Page 13 - The Unofficial Guide to Lego Mindstorms Robots
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This chapter describes the basic concepts of robotics and creates a backdrop for the MINDSTORMS product line. I'll also
cover different approaches to programming mobile robotics. Finally, I'll describe the RIS set itself. If you're in a hurry to start
building something, skip ahead to Chapter 2, Hank, the Bumper Tank.
What Is a Robot?
A robot is a machine whose behavior can be programmed. This is a broad definition—it includes things like VCRs and
microwave ovens, a far cry from the talking androids you might be thinking of. Robots have five fundamental components:
1. A brain controls the robot's actions and responds to sensory input. Usually the brain is a computer of some kind.
2. A robot's body is simply the physical chassis that holds the other pieces of the robot together.
3. Actuators allow the robot to move. These are usually motors, although there are many other possibilities, such as hydraulic
pistons.
4. Sensors give a robot information about its environment. A touch sensor, for example, can tell a robot that it has come in
contact with something else.
The last component is not always obvious:
5. A power source supplies the juice needed to run the brain, actuators, and sensors.
For example, think about a robot that spraypaints cars in a factory. Its brain is probably a garden-variety desktop computer.
The body is a big arm with a paint sprayer at the end. The actuators are motors or pneumatic pistons that move the arm around.
Position and rotation sensors are used so the robot knows where the sprayer is and what direction it's pointing. The whole thing
is plugged into a wall socket for power.
Mobile Robots
Mobile robots present special challenges. These robots can move their bodies around from place to place. Why is this
capability difficult? Many more things can go wrong if your robot is free to move around rather than being bolted to one place.
Being mobile multiplies the number of situations your robot needs to be able to handle.
