there A pillar, we have B pillar, we have C pillar, we have D pillar, we have roof structure. Everything is coming into upper body category. Then we have closer. Why we call it closer?

Anything which gets closed is closer. Okay, so we have hood, it is opening and closing. Yes, it's a closer. We have doors which is opening and closing.

Yes, we do call it closer. We have even fuel trunk which opens. Okay, and closes, it's closer.

So all the things which opens and close we call it closer in that there is one component which is fender okay it doesn't close but the thing with fender is doesn't weld also with the components okay it's always getting bolted and it's it doesn't have any safety regulations in the car okay it's just a style feature and it has some requirements based on the functionality but it comes into closer department okay so any doubt till here you guys have yes if you have any questions in this slide or in the previous slide that the that summit spoke about please ask in the chat box okay i think there are no questions artya ask us what tailgate or lift gate is yeah i will explain you those things okay great so hood abc pillars all those things will be explained in the upcoming upcoming slides yes there is some issue with my presenting Okay, so what is upper body, what is closers and what is underbody. So this is the area which is been divided into the VIW as I told you in the previous slide it has been divided into these three areas. So what is upper body?

This shell of the body which have body side outer, A pillar inside, this is the B pillar, we have C pillar, I will show you what is C pillar, what is D pillar, everything. This is the roof of the vehicle. Okay, similarly closers hood this component enclosure.

Okay, this component in the closer call as fender. Okay, front door rear door hood. Okay, front door rear door tailgate. Okay, we have fuel trunk also.

Okay, fuel lid. Okay. So these things are closer in upper body. What we have we have hood sorry roof body side outer. It is the main styling component and this is the biggest component in automotive vehicle.

Okay. Whenever somebody will ask you what is the biggest component, the body side outer. But in this also, there is a lot of engineering. Like this segment of the car is coming into frontal crash.

Okay. This segment of the car is coming into side crash and this is coming into no crash. Okay. So sometimes what we do in vehicle, we just have a two component. joining together to make a BSO.

Why? Because in some area we need more strength and in some area we don't need more strength. So in that perspective we just break this components also sometimes.

In Honda, in Duster if you will see it has been divided into two. In Honda it is divided into three segments. Okay so this is a kind of design strategy what company used to make to understand because in automotive we have a number of regulations. and we follow NCAP, New Car Assessment Program. In that, we have country-wise regulations.

We have 10 country regulations over there, which are USA, Japan, Canada, India, China, Australia, New Zealand together, then Korean, and then European, and then Asian, consists of all this. So this is again a different topic but considering all this country regulations we used to design all our disk components. So in crash the most important aspect is underbody.

So our underbody is fully designed for the crash. Because it have all the features. It have front seat here, rear seat here.

It have engine compartment in this zone. It have fuel tank under this small zone. under this zone we have a spare wheels coming inside this if we have a third wheel third seat it will be coming here so spare wheel if there is a third seat the spare will not come in this area it will come bottom of the car we have the axle mounted in the bottom side of this area we have exhaust going through from the center of the tunnel which i will explain you in the later slides okay and then this area we have axle we have engine we have transmission ac unit everything whatever you see in the card in the in these blocks are being mounted in underbody so this is the biggest robust Zone of the vehicle what is upper body? It's the second robust zone of the vehicle and the area which is not very much strong.

It's other closer Okay, so all together when we weights all the thing it is it comes around thousand like this The entire weight of the vehicle is something 1300 kgs Okay, if I say a normal SUV car where this all combined together gives you around 400 to 500 kgs okay and then rest of the components are different okay clear okay so till now guys you are clear with the thing or you have any doubt if you have any questions please let us know in the chat box uh with respect to upper body closures or underbody okay it looks like they are clear or cement okay great great so this is how we do our uh uh this is our biw subsystem then talking about the key components in upper body So when we are talking like somebody have asked me what is A pillar, what is B pillar, what is C pillar, D pillar. So here if you can see a bigger picture of a bigger MPV vehicle. So A pillar is the pillar which we have it here. We have B pillar here, we have C pillar here and we have D pillar here.

So all together we call it a vehicle will having around D four pillars in the vehicles. can anyone say me why we need pillars in vehicle type it in the chat box uh the question is why we why do we need pillars in vehicles stability somebody said yeah support yes what else to sustain load okay very good so uh uh yes actually uh these pillars are very much required for the strength and stability at the same time we use it for having a very good stiffness toward the vehicle okay as we know for uh for these zones we need uh we have a door okay so this all are the very uh it's vacant areas okay when the loads are like uh if we consider the torsional stiffness of the vehicle how that can but is someone tell me what is torsional stiffness and carry load paths okay for carrying upper aluminum carbon steel no we are not using those kind of till now so The question is what is torsional stiffness, right? Yes. Yeah.

So, Puneet Kumar says strength to resist shear force, degree to resist torsion. Okay. So, I believe like all you have your own understanding on this and I am not saying anything is wrong in here. It is correct.

But you have to, I will just show you an example. Okay. Just we will consider a piece of paper.

if we are going to rotate it with this axis it is all easily rotatable right okay so but if we make it a frame outside the suppose just take a consider of frame picture frame if we only twist the paper inside the picture frame it can easily rotatable but if we take the frame and we will try to twist it it won't because we had provided a stiffness throughout the boundaries okay so what stiffness and okay you will say why how it is important in uh car because when we have a car okay suppose this is a car with four wheels okay when we are driving in a twisting area like it's uh it's in a you it's kind of curving so what will happen we have two forces acting on it in one in here one in here so if we won't provide this kind of pillar what will happen stronger pillars what will happen this areas will become slightly deformed okay and the vehicle will become unstable as because we we don't have a good torsional stiffness in the vehicle so to provide strength in the vehicle and to provide a very good stiffness torsional stiffness which enhances the vehicle dynamics and the vehicle performance we have to use this kind of stiffness pillars in the vehicle okay for MPV we need 4 because we have a bigger zone from C to D which is unavoidable which we can't avoid but when we have sedan from here it goes down like this in this we don't need it because the height over here is not much okay so we only use C pillar upto C pillar when we have hatchback we sometimes don't need a C pillar also we just manage this with A and B pillar okay so this is how the pillar designs takes place in the vehicle. All clear? Or anyone have any doubt in pillars? These are all the components in vehicle. So this is the A pillar, this is the B pillar component 2, this is the C pillar component 3 and D pillar we don't have it here, I can show it in here.

Okay, rear quatra panel is this panel. Okay, we have it in here and here inside quatra panel will be there inside this panel and this is the BSO, body side inner outer. Okay, and this is the part which reinforce it from the inside.

it have rear quarter panel okay seven is the roof structure this one then roof Bose is here we have it here here front middle rear and this also depends on the length of the car if the length of the car is huge okay if the roof is huge then we have to divide it more okay again the factor is same torsional stiffness and the bow the roof is not welded with the vehicle it is sometimes welded laser welded and in this area it has to be mastic with the reinforcements what we have it in here ok so we need more roof reinforcers in this part of the vehicle then we have cantrail ok this is the cantrail ok you can see it in here ok we have rear wheel house ok that is somewhere here inside because here wheel housing we call it because inside this only the wheel movement will be there and the suspension also will be mounted in here okay then we have rear drain channel which is used to drop the water whenever it's coming it's raining suppose and all the waters are coming down here all because the vehicle is moving all due to the aerodynamic all the water will be coming and it should not enter into passenger compartment so we have this rain drip channel we used inside the vehicle so it will collect all the water and it will go down from the sides it will not come inside the like passenger zone okay and then we have a combi light lamp panel so in this lamp panel other than this we have a big cutout which we call it a body exhaust a car body exhaust okay we have two kind of exhaust one is the exhaust which is coming from the engine one is inside volume volume inside the volume of cabin passenger we have one more exhaust okay can anyone say like why we need this exhaust sorry uh i think they are answering that in the chat box somebody have told dampening somebody have to remove the co2 i i'm not saying it from the exhaust i'm saying it's from the body uh volume okay ventilation like a ventilation very good which type of coating used for cars to withstand environmental condition okay Raju Yadulapalli I will answer you this question after the session when we are answering all the questions because of ventilation to remove heat to release the pressure yes then Akash Shodri who answered yes this is the answer what I am expecting to release the pressure inside okay suppose we have a closed structure closed packed chamber okay and if we have a very good ceilings and all the air will not come out and suppose when air conditioning is going on everything is going on so whenever we close the door okay as the air come inside this is so much huge it won't allow us the door to get closed okay because it it will reflect but But due to that we have this kind of small small exhaust inside the vehicle which releases this airs okay and doesn't create this huge pressure for the doors to get locked. So this is the reason and again second reason is we have to recirculate the air inside the car one is with the air conditioning we are doing another is with this kind of exhaust so that the PM model. particulate matter inside the car should not be huge okay so this is the reason why we use it so actually you are right okay so this is about upper body if anyone have any doubt related to upper body they can ask and then we will switch to closers clear material of upper body okay personal stiffness and material of what is can train okay and get what you said about second exhaust okay okay so we will answer one by one surya can you help me with the portions uh sequence okay so sorry sorry to involve you no no no okay so uh material of upper body is a very important uh aspect okay so what we have to understand is like what what kind of uh purpose this upper body solves okay so we in vehicle mostly we use steel okay so in steel we have lot of grades with we call it lesser yield grade and higher yield grade okay so lesser is something around 200 to 220 mpa and higher is around 880 mpa okay we use this kind of steels in the car but now what is important is like if roof if suppose we consider roof roof is not coming in any crash requirement okay no crash requirement comes under roof there is something coming for 2022 for that we are considering but that is again for the pillars not for the roof okay so for roof we always go for the lower yield uh steel okay but if you will see a pillar b pillar okay so these components are directly coming under go under side impact test. Okay, so inside impact test and the pole impact test this component are directly coming into play.

So we can't use 220 to 220 because the yield the crash pulse what is getting generated it's more than 220 it's around 350 to 400. So what we do in this area we try to use something around 600 MPST okay and that also there is a catch. okay the crash occurs only in this part of the vehicle okay up to this zone of the vehicle okay so what we do we we make a laser welding for b pillar okay so what we will do suppose this is b pillar of the car okay so what we do till here we will use 600 mpa okay or higher thickness higher thickness and above this we will use again 200 to 300 m okay why we use this because this is a very expensive steel okay so we if we use it throughout the component it will make it a expensive part okay so what we do we just do it uh like we just trim the part into two components second for 600 mpa uh forming is a challenge okay forming is kind of a manufacturing process to give a sheet to this form Okay, so this is again a different subject altogether. For this, what we used to do, we do hot stamping.

Okay, hot stamping is something in which we take the steel into crystallization temperature, something around 800 degree centigrade. We heat it and then we form it. So again, if we do it for a bigger component, the part getting colder is more time off.

It will take more time. okay and for this small component it will take lesser time so that is also one of the reason we go with two kind of stiffness in this area all clear so that is again how we select the steel here BSO is a part which doesn't help in the crash okay so we used again the lesser yield but Cantrell is a component inside okay Cantrell is a component which is inside this area which which is with the aerodynamic of the car we use it i think this is also one of the questions somebody's asked what is cantrel and why you use it so if i share a whiteboard yeah can you see my can like whiteboard yes yes okay okay so suppose this is the car okay uh somebody asked me what is canter okay so for that sorry sketch okay so suppose this is the car okay okay so we know our driver is sitting here right this is the position of the driver sitting in here in the seat okay suppose this is the position suppose any crash is happening from the front so this can't well before it was something like this in the previous uh if you see old car these are not much aerodynamic so nowadays the car become more aerodynamic okay just to take the load uh air in a very well manner so that the downward force will be good uh the lift force will be uh good there won't be any drag force uh lesser drag force so that the efficiency will enhance okay so then but what is the challenge in this kind of thing if you will see this this structure whenever the crash will happen the driver head is well safe from the top from the here and from here okay it's none nowhere near to the these kind of pillars but now what happened when we had this aerodynamical consideration what we did we bought this pillar near to the driver's head zone okay so now this pillar have to be very much strength there because if the crash should happen it should not come in here so what we do in this area we make a program deformation suppose a deformation is happening whenever the crash is occurring and the deformation is coming in here we make our crash in such a way the deformation will always happen in this direction means this will break in this manner not in this manner. Okay, that's why we call it here a program deformation.

So we give a crack and whatever load will come the crack will always come in this area. Okay, so can trail why we use can trail to this is a one ribbon which takes vehicle from front to the end and why is it in this shape now because to consider as we are considering aerodynamic structure, so this has to be here. okay in here and the glasses will be also coming and resting on the canter I hope your doubt for canter is done so there is one more question someone have asked me that is regarding okay a build up a body with 3d printer will it have more strength but what material you are using again it's a very expensive and time-taking process one thought process is since there will be questions to the topic that you also teach what we can do is for those kind of questions we can keep it at the end so that your flow kind of uh goes fine okay sure because i i want uh them to get cleared in every area like yeah absolutely absolutely so for the for the questions that they have about these topics that you teach yeah that i am answering uh if they are questioning something apart from the topic guys uh please make it sure like we will be doing in the end of the session so that i can answer you in uh very well manner okay so right now if i'm asking you some question try to answer in that way in that zone only okay so i hope uh upper body question uh thing is clear with you then we have under body uh sorry closers as i have told you the components which are getting closed are closer but we have a separate part which is fender why fender is not inside upper body and under body because it is a part which is not been welded into the car it is always been bolted into the car okay so underbody zone all together it comes as a weld component upper body comes as a weld component then they will fit all this component inside the car that's why we call all these closers okay same applies for fender but it doesn't open and closes it always gets closed it never get opens if we want to open then that is a different criteria so this is the component hood bonnet assembly we call this hood second is lateral door and front door that is the this one the frontal door this is the rear door uh fourth one is the trunk uh fuel door or trunk lead we call it okay sorry fuel lead we call it trunk we call for doors uh tailgate okay and then fender is the fifth one the balloon got missed okay so this is uh this is about fender Somebody have asked me, I have just seen in the questionnaire, somebody is asking what is FMVSS for hood. Okay, so first you have to understand what is FMVSS.

It's a United States law for the crash. Okay, for hood, yes, we have pedestrian head impact, but it have different consideration. US is the only country which don't have a head impact initially, but now they have to integrate it.

Okay. So that is something different. OK, so these are the components.

Whenever we design our doors, we have to take a lot of things into consideration because we always open and closes the door. OK, so we whenever we design and when we test, so we close the door like a lakh times. One lakh eight thousand is the cycle time for a door to open and close. OK, similarly, it is for the rear door. This is not for one lakh.

It is for some sixty four thousand. and 48000 times this is how the testing for the doors have been done so in this testing what we see the doors should not get uh bended it not that deteriorated it should not bend it should not deteriorate and it should not break anywhere okay with this one lakh eight thousand cycles so this is what kind of test we do for the doors the similar kind of test we do for hood but the numbers are not huge uh like one lakh It is around 30,000 or 40,000 for some of the regulations. okay because we open doors more frequently than the hood okay in this also we have primary lock secondary lock okay so uh anyone know what is secondary lock and why we use it no uh this is not related to child lock suppose you are driving if we we have a secondary lock if whoever driving a car they might be knowing like when we open a bonnet it won't open full okay it will just the primary lock will be unengaged and the secondary rock is always a manual lock it's it should not be a automatic or it's a motored one why because suppose you are driving in a speed of 120 kmph okay suppose you are driving your car in a high speed okay and all the aerodynamic effect is happening in here and suddenly by mistake you triggered your hand on this latch area for the hood So this will all due to the air effect it will open like this.

Okay. So it will open. So what will happen you will have a like your visionary will be getting affected and you may crash in your vehicle somewhere.

So all due to this reason we always have a secondary lock in here which is only accessible by the hands. Okay. So suppose you are driving in a high speed and you are by accident your hood. the primary lock get disengaged this will not open it will still be intact okay but you will feel some vibrations in this area which will alarm you that okay this area is nowadays we have a digital cluster it shows okay your bonnet primary lock is open okay so that you can open okay that is the only reason why we have still a manual locking in this area not a electronic locking for any kind of car okay that is what why we use uh hood uh like uh in that purpose second is like all the closer components uh the components are not a very uh like they are not into lot of uh crash regulations okay we have some regulation related to pedestrian impact but not related to high crash like kind of we call like uh the load absorbing and all but that is for hood tender also doesn't absorb any load hood also doesn't absorb any load but with hood what we have we again as i explained you about the can trail okay how the deformation happens in hood also what we do we give a program deformation so that whenever the impact will happen the program deformation will be like this okay so that this complete hood assembly should not bend and go into this passenger zone okay suppose this is okay suppose this is my car okay this is my car and this is my hood okay so if suppose the crash will happen and and with any pulse if this goes back in here and we hit the windshield and all or go inside but what we do as a designer we give a compulse zone in here so that whenever the crash happen and this engage it will not break everything on the vehicle of the hood.

Okay, this areas and all. So what it will do it will break in this area as we planned that deformation as a designer. Okay, so hood will absorb whatever energy it will have it will be there.

It will absorb and it will break in here so that the load will not be transferred from here to any other part of the hood. Okay, so that it won't go back and hit anywhere of the zone and it won't absorb the load then all the load will be absorbed by the underbody okay so that is the second area where you will see a program deformation in the vehicle okay who in doors we have for frontal crash because as we know the load is traveling from here front okay i will color it from the different color okay yellow you Suppose the load is coming like this and from here it has to transfer in all part of the vehicle. Okay, we have B pillar here.

Okay, we have A pillar here. We have canter here and we have the bottom seal here. Okay, so when the load is coming the first point of contact is from this area the side member and this side member from the center it takes it till the rear of the car but from here from the side end of the car it transfer it from here top from here it goes down and from a pillar to b pillar we have one skirt We call it skirt or stiffener rod in the door. Okay inside somewhere here.

Okay, what it do do it like it takes all the energy and transfer it to B pillar and from B pillar. We have the same kind of rod in here which transfer it from B pillar to C pillar. So that is how the load is been transferred from front to the end of the cart with the help of this kind of designs.

Okay. Similarly, we will be having one more rod we call is G bar or anti-intrusion beam. So it is also like this in here so that whenever the impact is coming from the front, all the load will be going in front A pillar and the B pillar of the car, not inside the passenger area. So that is how this door panels comes into play.

Rear gate, tailgate is important. Now we have lot of crash regulations coming for rear also. China and USA have a rear crash with 80 kmph speed.

Okay. So in that area also the criteria are this should not break and go inside. Okay.

So that the designs are very much robust in this areas. Okay. So this is all about the closer assembly. If anyone have any doubt related to closer can ask me now.

Only related to closer. somebody is asking which type of sensors used for to know close and open of the door it's a touch sensor and the impact sensors we have it okay and that is on and off sensor it's not a huge sensor and it's a very less cost sensors okay no doubt what is fender i have already explained you what is fender this component we call it fender so you want to know more about fender okay So the fender, okay, see why the fender is bolted because in underbody, okay, if you can see, okay, so this is the skeleton of the bottom skeleton of the body, okay, this will come and then upper body will come and then fender is been mounted half in here and half in underbody. It is bolted in here as well and in upper body as well. So we can't.

bring that fender with any of this component. Okay, so that's the reason we can't weld it with some area so that we have to weld it in again different area. So we put this fender always as a bolted object.

And the second thing is whenever the crash happens folder this fender gets deformed very easily. If it will be welded, it is very expensive. It's an expensive process to like repair it. but if it is bolted you can easily unbolt it and you can repair it.

Okay and third thing is it is not a load carrying object. Okay, only purpose of this fender is for styling and for the wheel aperture like wheel should come in and come out that is the only thing we need it for fender. Okay, so we don't need it to be very constraint lot of constraint manner we don't need it so we don't need any welding and all in here it's just a one component we even don't have fender reinforcement for wood we have a hood reinforcer inside uh for door also we have a door reinforcement inside tailgate also we have an enforcer but for fender we don't have an import even for trunks also we need we have an all because this we don't need any statical stiffness stiffness of this component we don't need any internal stiffener or internal components in this area. Okay, so I guess it is clear what could be the generic design tolerance limit for these parts. So tolerance of these parts are again for the surface tolerance we always use monon more than 0.5 mm.

Okay, for the edge tolerance it should not be more than 0.1 mm. Okay. for the holes and all it is we have a general tolerance for all the kind of hole standards okay only for surface and the lines i have already told you what is the tolerance level we maintain okay which previous picture we don't have rear side fender in car okay so fuel door it's a it's a component like we we we have this filter with a inner reinforcement and the hinge assembly we always have a positive locking in here which locks and unlocks with the sensor so the fuel the gap and flush at the fuel lead is very much important because if the gap in flush is not been maintained it is virtually it can be visible with any of the customer or any defects in this area or any different sizing or different flushing in this area so this area is very much critical second important aspect in fuel door is like it should always flush with the outer panel so that the aerodynamical drag should not affect this zone. So that is the reason this is a very important aspect of the car. The water should not get stick here because we have unprotected zone inside which get rusted if it is not well designed.

So this is how. So what is gap and flush I can explain you those area. Suppose this is door.

Okay, it's a BSO. and this is a fuel trunk. So we always maintain a negative flush.

What is negative flush of 0.5 mm means this body side outer component will be in higher side and this one is always in the negative side. So that whenever the water comes from here it should not enter in here. From here it goes and here it comes out.

So it is sometime also tilted in this manner. This one. Okay, so how it is been from here minus 0.5 and here it is plus 0.5. Okay, sorry 0.5 so that whatever the water comes from here comes here and goes here.

Okay, so this is sometimes we always maintain 00 type of plus but that is not possible. So we always keep a tolerance of mine 0 to minus 0.5 0.5. okay not more than that that is the tolerance limit we maintain in this kind of zones so uh this is all about closures so we will move to our next area that is underbody okay uh anyone if anyone have any doubt they can ask me or we'll move to the next area we have any question mr clear thank you i will answer these kinds of questions later after the training has been done okay uh forces act on closures okay what is the aerodynamic forces acts on the closer while moving when the component is moving when we have a when we are closing the component we have a force the like closing force and opening for closing efforts okay when we drop our like food from when we unlock it and drop those are the forces acting on closers those kind and the in static condition these are the forces and when in dynamic condition aerodynamic is the only thing and sometimes if it rains and those are the forces which is acting on closures defining fender you showed one diagram okay okay we have been talking about underbody so this is the main area of vehicle which is not related to the styling of the vehicle which is related to the performance of the week okay Why because all the crash loads have to be absorbed from in underbody.

Okay, and all the things like the vehicle the seat mounting also is in the underbody. Okay, so related to any safety all the even the steering wheels everything is been mounted in underbody part of the car and it is the only component. It is the only area which have more number of component than any of the other areas.

Okay. it have somewhere around 120 to 140 components where in others it have 60 to 70 component in like upper body and 40 to 50 component in closer okay but in underbody we have 120 to 140 components okay so there are huge components and a huge parts also which is being used in underbody so i have just shown like for what all are the 15 areas we have shotgun which is here which comes from a pillar okay which takes the load uh for uh which takes the load to the side of the vehicles okay the uh bot uh like uh this area the front uh this area uh front wheelhouse and the bottom traverse member this takes the load to the bottom part of the vehicle and shotgun takes the load to the sides of the vehicle okay second is front wheel housing okay this is the front wheel housing below this we have our wheels okay third is a suspension tower okay shock tower we call it in automotive also so that all the load will be this is a very uh robust area because lot of loads of the suspension will be coming on this area code is dash and firewall that is this area which you can see so dash is the one of the biggest component in uh underbody because it have lot of mounting it have mounting for your CCB is like cross carbine where all your dashboard your steering column everything will be bolted steering is been bolted to A pillar to A pillar and then inside in the dashboard all your like brake booster pedals everything will be it is mounted in like CCB and the passing is been gone through dash panel okay steering passing is also going through dash panel it is also a heat chamber uh heat shield because it won't allow the heat coming from engine to the compartment zone okay it also have our refrigeration unit coming into from here and mounted in here okay so that is all about dash panel call it up panel is uh here uh where we used to uh like uh the call it off panel is here yes because it is also the water box area and call it up we call it because the like the windshield has been placed in this area okay and even the whatever whatever water is coming from the windshield is getting collected in here and going out of the vehicle okay so this is all about uh uh call top this is how the water flows out of the vehicle we have a hole over here so that the water will be coming out from the bottom outside of the car. Okay.

So six part is the floor assembly floor assembly doesn't have any loads. So we put it in a very lesser thickness of 0.6 mm. It always only carry the load of leg and other things.

Otherwise all the load will be taken by this member cross member where the seat is being welded. Okay. So this is a stiff area. This one is a stiff area and this side is a stiff area. and in between where we using our sheet panel those are not a very much higher stiffener stiff tail okay so this is about floor assembly central floor center floor is also here uh rear floor is somewhere here okay this one okay here we used to put our uh okay first i will clear okay this is the central floor zone okay this one this is the rear floor zone okay So this even protect the fuel tank from the top.

Okay. And this one have spare wheel inside the vehicle. Okay. So we have both kind of provision inside the car.

So that whenever the fuel should not come inside the cabin compartment zone. And this wheel. And for this wheel there are two types of provisions. Sometimes it comes inside the car. And sometimes it come bottom part of the car.

Okay. that depends if we have suppose you will take examples of duster and all we don't have it in here we have it in the bottom part of the area but if you will take any sedan car we have it inside in here in hatchback cars also we have it in some time we have it for SUVs also okay so that is again a strategy for a companies like how they want to provide and where they want to provide the spare wheels okay so floor cross members are this kind of members where our sheet is getting bolted so seat is getting bolted in here here that is for the left seat okay here and here that is for the right seat and here from this zone to this zone this is for the rear seat bench okay this is how the seat is been mounted we have a time constraint so i can't show you exactly where and where so i'll show you later okay floor tunnel why we have a floor tunnel so that the 4x4 rod and 4x2 drive shaft can pass it from here at the same time for 4x2 the exhaust in 4x4 drives out as well as the exhaust line should pass from here and 4x2 like two wheel drive this will pass only the exhaust line okay so that is why we have this tunnel over here okay Then we have a kicker panel here because why we call it a kicker panel because below this after this we have a fuel tank or the battery in the new generation car. We put it in here and the leg should not go below this behind this zone. OK, that's why we keep it as we say is a kick off panel. OK, so that the leg of the rear passenger should not go below this line.

okay so that is about this zone then we have sill panel that are the two stronger line of stiffener going from the side component of the car like this one and that side also it travels from here to up to the end of the car okay cab ring panel is again the same one here what i have explained you rear apron is one where the tailgate comes and get fitted okay so if we have that apron so where the lock of the tail there is been getting engaged okay and then front or rear seat support member so for seat we used to have the support members so for that we we have one extra brackets in those areas okay so that is all about components in biw so till now if you have any doubts we i'll I am happy to clear you and then we will go to the different zone. Okay. That is how the assembly process has been done and how the other.

So till now if you have any question you can ask. Yes. Powertrain comes under underbody. Do design changes according to material. Yes.

It does change. Explain on tailgate and that is already considered explained. Okay.

Okay. Great. Yes.

It's a huge area. BIW so yes okay somebody asked me about shotgun okay define a and rear uproar okay so what is shotgun suppose if I will okay you can see my whiteboard can somebody answer so suppose this is the structure of the car okay so this is two cross members of the car okay which is going till the rear end of the vehicle vehicle. Okay. So this is the center part of the vehicle.

Okay. Suppose I am explaining in that way. Okay. So this is about the center load.

So this is the first part which takes all the load from the impact from the front. Okay. It even have the engine mounted in these two blocks also only. So what the underbody is fully designed as per the for the crash. but upper body is not been designed more into crash so but it should also absorb the energy so what we have done we have used a second member okay which will also absorb the crash when this fills up to this area okay then only this member will start absorbing okay so when the second absorbing area we call it shotgun okay So, if I'll explain in here, so you can see this golden part from where it's starting.

Okay. So, this is from here, the second load impact will be absorbed. That will be absorbed to upper body.

Okay. Center area and the side of the car. But this one, these golden areas.

this one this will absorb the first load of the impact okay and will transfer to this till this areas in the center way this goes from bottom till here okay so this shotgun is here is to deliver the force from here to the top of the car to the bottom of the car and to the center of the car that is why we use this shotgun okay second is apron what is apron is like we it is a rear filler in this area suppose here we don't have any apron but in here we have an apron okay what will happen you you whenever you will open your tailgate you will see one panel okay in which there is a gap where the latch is there okay which will get an hooked which will get hooked with the tailgate okay so that latch should get locked okay with this area so for that purpose we use the rear apron okay i hope it is clear clear the one who have asked about shotgun and uh fender oh sorry apron okay clear so kick kick panel okay so you guys are making me revise all this area okay okay kick panel is the one okay suppose here if i take a section in this area so this is the our base plate of the card and this is the kick panel i will explain in here okay so suppose this is the base okay and this is the kick panel and this is how it goes in the vent our seat has been placed something like this okay and the leg is coming here in this way okay so this is how the leg leg is been placed okay so if person leg is going below this zone somewhere suppose the kick panel is not messing with it and it will be here so what will happen the person leg can truck and he can fall coming out of the vehicle so for that reason what we do we just have a kick panel in here so that the person leg will not go behind this line okay this is the brief explanation of kick panel so that the whenever it will kick it won't go behind this it's a human physics we have to understand okay so this is a person should not fall when he is coming out of the car you this doesn't happen for the front passenger because in front passenger we have lot of space okay for the rear passenger we have some space constraint okay for that reason we used to provide this kind of provision okay that's the reason we call it kick panel uh somebody have asked me about dash area right so dash is something like this is the dash okay all the ac uh suppose these are the other rod okay this is the steering going inside the dash this is So all the heat panel no heat should come inside this even whatever the load or pointing things it should not make this dash deform in such a way that it will damage the passenger. So dash is that's why it's a very important aspect and it is very well reinforced in all the area so that the dash intrusion is the car will be minimal okay it should not be high. it should be always minimal okay that is about all this area so that's it about component of the cars okay i don't have any in the individual pictures right now okay so now is we have to understand how is the assembly process inside a company okay like how it is been done so uh one is uh one as area is our body assembly which i will explain you how it has been done but before body assembly all our component is been made out of sheet metal ok so this is the sequence how a car is been made inside the factory first a sheet metal will be coming ok and it will be getting stamped inside the press shop ok then that components have been gone is going to body assembly shop where we use to weld it all together so to make an assembly okay then this will call as a body in white components then it will go to paint department okay where it will get painted then trims and chassis area will be coming okay where all the plastic trims will be fitted into the vehicle plastic trims seat and all things are been fitted into the vehicles okay then TNC chassis where the the bottom chassis parts the axles and all parts have been bolted together joined together and it is also being tested in this zone how the suspension testing the rolling testing those kind of tests not for all the vehicle for all the vehicle we will be having that test and we have separate in one stock will take out some of the vehicle and we have a rig test also okay we have a small test rig where we will test the vehicle the first go then we have an inspection area well we inspect with a lot of quality inspectors which will see all the smaller smaller defects if there is any paint defect so or any dent on any other panel the car will get rejected it will not be getting sim okay so it should clear all this zone to get sim okay so this is how the car has been made first stamping then the body assembly where all the components will be bolted and welded then paint After the paint, all the supplied parts like glass, the windows, fitments and all, the seats, the plastic component, mats, roof mats.

everything will be fitted okay then tnc where the chassis uh the engine parts are being fitted then the inspection and then the car is gone for shipping okay this is the sequence for uh the car to be manufactured but in the varied shop how it is been divided as i have already told you the component of the car is been divided into three areas one is underbody second is closer and third is upper body Okay, so in underbody we have three areas as I told you front area engine compartment area if you remember I have explained in you in here engine room cabin floor and the rear floor okay. So this is how the assembly looks okay. So this is the engine area.

So this is the complete assembly and these are the sub assembly which will get welded together to make this. This is the cabin area for the front. this is how it is all together and welded to make this then this is the rear floor how it has been welded a skeleton and the surface all together so this all together one two three combine to make a complete underbody okay then we have body side okay that is with body side outer body side inner panel then quadracore panel all together when we assemble we make a body side outer assembly for the side and for the right side is different roof altogether will make an assembly okay and then the tail altogether will make one assembly okay so all wind will fit it is coming up to this skeleton zone okay till this skeleton zone first is front unit this is the example of renault logi in which I have worked this is how the front unit will come then the front and middle then the rear floor then with the side panel want I can sorry zoom this area then the sides how it is been used this this area is been welded in here and this reinforcement will is been welded okay all together then the roof is been bolted or welded whatever it is okay and then all the closures coming so in hood also we have small small component hood outer hood inner and the reinforcements for the latch and the hinges okay for door if you will see front door we have anti-inclusion beam skirts front beam outer panel sash type panel inner panel all together we make a body door outer okay similarly we do the trunk lead with the outer panel and the inner panel reinforcer with all the hinge reinforcement and the latch enforcement so all together when we complete our biw from here it goes up to here the assembly occurs in this progress so any doubt in this two assembly sequence anyone now i will explain you about the welding process in upcoming slides maybe tomorrow not today yes i will explain you about hemming also anyone have any question related to these two assembly uh area clear all clear okay great great so chassis fitted in tnc uh chassis okay chassis you mean the engine and complete engine suspension axle all together will be fitted in TNC yes first one is engine fuel tank comes in this zone ok in the rear floor as I have explained in the this zone of the vehicle is where the fuel tank is been bolted ok here under the front of this area ok I can explain in here also in this zone okay this outlet which you see a small hole in here that is for the fuel pump okay so that you can like service your full pump if there is any issue no biw contains all the sheet metal parts before painting this this is all biw components till here okay and this has been uh like painted and then sometimes it is getting dismantled all the doors will be getting dismantled and they have to fit a lot of things inside the door so after the paint they dismantle it and then t t and c they will assemble it again okay software we use a lot of software nx uh like depends on company what what company is using some company use next some company use scatia some company use solidworks uh so it depends on company so this is all about all about assembly process so I will show you some of the videos related to part and manufacturing and assembly process and then rest of the things we will be discussing on tomorrow maybe okay you can see my screen guys can someone confirm okay you can see the video running youtube okay great so uh so if you can see this is a complete car as i have explained you these are all the classes surfaces uh in the area which is been given by our styling team to us from which we extract the complete car okay roof panel body side panel fender panel hood panel hood inner panel and the other areas okay tailgate tailgate panel front door panel okay front door inner panel is also there okay can you hear any music no right i can't i can't hear it hello i i think i don't have access to music i i can't play the music how can i help i i don't know but uh when i'm playing before it have a sound but now i can't get the sound i don't think you can share a sound from your screen on you might not share oh okay okay yes yes share sound option is there yeah thank you thank you Now people can you hear it?

Okay. There's no sound. You can only see the video.

Okay, leave it then. I think there are some audio issue I have to deal with my mics and all. Okay, there is no such informatics sound in here.

It's just a music to entertain you guys. Okay. Again, so these are the areas like as I have explained you, so you can go through with this video also, which will say this is again where the spare will be there.

These are the shock tower, front side rails, which absorb all the load and transfer it to back outside of the vehicle. Tunnel, which takes the load from the end at the same time. It has an envelope for our exhaust passing and the drive shaft passing.

So this is all the components, it's a rear shock tower, rear sheet panel, okay, heel board or the kick off wall what we have explained. Dash crossmember is for the dash reinforcement, okay. Rear back panel is for the sedan cars most of the time we have it, we don't have it for our hatchback and this one. Okay, so this rear back panel we have it for apron also, okay.

and in the sedan car if you behind the seat we have one panel area also that is also be said as rear back panel okay so this is all about the components you can see inside the car okay this is upper body okay B pillar B pillar inner B pillar is again I have as I have explained you it has been also used we cut the part and we use in for two variants D pillar how it has been used C pillar outer side sill that is for the side crash things and all okay closers these are the complete inside enforcement this is a window frame at the same time sash frame also door waste beam is used to send the energy from here to at the back also okay anti-intrusion it's for the side crash we use this part okay crash management system this rear bumper and front bumper have been used for some heavy related crash okay or pedestrian bumper some country have some strict regulation suppose europe and us have a rcar related concerns so for rcar if the car is hitting with the speed of 10 kmph none of the area should be affected unless only this part should get affected okay for that we use this bumpers in the front and the rear these are the steel bumpers which comes be after the plastic bumper and the absorbers inside the car this is the cross car beam which holds everything like the steering the pedals ac air conditioning areas everything of the car is been like in the dashboard everything whatever you see is been assembled in this crosscar beam okay But that is not a battery boxes is in this underbody central area below the car unit below the underbody unit the sheet unit. Okay, so we used to produce this is how the painting process is been done. Okay, this is all about the parts. Okay, the manufacturing process is this. This is how the stamping is happening inside the car for the part components okay so this is the tool uh punch and die which we use in the industry okay to make our component inside this we'll put a small small sheets and we'll get our form component they have loaded the sheet metal inside this sheet and this die ok so this is the die how it is been working how the load is been acting on the component i was telling you guys about the piyosa so you can see how the piyosa looks Okay, first strike of the car of the BSO.

So in BSO we generally have two strikes. One first strike, one the second strike and then we have piercing operation then we have trimming operation. after first forming so this is all related to the manufacturing how it has been done in automotive and this is the assembly process video. Good grammar and spelling are important, but if you want to write essays that inspire, messages that forge brighter connections, and email.

Car doors have come a long way over the last century. So you guys can see this car door video, how the manufacturing has been done. I'll mute the video.

Okay, I will mute the video. Okay. so guys can you see my video of the car door how it's made cardo okay great okay so you can see this uh i have just kept one ppt uh one video for this how it has been made okay the car door so uh it's from the rolled sheet it is it is it has been cut and as a component and see how it has been kept inside the tool and this is how it will be formed okay so this is the first draw it has been made okay you can see okay now two two lh and rh has been divided into and it's been cut uh they have separated it with the trim operation and now they have all the forming uh piercing operation they will be performing in this okay so we have now both doors LH and RH doors so the quality inspector is inspecting all the roughness and all they will say so this is how they will do this is the window frame the top frame this is the front reinforcement where the hinge in all will be fitted this is the rear inner panel of the door assembly okay and this is how they are building it this is a spot robotic welding process we had we even have a like manual process of welding also this is an anti-intuition beam and this is the upper vest okay that is used to transfer the load from front to the end of the car okay and then they will put this again it's a robotic welding this is how the uh arc this spot welding they are doing for the components okay this is the mastic provision adhesive provision how they are providing okay for hemming operation now the outer panel of the door and the inner panel of the door it is not been getting welded it is been attached together adhesive why it is not getting welded because after the weld it always leaves a mark okay which is not acceptable by customer by visible they should not see any welding marks on this kind of a surfaces so that that's the only reason we used to do adhesive we used to provide adhesive okay in this areas because and even though adhesive is an expensive process but all because it have a visionary impact in the car and the customer directly can see it okay we use to provide this kind of adhesives in the car okay okay so you can see this is how the assembly for all the biw component is is been done in the door door panel and this is how the TNC in TNC of doors how everything is been fitted okay so this is how the handlebar is been fitted this is the chrome fittings at the top this is how the windows are be fitted okay so you will see on the inner plastic IP and all other things glasses how it is all been fitted together you can see it in this video This is the rail for the windows to move.

This will be moving in this way only. This is a side mirror. Side mirror sometimes be fitted in the body.

This is the complete IP mixed with soft and hard plastic. Again it's a different area and how they are testing the functionality of the windows and all and this is how the door SMB has been completed. okay and door assembly is also getting fitted in TNC of the car okay after the paint the door assembly comes out of the car and after this all the seat and all the dashboards everything is been fitted they assemble this doors in the car clear this is how they do hood and this is their what they are checking is the gap and flush so the gap and flush should be all equal okay they are checking this uh it should not have any impact okay so this is the complete tour of uh how it has been made okay so uh uh one last video i will be playing for today is like animation of body and white assembly how it is being done Okay, you can see my screen. Okay, yes. Okay, so this is how all the component is being assembled.

Okay, this is only the rear area. This is the front area. This member is only the member which is transferring all the loads. It's for the sedan car.

Looks like a sedan car. Yes, because they have a separate member in here. Okay, that is only been used in the sedan car.

this is all the components which have been used in biw bso roof members and all some bottom tray kind of things where we use to keep our spare components and all so this is a very expensive unit of the car expensive car okay it's something like bentley alpine so they are using for different different kind of uh more members it's a Aston Martin sorry so they are using different different members inside the car okay which is not been used like some here okay this is not this enhances more torsional stiffness because the vehicle have more dynamics and the higher speed okay so it should not get deteriorated that's why they have more stiffener agent in this area sometimes they use different materials in these zones they use more yield component like sometimes they use magnesium sometimes they use aluminium with alloyed casted aluminium also okay so all together they used to make this kind of zones so that's it for today

Transcript for:Lecture Notes on BIW Fundamentals

Transcript for:
Lecture Notes on BIW Fundamentals