Chapter 8 Summary

This chapter used the infrared IR LED/receiver pairs for simple distance detection, to make a BOE Shield-Bot shadow vehicle.  Now-familiar skills combined with some new concepts got the job done:


  • Looking at the IR receiver’s peak sensitivity
  • Exploiting the IR receiver’s sensitivity curve properties with a frequency sweep to detect distance
  • Changing series resistor values to match up the sensitivity of two IR LED receiver pairs—making an adjustment in hardware


  • Writing a routine with an indexing for loop to generate a frequency sweep
  • Writing a sketch that uses proportional control loops
  • Using const int to set up a proportional control loop’s set point and proportionality constants
  • changing a control loop’s proportionality constants to fine-tune the control system—making an adjustment in software
  • What sampling rate and sampling interval are, and how they relate to each other

Robotics Skills

  • Setting up a closed-loop proportional control system with a processor, sensors and actuators for autonomous shadow vehicle navigation

Engineering Skills

  • Reading a block diagram for a simple closed loop proportional control system, with a summing junction and operator blocks
  • Understanding and using a closed loop control system’s set point, error, proportionality constant, and output value
  • More subsystem testing and troubleshooting