[Music] [Music] [Applause] so [Music] [Applause] [Music] welcome you all on this nptel online certification course on mechatronics today we are going to discuss various examples of mechatronic systems ah in last lecture ah i have talked ah a lot about the introduction part of it i introduced ah the course to you and today we are going to see various mechatronic system examples so ah initial two examples i have taken from our ah daily life equipments and the next two examples are from ah small robotic kit ah with the help of which i will be ah trying to explain you ah what are the various mechatronics component of ah in it so the first one ah is a four stroke engine ah where we will be seeing ah how the mechatronics helped us in ah making a proper ignition timing and of air fuel ratio mixture ah to be sent to the engine similarly in the second example ah in a copy machine we will be seeing what are the various steps and in copying and how mechatronics helps us in doing all those steps and as i said ah next two examples lego nxt is a mobile robot kit basically supplied by lego and similarly ah toddler simple small walking robot is again a kit with the help of which we can simply understand the various mechatronics components so coming to the first example that is the four stroke ah engine let us look at what are the various four stroke sequences ok so these four stroke sequences are intake stroke compression stroke power stroke and exhaust stroke so ah let us have a look at it ah here in this figure we can see ah the various four strokes are mentioned intake stroke compression stroke power stroke and the exhaust stroke so ah we can see on this figure the various component we have piston and we have cam shaft okay and here you can see that ah there is a spark plug for ignition and there are two walls ah one is the ah intake valve and another is the exhaust wall so in intake stroke as you can see that this intake valve is open and we get the mixture air fuel mixture ah into it like this okay and after that ah your piston keeps on moving downwards okay so that completes uh the intake stroke when it reaches to the bottom most position and then takes the compression stroke and in compression stroke what happens we have ah the intake wall gets closed and naturally your exhaust valve is already closed so you can see the closed position for the intake valve and exhaust wall and then with the motion of the piston ah air fuel mixture ah gets compressed basically that is why this is called the compression stroke okay so we have the mixture being getting compressed next is the power stroke now in power stroke what happens there is a ignition which is given by the spark plug so spark plugs gives the ignition here this is the spark plug and again in this position both the walls are closed and after ignition ah the air fuel ratio that is there is the burning of the fuel here and those gases burnt gases they expand basically ok so hot gases expands and because of that we have a motion of the piston and our cam shaft then rotates so this is how we get the power stroke and in exhaust stroke ah what we can see that the exhaust wall gets opened as you can see in this figure and your exhaust gas come out from over ah here and in this case ah our index valve is ah remains closed so these are the four steps that is the intake stroke compression stroke power stroke and exhaust stroke and with the help of mechatronics what is done is that we try to ah control ah spark timing we try to control air fuel mixture and we try to control the fuel injection okay so ah we have a actually ah microprocessor ah as you can see in the this block diagram there are various input parameters over here for example we have engine speed crankshaft position spark timing ah feedback then engine temperature is there throttle position is there and mass of ah mass air flow is there okay now the output of the microprocessor system is the spark timing air fuel mixture and of course this controls your solenoid here that is mixture control through solenoid and there is a fuel injection wall so ah the power and speed of engine are controlled by varying the ignition timing and the air fuel mixture ok so what happens actually for spark timing what is done is that crankshaft ah drives a distributor and distributor makes electrical contact for each spark plug and a timing wheel now timing will generates pulses to indicate the crankshaft position and then the microprocessor adjusts the timing ah which high voltage pulses are sent and to the distributor so they occur at the right moment time so this is how ah spark timing is controlled with the help of microprocessor similarly for air fuel ratio control what is the done is that microprocessor there is the time for which a solenoid is activated to open the intake wall on the basis of input received ah about the engine temperature and the throttle position so with engine temperature and throttle position as the input microprocessor controls the opening of the ah the solenoid valve okay so this is ah how it is done then similarly we have the fuel injection control here the amount of fuel to be injected into the air stream that is determined by an input ah from a sensor of the mass flow rate ah of air flow or it may be ah computed with ah from various other ah measurement so this is how uh mechatronics uh help us uh in the igni uh igni speed and the power control of the ah engine okay so ah next example is another a very popular example of the copying machine okay ah the copying machine ah has got both analog as well as digital circuits ah there are many sensors in it there are actuators and there are microprocessors so essentially we have all the components of a mechatronic system in a copy machine ah if we look at the working of the ah copy machine ah here are the various steps first of all what one does is that is the user places and ah original which is to be copied in a loading bin and pushes button to start the process okay now what happens next is that the original is transported to a platinum glass and a high intensity light source scans the original and transfers the corresponding image ah as a charge distributor ah to a charge distribution to a drum now ah the blank piece of paper is it retrieved from a loading cartridge and then the image is transferred into that blank paper with an electrostatic deposition of ink toner power powder that is heated to bond to the paper ok and then finally a sorting mechanism delivers the copy to an appropriate bin so these are the steps ah in a copying machine now here ah if we look at it ah how the control ah takes place basically in this mechatronic system so the analog circuit controls the lamp the heater and other power circuits and the digital circuit controls the digital display indicator lights ah buttons switches from the user interface other digital circuit includes logic circuit and microprocessor that coordinate all the functions of the machine now what are the sensors in this there are optical sensors and micro switches ah to detect the presence or absence of paper whether paper is present or not ok ah its proper positioning so that you get the proper copy of it and whether or not door and latches are in proper position so for this optical sensors are used and the encoders are used to track motor rotation so these are the sensors which are used in this mechatronic system coming to the actuators there are servo motors and stepper motors which are used to load and transport the paper turn the drum and index the drum okay so these are the that is the three operations for which the actuators are used and we may have servos as well as the stepper motor for this purpose next example ah which i want to ah talk about is the lego ah nxt so it is a basically simple kit ah which these days many in many laps basically these kits are used just to demonstrate ah what various mechatronics components here are ok so this robotic kit is from lego so here again we will be seeing the various actuators sensors and the ah control controller so ah coming to what are the lego ah sensors available in this so ah there is a touch sensor ah there is a sound sensor there is a light sensor and the ultra ultrasonic sensor is there okay so the touch sensor basically enables the robot to re respond to obstacles in the environment sound sensor enables the robot to respond to various sound levels similarly the light sensor enables the robot to respond the variation in light level as well as color and ultrasonic sensor ah enables the robot to measure distance to an object and to respond to the movement okay so these are the various ah sensors which you can see the touch sensor sound sensor okay light sensor and you have the ultrasonic sensor coming to the actuators so servo motors are there so here with the kit the three servo motors are provided and these servo motors ah can be ah connected through ah the controller over here okay ah so these servo motor ensures that the robot moves ah smoothly and precisely so we have actuator we have sensors and we have the lego controller which is a nxt brick so this part is basically the controller part or what we call it as the nxt break this is an intelligent con computer control lego brick the nxt ah what we can say is that the brain of the lego mindstorm educational kit so these days these kits are available at very reasonable cost and one can very easily program these kits and one can generate the various type of robots for example you can make a walking robot ah you can make some legged robot ah you can make a mobile robot out of all these kits and you can do the programming either directly through the brick or you can do the programming through the ah software ah which is provided along with the kit through your computer next example is the toddler walking robot ah which i want to talk to you ah it is a basically a two legged ah robot ok and again there are various mechatronics components in it there are sensors there are actuators and ah there there is a ah microcontroller as you can see here okay and there are sensors so ah actuators here are ah servo motors which are being used and the sensors which are attached with this kit are ir sensor for obstruction detection ah that is infrared sensor then we have the bumper sensor for uh obstruction detection ah basically these bumper sensors are nothing but the just like switches basically so ah they make uh on and off contact okay then we have compass for orientation detection we have accelerometer accelerometer for tilt detection and ultrasonic sensor for range detection okay so we have actuators we have sensors and these actuator sensors are ah connected through the microcontroller which is here the basic stem to module okay so this way ah is this toddler walking robot forms a complete mechatronic system similarly we can look at stepper motor position and speed control okay now if we look at this figure here we see we have as a stepper motor here there is a stepper motor driver and this driver is connected through a pick pic microcontroller and then we have modes for input that is a potentiometer ah then we have one analog to digital converter is there there are more switches and ah there are position switches and you have the light emitting diode here just to see the working of it okay so the actuator here is the stepper motor then sensors are here ah we have switches are there ah then potentiometer is there okay and the microcontroller is the pic microcontroller okay so the stepper motor position and speed control this also we can ah take it as an example of the mechatronic system where we have sensor actuators as well as the microcontroller next ah another example i wanted to tell you ah where ah the dc motor is being used as an actuator okay so here the dc motor position and speed controller ah that is through hbs driver and pulse width modulation speed control that is pwm control so here we can say there is a dc motor with digital position encoder these encoders are the sensors ah i will be talking about much more about how the encoders work what are various type of encoder in the section when i will be talking about the sensors okay so ah there is a hb driver here and the encoder signals are sent to the quadrature decoder and counter and then these signals are sent to the slave pic we have a master pic so these master and slave pic are nothing but they are the microcontroller and then for input we have keypad is there switches are there and whether our keypad action is going taking or not that can be seen that can be identified with the help of buzzer and we have a lcd ah display so here we have the actuator as the dc motor then we have the sensors that is the encoder and switches and the microcontroller is the pic okay so pic type ah microcontroller is there now ah after seeing all these examples ah let us talk a little about what is the future of mechatronics the course which we are ah going through studying okay so the growth in mechatronic system ah definitely ah will be failed by the growth in the constituent areas ok so the constituent areas are actuators sensors and the microcontrollers so advancement uh in traditional discipline fuel the growth of mechatronic system by ah providing the enable enabling technologies for example ah invention of the microprocessor had a profound effect on the redesign of mechanical system and design of the new mechatronic systems we should expect continuous advancement in ah as i said cost effective microprocessor and microcontrollers then the sensors and actuator development enabled by advancement uh in applications of say mems adaptive control methodology methodologies and real time programming methods networking and wireless technologies and mature ca technologies for advanced system modeling virtual prototyping and testing so these days um you see we have further advance with what we call it as the internet of things okay which has come basically with with the development of networking and wireless technologies and ah these are these our many of the mechatronic systems ah have ah become ah controllable uh with the help of this the continued rapid development in these areas will only accelerate the pace of smart product development and as i said internet is a technology that when utilized in combination with wireless technology that may also lead to the new mechatronic products ok and ah while as i said earlier auto mobile sector has been one of the ah biggest sector which patternized the development of the mechatronic systems so the automotive products will further fuel the growth of mechatronic development there are numerous example of intelligent system in all walks of life as i said earlier including your smart 4 appliances such as dishwasher vacuum cleaner microwaves and wireless network enable devices further in the area of human friendly machines we can expect advances in robot assisted surgery ah currently we are using ah say the davinci ah for the surgery purpose ah and it has replaced ah one can say that the laparoscopic surgery and now surgery ah can be done ah very easily and further women friendly machines can be made with implantable sensors and actuators other areas that will benefit from mechatronic advances may include robotics manufacturing space technology transportation and so we can conclude that the future of mechatronics is wide open and there is a definite need to study ah this course and ah try to understand how the more and more mechatronic products could be developed now ah before making any mechatronic product ah as you know if you may want to make a product you need lot of resources in terms of time and money has to be spent ok so that resources we can use judiciously by going through the mechatronic system simulation okay so the mechatronic system design are complex by nature as we have seen and are becoming more complex ah day by day and as a system design grows in overall size to accommodate ever increasing demand for functionality and performance these design must integrate your analog and digital hardware as well as software that controls them okay and mechatronic system behavior is determined by inter dependencies ah between the different components as ah these components ah has to be ah controlled ah or of the inputs has to be taken and output has to be given ok so therefore an integrated and interdisciplinary engineering approach is necessary okay so for this region engineers must be assisted by tools which allows a system analysis with respect to capabil capabilities capacities and behavior without really constructing the system okay so that without actually making the system we should be able to see the behavior of the system okay and hence comes the need for appropriate modeling and simulation tool for the mechatronic systems so here are some of the references which you can look for further study about this i have talked about these references in my ah first lecture also that is ah there is a very good book on mechatronics by ah bolton ah and another by elsiatore ah by shetty ah bishop as well as you can look at our book also where you will find more of the simulation tools for the mechatronic system so ah in this lecture we have seen ah the examples of the mechatronic ah systems and so we have seen the engine control then we have seen the photocopier copy machine we have seen the lego nxt example we have seen the ah legged robot example and we have also seen the stepper motor control as well as the ah dc motor control there could be many more ah numerous examples as i said ah this example could be ah say your dishwasher in your house it is the automatic washing machine ah is there ok the vacuum cleaner in your house is there okay so as an exercise you can take ah just look at this system and identify how these ah systems work and what are the various actuators ah which are used here what are the various sensors which are used here and ah what are what type of ah controller either microprocessor or microcontroller is being used here okay ah thank you and next lecture we will take up ah again some of the basics before we actually move on ah to the actuators and sensors which are used in the mechatronic system we will be looking at some of the basics so i will be talking about ah some basic concept of electrical engineering electronics engineering and then ah we will move on to the our next topic thank you [Music] [Applause] [Music] hey [Music] you