Rules

Robot Combat Rules

Robot combat has several organizations that develop rules of play. These rules typically cover both robot construction and match procedures. However, in the USA there is no national league or governing body defining local rules. The sport is still young, and each event can choose its own rules, experiment, and innovate.

Good rules ensure fair fights, impartial judging decisions, and most of all, uniform standards of safety.

Standardized rules

Here are some of the organizations which have published rules and guidelines for robot combat events. You can freely download and read any of these rules.

• Standard Procedures for the Advancement of Robot Combat, publisher of numerous resources for arena construction, competitors, judges, and more. These are the most commonly used rules for SPARC Robot Construction and SPARC Match Procedures. Event organizers discuss SPARC rules changes regularly.
  Note: Site temporarily down at beginning of 2024
• Northeast Robotics Club, a prominent competitive organization - NERC Rules
• Fighting Robot Association is centered in the UK - most events in Europe use their FRA Rules
• National Havoc Robot League has their own NHRL Rules
• BattleBots is a TV show with 250 pound fighting robots - BattleBots Rules are adjusted yearly

(National Robotics League is not on this list because only students on authorized teams may participate.)

Local rules

When building your robot, decide which events you plan to compete in, learn which standard rules are in use, and check for exceptions or changes to the rules that may affect you. Generally events are locally run, and each is different, with rules adapted to the local requirements and situation, including the event venue, number of available volunteers or workers, and arena type.

• Arenas - For many bot builders, travel to multiple locations to compete isn't practical. Consequently, multi-city leagues are unusual, and unlike football, the arena of play is not standardized. Some arenas have metal floors, some wood; some will have pits or fences, while others do not; some arenas have thick, heavy polycarbonate windows while others can safely contain only bots with lower total weapon energy.
• Venues vary as well; for example, many if not most local clubs meet in event spaces where open flame isn't allowed, preventing the use of fire weapons. The use of power tools may be restricted to a safe area or even banished to the outdoors.
• When Volunteers are scarce or unavailable, the event may be streamlined in various ways, such as simplified judging (see below).

Judging Systems

There are several different methods to judge a robot combat match.

Generally, if a robot is disabled, thrown out of bounds, or unable to travel normally on the arena floor, the judges will determine that the robot has lost the match.

If neither bot is disabled or disqualified, judges must render a decision. This is usually done with a point system weighted to bring out the best in bot designers and drivers, but designed never to result in a tie. For example, judges under SPARC rules give points for Aggression (5 points), Damage (6 points) and Control (6 points), but shared between two opponents.

If both robots appear to have suffered equal damage, each would receive equal points (3 each) using the SPARC rules. If both also exhibited equal control ability, both would receive 3 points. The judges must weigh which driver was the more aggressive to break the tie. However, it's possible on some point scoring systems for 2 of 3 judges to believe one robot has won, but the 3rd judge assigns enough points to override them.

SPARC offers example videos with judges commentary that can help new judges understand how to assign scores.

Edge cases

Event organizers may make exceptions for specific issues caused by the arena itself. For example, if bots gets jammed against the walls due to a design flaw or normal arena wear and tear, judges may direct opponents to stop the match and free a bot that gets stuck instead of counting that bot out of play. The bot's driver is expected to avoid that situation in the future.

A "one free unstick" rule may also apply to bots that have become entangled or locked together.

Judge's Call variant

Many events have done away with the detailed scoring system and simply have each judge indicate which bot they felt won the overall match. While this may lead to more consistent results, some builders get frustrated without scores to indicate why they won or lost the match. Different events also have different allowances for judges to talk with each other when making decisions. Some events want each judge to come to their own conclusions independently, while others think it better to have judges compare notes and discuss the results.

Outcome variant

Matches can also be judged by a simplified system based solely by the state of the robots at the end. For example:

• 2 points awarded to the survivor when the other bot is knocked out, disabled, or falls into a pit (Win)
• 2 points awarded if the opponent is disqualified or forfeits the match before it starts (Bye)
• 1 point awarded to each bot remaining after time expires and the match is over (Tie)
• 0 points for a bot that is knocked out, disabled, or falls into a pit (Loss)
• 0 points awarded to a bot that is not ready for combat or is disqualified (Forfeit)

This system is ideal for informal matches and usually doesn't require impartial judgment. However, it's important that the term "disabled" is clearly defined and understood by all participants.

Since all types of bots must be able to disable their opponent, it's best if this variant is played in an arena with pits or other hazards that will potentially allow wedge bots and partially damaged bots a chance to win.