Micromouse Wall Follower Competition Rules

Techno Games 2002/2003

Introduction

The aim of this competition is to race a simple, self-contained Wall Following Micromouse robot vehicle around a known, standard walled course in the shortest time. This Wall Follower Micromouse competition is intended to act as an introduction to the international, 16 by 16 cell, maze-solving competition. The rules and specifications for this Wall Following competition are compatible with the rules and specifications for the international maze solving competition. It is intended that Wall Follower mice could be relatively easily modified to compete in the maze solving competition. The contest is a test of speed, wall sensing and steering control. Mice may be entirely mechanical, however it is expected that the fastest mice are likely to be electronically controlled. Mice do not need a micro controller or a memory for this competition. The mouse building skills required will, in general, include electronic, mechanical, and control system design.

A Wall Following Micromouse consists of a chassis, a drive system, a steering system and a power source. The standard micromouse baseboard and walls will be used to construct four 7x7 race tracks, one in each corner of a standard 16x16 maze, with a guard track separating each race track. This enables four mice to race against each other on separate tracks. Each mouse starts from a corner of the 16x16 maze and races on identically shaped tracks towards the centre of the maze. The wall configuration may incorporate left hand turns, right hand turns, 90? turns and 180o turns. Each mouse should follow the wall on its left hand side. Mouse builders can make a simple 7x7 single racetrack for developing their mice quickly and cheaply at home or at school.

The Race Track

1. The full sized 16x16 maze base, posts and walls are arranged to form four identical 7x7 racetracks. The walls are 50mm high and 12.5mm thick. The width of the track between walls is 168mm along its entire length. A simpler and cheaper method of construction for testing and development is to use walls without posts.

2. The walls and base may be made of plywood, medium density fibreboard (MDF) or similar material. The baseboard is painted matt black. The sides of the walls are painted satin or matt white. Alternatively the walls may be made using matt white laminated MDF. The tops of the walls are painted gloss red. The walls should reflect infra red light and the base should absorb it.

3. The dimensions of the competition track shall be accurate to within 5% or 5mm, whichever is less. Any assembly joints on the maze floor shall not produce steps of greater than 3 mm. The change of slope at any assembly joint shall not be greater than 4 degrees. Gaps between adjacent walls and posts shall not be greater than 3 mm.

The Mice

1. Mice may be of any height or weight. Mice may not exceed 250mm in length or width. Mice should therefore fit inside a 250mm by 250mm box.
2. Mice must be completely self-contained and should receive no outside assistance. Mice must carry their own power supply. This means that all batteries or other energy sources must be carried on the mouse and that the use of a catapult or other external propulsion or steering systems is not allowed. Only non-polluting power sources may be used, for example, clockwork, elastic or electric motors. Internal combustion engines are not permitted and external combustion systems such as steam engines are not allowed due to the safety hazard they might present. Umbilical cords, ultrasonic, infrared or radio control links are not allowed. Ultrasonic and infra red sensors are permitted. Batteries may be changed or re-charged between races.
3. Mouse handlers may not walk on or climb on to the baseboard. Mice should therefore be fitted with a lifting hook above the centre of gravity so that they may be lifted from a distant area of the baseboard with hook on a pole.
4. No mouse may mark the walls or base of the racetrack. The method of wall sensing must not be such as to exert a significant force on any wall likely to leave marks or cause damage. If the judges consider that a mouse has a high risk of damaging or sullying the maze they will not permit it to run. Nothing may be deposited in the maze. Mice must move along and around the walls; they must not jump or climb over the walls.
5. Mice may operate on wheels, caterpillar tracks or legs. Mice may be made from Lego, Meccano or similar construction kit systems.
6. Mice should be fitted with a timing light beam breaker flag of minimum size 25 mm square. This should be positioned near the front of the mouse and be 5mm above the baseboard level. This timing flag is to ensure that a reliable signal break is given to the optical timing equipment so that the mouse run can be recorded accurately. See Figure 1.

Figure 1 - Timing Flag Position

Teams

1. Teams may consist of any number of people.
2. No more than 2 mouse handlers are allowed to operate the mouse during the competition in order to avoid having a crowd at the circuit restricting the view of spectators.
3. Teams may enter any number of classes, but will normally only be allowed to enter one micromouse in each class.

The Race

1. Each mouse will start the race in their corner and will follow their left hand wall. The finish line is at the exit of the 7x7 square course. Mice will be timed for each race. Several races may be run if time, the number of entries and facilities permit.
2. The time taken to negotiate the track shall be measured either manually by the contest officials, or by light beams set at the start and destination. If light beams are used, the light beam sensors shall be positioned approximately 15mm above the base. 3. Scrutineers can apply a handicap, request a modification or reject a mouse if it does not comply with the rules, or if in their opinion it is has not been constructed or operated within the spirit of the competition.
4. Pre-race qualification will normally take place for all mice in order to ensure that mice are capable of competing in the race and to determine the running order for the main race(s).
5. Before the start of the racing the handlers should present their mice to the scrutineers for approval and registration whereupon the mice may be retained under the scrutineer’s supervision in the 'mouse park' until the start of the race. The mouse handler may be given 1 minute from the moment the mouse is taken from the mouse park to make any adjustments to the mouse. Only nominated mouse handlers may handle the mouse once the competition has begun.
6. Handling during a race will incur a touch penalty of five seconds for each nudge or assistance. The judges may add a five second time penalty for a false start or a restart. This penalty may be amended if in the opinion of the judges a fairer contest will result. If a mouse is elected to retire because of technical problems, the judges may, at their discretion, permit it to race again later in the contest.
7. A mouse entered for the Wall Following class may or may not be permitted to enter the Maze solving class, and vice versa. The decision will be taken by the organisers in the light of the number of entries and the time available for racing.
8. Under normal circumstances, no part of the mouse may be transferred to another mouse. The judges may allow a change of parts in exceptional cases, such as accidental damage.
9. The judges have the discretion to require a mouse to retire early for lack of progress, or if it is risking sullying the track.
10. The organiser may accept postal entries by prior arrangement for contestants from outside the UK or in other special circumstances. The organisers will take reasonable care to select handlers, if requested and agreed, and to return the mice to their owners. The organisers will not accept any responsibility for mice lost or damaged in any way. Such entries will only be accepted entirely at the risk of the entrant. It will be the responsibility of entrants to supply batteries, operating instructions and adequate packaging for both postal deliveries.
11. In the event of any dispute, the judges' decision will be final.
12. It is intended that the competition will be an educational and enjoyable experience for contestants and spectators. The judges will make any required judgement in the light of this overriding consideration.

Appendix 1

The maze construction

Walls should be satin or matt finish white with red gloss or matt finish tops. The base should be painted matt black using blackboard paint. The recommended matt black paint is either International or Signpost brand matt black blackboard paint, available in many DIY superstores.

Constructive comments on these rules and requests for clarification should be addressed to msmith AT iee.org

MCS12/9/02