The Maze

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Story

You are trapped in an underground maze. It's completely dark, you can't see a thing. You feel your way along with one hand touching the wall next to you and the other hand stretched out in front of you, checking for a turn or dead end. Suddenly your front foot steps out into nothingness - a bottomless pit! How do you find your way out of this maze?

Objective

Your robot must find its way through a maze like the one described in the story. Since your robot doesn't have eyes, it's like being in total darkness. The objective is to find your way through the maze in the shortest time, avoiding bottomless pits. Each robot will have to run the maze in both directions, and your time will be the sum of the times in each direction.

Playing Field

The maze will be made out of Lego Mindstorms boxes and lids. The boxes may be placed in any pattern - you won't know how the maze is arranged until you arrive at the competition. But the maze will stay the same throughout the competition. The corridors in the maze will be at 9 inches wide or more.

The boxes will be arranged in right angle patterns as shown. The only gaps in the walls will be the entrance, the exit, and the bottomless pits. The floor of the maze will be light colored and the bottomless pits will be black.

Robot Construction

• The robot must be built from pieces in the Lego Mindstorms kit except for optional decorations.

• You can use extra motors and light sensors as needed

• There are no size or weight restrictions

• No glue or tape.

Rules

• To begin, the operator places the robot at one entrance to the maze, behind a thin pencil starting line.

• At the starting signal the robot operator will press the green “run” button and the clock will start.

• The robot must find its way through the maze without human intervention.

• If the operator touches the robot after the start, the robot must be returned to the starting position and the clock continues to run.

• Bottomless pits are represented by black construction paper at the end of a corridor. If a robot continues forward so that all four wheels are on the black paper, it falls into the bottomless pit. The operator may then return the robot the the starting position and the clock continues to run.

• The attempt is over when the robot passes a thin pencil line at the other end, or after 3 minutes have elapsed.

• Each robot will run the maze in both directions and the times will be added to obtain the total time.

Deciding the Winner

The winner is the robot with the shortest total time to successfully complete the maze in both directions.

Hints and Tips

This contest requires touch sensors and a light sensor. See examples and tutorials for ideas on how to solve this problem.

As you solve this problem you may discover that the robot will traverse the maze faster in one direction than the other. Why is that? Would it be possible to load two versions of the program and perhaps make some quick changes to the robot so the robot could take the fastest way through the maze in both directions?

Materials Needed

• 3-5 Lego Mindstorm boxes and lids

• A light colored floor or floor covering such as poster paper or vinyl fabric

• Black construction paper for the bottomless pits

Per team

• One Lego Mindstorms kit