Build Your Own Combat Robot

Chapter 11: Autonomous Robots 241
the human brain, of which more than half is devoted to processing just what the
eyes see. The rest of the brain does everything else.
The human eye-brain combination can easily spot a robot in a combat arena and
know where it is, what direction it is going, how fast it is going, its motion relative to
another robot’s motion, where the hazards are, and where the perimeter of the
arena is. The human eye-brain can do human intuitive things, such as calculate how
heavy an opponent is and how dangerous it might be, and determine the weak
points to attack and when to retreat and regroup. The human brain can do this all at
once—plus throw out any information that is not needed for the task at hand. The
eyes of a robot break the image it sees into picture elements, or pixels. A robotic vision
systems has to interpret everything it sees, pixel by pixel, on the vision camera
and then make decisions on it. Teaching a robot how to distinguish the difference
between a steel box and an enemy robot is a challenging task. Research scientists
around the world are still getting PhD’s trying to figure out how to implement a reliable
vision system in robots.
Though vision systems are rather complex to implement, autonomous robots
are still possible. For example, longtime combat robot builder Bob Gross
built a beacon system that can be placed on a robot allowing it to see where the
opponent is in the arena. (See the sidebar “Bob Gross and Thumper,” later in
this chapter, for more information.)
Because every robot design and function is different, this chapter cannot provide
the exact details on how to implement a sensor into your robot. What this chapter
will cover, however, is the basic functionality of how various sensors work.
Because a specific sensor may have performance characteristics based on how it
is implemented and the environment in which it is being operated, the robot builder
should build a prototype sensor system and fully test it before implementing it into
the robot. When using semiautonomous to full-autonomous components in your
robot, testing is critical. It is best to build small-scale prototype models to test the
various components and all of the failsafe features before implementing them in the
final robot. All the bugs need to be worked out prior to a combat event. When at an
event, you will have to demonstrate these features and the corresponding safety features
to the safety inspectors; and you’ll need to convince them that these features
are reliable, or you won’t be allowed to compete. Because of this, more time before
the contest is required to test the robot and the advanced controls.
Using Sensors to Allow Your Robot to See, Hear, and Feel
Before implementing semiautonomous features in a robot, you need an understanding
of how sensors work so that the appropriate sensor can be selected for
the application. A multitude of sensors can be used by a robot to react to its environment.
This chapter will cover some of the most common sensors used in robots.
Most of these sensors break into two categories: passive and active sensors.