Contents

• I. Background
  • 1. Programming Robots
    • 1.1 Robots
    • 1.2 Robot Behavior
    • 1.3 Our Scope
  • 2. Tools for the Class
    • 2.1 Free Software
    • 2.2 Windows Platforms
      • 2.2.1 Getting the Software
      • 2.2.2 Setting up and Testing
  
  
• II. Basic Input/Output and Peripherals
  • 3. Binary Input/Output
    • 3.1 Hardware Aspects
    • 3.2 Configuration
      • 3.2.1 Including header files
      • 3.2.2 Naming convention
      • 3.2.3 ``Registers'' for the ports
      • 3.2.4 What is ``pull up''?
      • 3.2.5 Configuration code
    • 3.3 Common Input Techniques
      • 3.3.1 Edge Sensing
      • 3.3.2 Debouncing
  • 4. The Timer Device
    • 4.1 Functions
      • 4.1.1 As a Stopwatch
      • 4.1.2 As a Source of Periodic Tick
      • 4.1.3 Pulse Width Modulation (PWM)
    • 4.2 ATMega128 Timer Configuration
      • 4.2.1 Timer Configuration
      • 4.2.2 PWM Configuration
  • 5. Interrupts and Interrupt Service Routines
    • 5.1 Concept
      • 5.1.1 The global interrupt enable flag
      • 5.1.2 The interrupt vector
      • 5.1.3 Interrupt service routines
      • 5.1.4 Writing an ISR
      • 5.1.5 But what about INTERRUPT?
    • 5.2 Timer ISR
  
  
• III. Basic Open Loop Motor Control
  • 6. Stepper Motors
    • 6.1 Concepts
      • 6.1.1 Full Stepping
      • 6.1.2 Half Stepping
      • 6.1.3 Software Control
    • 6.2 Frequency Division
    • 6.3 Displacement, Velocity and Acceleration
      • 6.3.1 Displacement
      • 6.3.2 Velocity
      • 6.3.3 Acceleration
      • 6.3.4 Getting back to Displacement
      • 6.3.5 Physical Parameters
      • 6.3.6 Velocity Profile
      • 6.3.7 C code framework
      • 6.3.8 What about differential steering?
      • 6.3.9 Implementational Alternatives
    • 6.4 Coding Tips
      • 6.4.1 Efficiency issues
  • 7. Project 1
    • 7.1 Final Objectives
    • 7.2 Step by Step
      • 7.2.1 Set up the Tools
      • 7.2.2 Input/output
      • 7.2.3 Frequency Division and Velocity
      • 7.2.4 Acceleration and Deceleration
      • 7.2.5 Displacement Control
      • 7.2.6 Handle Negative Displacement and Velocity
      • 7.2.7 Add Left and Right Motors
      • 7.2.8 Add Angular Control
    • 7.3 Due Date and Grading
    • 7.4 How to Turn it In?
  • 8. R/C Servo Motors
    • 8.1 Concepts and Rationale
      • 8.1.1 Components of an R/C Servo
      • 8.1.2 Control Mechanism
      • 8.1.3 Why use R/C servos?
    • 8.2 Modification for Full Rotation
    • 8.3 PWM Control
    • 8.4 Issues and Tips
      • 8.4.1 Poor Speed Control
      • 8.4.2 Uneven Full Rotation
      • 8.4.3 Fragile Plastic Gears
      • 8.4.4 Not Meant for Continuous Use
  
  
• IV. DC Motor and Closed Loop Motion Control
  • 9. DC Motor Control
    • 9.1 DC Motor Direction Control
    • 9.2 DC Motor ``Strength'' Control
      • 9.2.1 Analog Electrical Potential Control
      • 9.2.2 PWM
    • 9.3 Are we done?
  • 10. Motion Encoding
    • 10.1 Optical Encoding
    • 10.2 Magnetic Encoding
    • 10.3 Quadrature Encoding
    • 10.4 Implementation
      • 10.4.1 General Approach
      • 10.4.2 External Interrupts
      • 10.4.3 Algorithm for Quadrature Encoding
    • 10.5 Electronic Interface
      • 10.5.1 Problems with a plain phototransistor
      • 10.5.2 Solution
      • 10.5.3 Example
  • 11. PID Loop
    • 11.1 The Theory
      • 11.1.1 The Proportional Term
      • 11.1.2 The Integration Term
      • 11.1.3 The Derivative Term
    • 11.2 From Continuous to Discrete
    • 11.3 Practical Concerns
      • 11.3.1 Resolution of Output
      • 11.3.2 The Resolution of $e(t)$ and $K_{p}$
      • 11.3.3 The Resolution of the Integration Term
      • 11.3.4 The Resolution of the Differential Term
    • 11.4 Improving Feedback Resolution
      • 11.4.1 The Problem
      • 11.4.2 A Solution
      • 11.4.3 Practical Considerations
  • 12. Motor Driver Circuit Design
    • 12.1 TPIC0108 Interfacing
      • 12.1.1 TPIC0108 Logic for DC Motors
      • 12.1.2 TPIC0108 Logic for Stepper Motors
      • 12.1.3 TPIC0108 Chopper Drive Logic
    • 12.2 Layout Considerations
  
  
• V. Reading Sensors
  • 13. Analog to Digital Conversion
    • 13.1 Configuration
    • 13.2 The ADC clock
      • 13.2.1 Voltage Reference
      • 13.2.2 Multiplexer Selection
      • 13.2.3 Free Running versus Manual
      • 13.2.4 Interrupts
      • 13.2.5 Enabling and Starting
      • 13.2.6 Bit Positions
      • 13.2.7 Reading Results
    • 13.3 Common Techniques
      • 13.3.1 One-shot ADC Read
      • 13.3.2 Free-running Background Update
      • 13.3.3 Server-client Approach
  • 14. IR Ranging Sensor
    • 14.1 General Information
    • 14.2 Interface
    • 14.3 Important Notes
      • 14.3.1 Stablizing the Supply Voltage
      • 14.3.2 Debouncing
      • 14.3.3 Sampling Frequency
      • 14.3.4 Inter-measurement Filtering
      • 14.3.5 Distance Noise Prediction
  
  
• VI. Communication
  • 15. General Communication
    • 15.1 Reasons
      • 15.1.1 Program update
      • 15.1.2 Remote control
      • 15.1.3 Debugging and Logging
      • 15.1.4 Environmental Interaction
      • 15.1.5 Inter-robot Interaction
    • 15.2 Devices
      • 15.2.1 RS-232, asynchronous
      • 15.2.2 RS-485
      • 15.2.3 Ethernet
      • 15.2.4 Wifi
      • 15.2.5 Bluetooth
  • 16. Low-Level Asynchronous Communication
    • 16.1 Timing Details
      • 16.1.1 Start Bit(s)
      • 16.1.2 Data Bits
      • 16.1.3 Parity Bit
      • 16.1.4 Stop Bit
    • 16.2 The USART
      • 16.2.1 Clock and Transmission Speed
      • 16.2.2 Frame Format
      • 16.2.3 The Ninth Bit and Networking
      • 16.2.4 Errors
      • 16.2.5 Interrupts
      • 16.2.6 Enabling and Disabling
    • 16.3 Circular Queues as Software Buffers
      • 16.3.1 An Example: Circular Queue
      • 16.3.2 Where is the Array?
      • 16.3.3 The Record Structure
      • 16.3.4 Logic for a Circular Queue
    • 16.4 Circular Queue Implementation
      • 16.4.1 cq.h
      • 16.4.2 UART ISR Logic
      • 16.4.3 UART API
  
  
• VII. Robot Behavior
  • 17. Threading
    • 17.1 Life without Multithreading
  
  
• VIII. Project
  • 18. Project
    • 18.1 Robot Objectives
    • 18.2 Robot Specifications
    • 18.3 Design
      • 18.3.1 Drive Platform
      • 18.3.2 Fire Extinguisher Subsystem
      • 18.3.3 Sensors
      • 18.3.4 Communication Subsystem
      • 18.3.5 Battery and Power Subsystem
      • 18.3.6 Control Units
  
  
• IX. Robot Design Log
  • 19. Robot Design Log
    • 19.1 Design Requirements
      • 19.1.1 Physical
      • 19.1.2 I/O
      • 19.1.3 Software (added 20040307)
    • 19.2 Components
      • 19.2.1 Pin count
      • 19.2.2 Component Selection
      • 19.2.3 Mini-Sumo Chassis Design
    • 19.3 Design (added 20040307)
      • 19.3.1 Bootloader (added 20040307)
      • 19.3.2 H-Bridges
      • 19.3.3 (20040322) RS232
    • 19.4 PCB Design Log
      • 19.4.1 20040410
      • 19.4.2 20040406
      • 19.4.3 20040404
      • 19.4.4 20040331
      • 19.4.5 20040322
    • 19.5 Drive System
  • 20. A.N.T.
    • 20.1 GPS
      • 20.1.1 Interface
    • 20.2 Stereo Vision
      • 20.2.1 Theory
      • 20.2.2 Equipment
  • 21. Project Log
    • 21.1 20050525
    • 21.2 20050525
      • 21.2.1 Interface to oil submerged box
      • 21.2.2 Components
    • 21.3 20050129
    • 21.4 20040326
    • 21.5 20040319
    • 21.6 20040318
  
  
• X. Work In Progress
  • 22. DC Motor Encoding
    • 22.1 The EMF
    • 22.2 The Problem
    • 22.3 The Solution
    • 22.4 Detecting Circuit Open
    • 22.5 Detecting Circuit Closure
    • 22.6

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