They are positioned between adjacent street corners, effectively blocking a robot's direct path from one corner to the next. Wall sections are used to represent obstacles, such as hurdles and mountains, around which robots must navigate. Enclosed rooms, mazes, and other barriers can also be constructed from wall sections. Figure 1-2 shows some typical wall arrangements a robot might find in the world. The second kind of thing in the world is a beeper.
Beepers are small plastic cones that emit a quiet beeping noise.
They are situated on street corners and can be picked up, carried, and put down by robots. Some tasks require one or more robots to pick up or put down patterns made from beepers or to find and transport beepers. Figure 1-3 shows one possible pattern of beepers. Beepers are small so there can be several on a corner, and they don't interfere with robot movement. 1.2 Robot Capabilities Let's now shift our attention away from the robot world and concentrate on the robots themselves.