The Splatbot competitions featured autonomous robots which attempted to shoot each other with paintballs. These robots were equiped with 5 paintballs each to fire at the opposing robot.

The concept was conceived in May of 2001. Three teams were formed at a meeting in June (see message #541). The Downtown Team disbanded by July and the remaining 2 teams worked on the robots through the summer and into the fall. The technical demo was on Oct 14th, and the competition was a week later.

After a long break, the IR detection scheme that had proved troublesome was replaced by lasers. The next competition was on June 20, 2002. That also turned out to be the last competition.

A year later, interest was renewed, but with Nerf darts instead of paintballs. The "Nerfbot" was born. See the Nerfbot section for information.

Splatbot 2002

For results see messages starting with #2136

Splatbot 2001

Rules for the 2002 competition

Robot Control:

The robots must be fully autonomous, NOT remote controlled. The brains of the robot must be fully contained on the robot. RF links to the robot are allowed, provided that this link is only transmitting from the robot, not receiving.

Robot Size Specs:

The robot must be a minimum of: base = 10 inches diameter, height = 15 inches from the ground.


This area must have some sort of surface that a paintball can physically hit. That surface can be made of anything: It can be a simple as fabric, or as complex as extruded aluminum. This cylinder area must reach to within 4 inches of the ground.

There is no maximum robot size, or maximum robot speed. The robot must be able to move though, and must move at least 20 feet during a match with at least one turn of 90 degrees.

Your robot must start as one fully contained machine. After the match starts, the robot can break apart and have several separate sections doing different things. At the completion of the match, the robot must be able to reassemble by itself. Yes, you could drop high speed rovers with sensors... seek out the opponent and tell the main body where to go to kill the opponent. A paintball hit on any one of the pieces constitutes a hit. Only one section can have the paintball weapon.

Paintball Gun Position On The Robot:

The paintball gun must be placed no higher than 14 inches from the ground, and must be mounted either horizontally or pointing at a downward angle.

The robots will be limited to 5 shots. This could be 5 guns or 1 gun that reloads.

Paintball hits:

Your robot is considered hit if a paintball from the other robot hits you. It doesn't matter is the paintball breaks when it hits your robot or not. ie- don't bother coating your robot in soft foam or something.

In order for a hit to count, the paintball must hit the robot intact. ie- splattering paint from a muzzle will not be counted as a hit.

Rules for laser detection scheme:

Lasers will be used for the robots to detect each other. Other detection schemes can be used on each robot, but all the robots must have the necessary reflective tape mounted on it so that the other robots can find them.

1) Several 2 inch wide strips of reflective safety tape must run vertically from 4 inches to 20 inches on each robot. The vertical stripes do not have to be contiguous. The vertical stripes can rotate at up to 1000 rpm.

2) This reflective tape must be visible horizontally at a range of 2 feet from the robot (at any position around the robot parallel to the robot from 4 inches to 20 inches in height) with a maximum angle of incidence of 45 degrees.

3) The tape does not have to be mounted on a flat surface. If it is mounted on a curved surface, that curve cannot have a radius of less than 1.5 inches.

4) There can be no more than 2 breaks in the reflective tape vertically. Each break must be less than 1/2 of an inch in height. There must be at least 2 inches between the 2 breaks.

5) The laser output cannot leave the robot shining above horizontal. In other words, if your laser is mounted at 18 inches on the robot, the output must never reach above 18 inches at any distance from the robot.

6) The laser transmitters must have a maximum output power of 5 mW or less with the additional requirement that the irradiance of the laser beam should not exceed 25 W m-2. Most laser pointers meet this criteria.

7) The laser mounting/robot design must be such that the laser output must never shine above 3.5 feet at 100 feet. This means that the robot itself could not tilt more that 12 degrees over any sort of terrain. The arena floor itself is reasonably flat, so that is not normally a large consideration. The rules is more to avoid unreasonably 'tippy' robots that might fall over during competition due to a bump from another robot.

The intent of the laser rules is twofold:
1) Avoid shining lasers into anyones eye. Safety is the most important factor to consider when you are building your robot. Any robot that is deemed to be a safety risk will not be allowed to complete.

2) To ensure that the robots will be able to see each other. This is what the competition is all about. It's much more fun when they see each other and are firing shots around the arena. This allows strategy to become much more important (ie- hiding behind walls, etc...) Having a robot which bends the rules or utilizes a loophole is no fun for anyone. On the other hand, feel free to push the limits and have a unique design. You may kick some *ss the first time, but the other robots will be ready for you next time.

Arena Specs:

The arena will be approx. 30 feet by 50 feet long. It may either be indoors on wood flooring or concrete or could be outdoors on pavement or concrete, but will be reasonably flat. There will be 5 obstacles in the arena. Four of these obstacles will be 3 feet high and 4 feet long, and one will be 3 feet high and 6 feet long. They will be painted off-white in a flat paint. 2 of the smaller obstacles will be placed at either end of the arena, and the large one one in the centre of the arena. Regardless of the arena (whether it be skating rink, mesh paintball tent or parking lot), the boundaries of the arena will be marked with a 3 inch wide white chalk mark. Your robot will not be allowed to fully cross that boundary. You can cross it partially, but not completely. This means that you'd better have some sort of detection circuitry on the base of your robot looking for this, or just count on being lucky.


Scoring:

Each round of competition will last 10 minutes, with up to four robots fighting against each other at the same time. A winner will be declared based on successful hits, overall aggressiveness and design creativity. For instance, in the absense of any paintball hits, a search-and-destroy robot would gather more points than a robot that camps and waits for an opponent to come into range.

Misc:

No cheating. You know what I mean... if you come up with something that skirts the rules due to an oversight, you'll be busted. There is a fine line between smart/inventive design and gaining an unfair advantage due to holes in the rules. I encourage everyone to push the limits, but if you know deep down that you are skirting the rules, don't do it.