Lecture on Models and Modeling

Introduction to Models

• Definition: A model is an abstract representation of a system, simplifying by eliminating unnecessary details to focus on relevant attributes.
• Purpose of Models:
  • Aid understanding for better decision-making.
  • Improve communication about system designs.
  • Facilitate collaboration.
  • Allow analysis, simulation, and efficiency in the design process.
  • Enhance design quality and reduce costs.

Types of Models

• Block Diagrams:

  • Useful for modeling structure of systems.
  • Example: Attitude control and maneuvering system of the Gemini spacecraft.

• Textual Models

• Graphical Models

• Mathematical Models

• Physical Models

• Computer Models

Flowcharts

• Purpose: Graphical models focused on the behavior of a system.
• Components:
  • Circles/Ovals: Start or end of a process.
  • Rectangles: Steps in a process.
  • Parallelograms: Input or output.
  • Diamonds: Decision points.
• Example:
  • Visit to a doctor's office flowchart.
  • Euclid's greatest common denominator algorithm.

Finite State Machines (FSMs)

• Characteristics:
  • Graphical and abstract models.
  • Model discrete dynamic systems with finite states and transitions.
  • Example: Light switch system.
• Components:
  • States: Represented by circles.
  • Transitions: Directed arrows.
  • Events: Label transitions.
• Use Case:
  • Modeling a door system with state diagrams and state transition tables.
  • Converting models into programming languages like Python or Java for system control.

Complex FSM Example

• Garage Door System:
  • Functional block diagram with components: button, controller, motor, limit switch.
  • State diagram to model opening, closing, and safety features.
• Additional Complexity:
  • Incorporating safety features like an infrared beam interrupt.

Robotics Application

• Problem: Programming a robot to solve a maze.
• FSM Solution:
  • Define states: moving forward, turning left, turning right.
  • Events: bump detection, wall detection.
  • Create a state diagram to enable the robot to navigate a maze.

Analysis

• Use of Models: To analyze and predict system behavior and problem-solving capabilities of systems like robots in mazes.

Conclusion

• Models are crucial for simplifying complex systems, enhancing understanding, and facilitating the design and implementation of various technical solutions.