TRBL Rules Summary

The TRBL rules set the weight limits, safety requirements and match format for every robot in the league. This page is an English summary of the TRBL Rulebook, revision of 14 September 2026.

Basic entry requirements

A robot can compete only if it meets all five conditions:

• it stays within the weight limit of its class,
• it meets every safety requirement,
• restricted systems were approved before the event,
• it has no banned features,
• it shows controlled movement and has an active weapon.

Weight classes and limits

A robot must not exceed its class limit at the start of a match.

Weigh-in: a robot more than 2.5 oz (about 70.9 g) over the limit cannot pass inspection. Every robot is weighed before each match. An overweight robot may fix the problem and be weighed again in the same session. If it is still over the limit, it is withdrawn from that match and its opponent wins. Weight violations do not give TKO points.

Teams that want a weight bonus must declare it before the tournament and have the design approved by the Organising Committee before registering. The bonus is added to the class limit, so a 3 lb true walker may weigh up to 6 lb.

Multibots

A team may enter a multibot of up to 4 parts. The parts count as one team robot, cannot start the match physically connected, and each part must move on its own. At least one part must carry an active weapon. The total weight allowance is the class limit plus 50% for 2 parts, 33% for 3 parts or 25% for 4 parts, split equally between the parts.

A robot that qualifies for both a locomotion bonus and a multibot bonus must choose one.

Safety requirements

Master power switch

Every robot needs a switch that cuts power to all weapon and drive systems, reachable without taking the robot apart and operable within 15 seconds with one hand. The power-off area must be marked with a sticker.

Failsafe

When the signal is lost, the transmitter is switched off or the link drops, power to drive and weapon systems must be cut within 1 second. This is tested at technical inspection by switching the transmitter off, and a robot that fails cannot fight. Each robot and each multibot part needs its own receiver.

Battery voltage

Anything above these values needs written approval from TRBL in advance. Lithium packs are charged with a balance lead and under supervision.

Weapon lock

Every weapon needs a solid lock that physically blocks movement and can be removed in one quick motion without putting fingers in the weapon path. The lock carries a label of at least 1" × 4" (2.54 × 10.16 cm) reading "Weapon Lock" or "Remove Before Fight", made of durable material. A robot without a lock cannot pass inspection.

Size

In an emergency the robot must fit TRBL's fire safety cart, about 23" × 23" × 44" (58.42 × 58.42 × 111.76 cm) inside.

Antweight rules

These rules apply to the Antweight (3 lb) class on top of the general rules, and take priority where they differ.

• The robot must fit within 300 × 300 × 300 mm at the start. Mechanisms that open during the match are exempt.
• Only LiPo, LiFe or NiMH packs are allowed, carried in a protected bay.
• A commercial 2.4 GHz radio system with binding is required. Wi-Fi and Bluetooth control are not allowed.
• Fire, liquids, powder, nets, adhesives, electrical discharge, lasers and radio jammers are banned in this class.

Systems that need approval

These systems are allowed only with approval from the Organising Committee. Apply at least 3 weeks before the event by writing to info@trbl.org.tr with technical documentation (schematics, CAD, parts list) and a safety procedure.

• Pneumatic and hydraulic systems.
• Internal combustion engines. The fuel tank is removed for weigh-in and a robot may carry fuel for at most 5 minutes of running.
• Flame systems. They must self-extinguish and shut off within 30 seconds of signal loss. Allowed fuels are propane, butane and isobutane, up to 177 ml for 3 lb and 473 ml for 12 and 30 lb robots. Oxygen-assisted systems are banned.
• Combustion-based and plasma-based heat systems (electric heaters need no extra approval).
• Spinning weapons with a tip speed above 483 km/h (300 mph), and projectile systems.
• Electromagnetic systems, which must use a weapon lock outside matches.

Banned features

No approval is possible for these. Robots that carry them cannot enter.

• Rocket motors, fireworks and airbags.
• EMP devices, radio jammers and electroshock weapons.
• Systems whose main purpose is to block the opponent's view (smoke or fog as a side effect of an attack is allowed).
• Systems that can cause harm outside the arena, such as high-power lasers, extremely bright lights or excessive noise.
• Parts designed to tangle an opponent's drive, such as wire balls, chains or nets.
• Detachable parts dropped to high-centre an opponent, and caltrop-style obstacles.
• Materials that foul the arena beyond cleaning, such as shot or gravel, or devices that cause permanent damage.
• Hazardous materials such as reactive alkali metals, harmful gases and radioactive substances.
• Magnets mounted to stick to the opposing robot.
• Spraying liquids from the robot (bubbles and liquids that quickly turn into gas or solid are allowed).

Match rules

Every match lasts 3 minutes and starts on the first "F" of "Fight, Robots, Fight!". During the countdown all parts must be unpowered and still. A robot that moves early gets 1 TKO point, or 3 if it made contact.

• Knockout: the referee starts a 10-second count for a robot that cannot move. The count stops if the robot moves by itself or the opponent touches it. For a multibot, the count starts when more than 51% of its parts cannot move.
• Tap out: a driver can end the match at once with the tap-out button on their side of the arena. A tap out counts as a knockout.
• Judges' decision: if the match reaches 3 minutes without a knockout or tap out, the judges decide.
• Technical knockout (TKO): a robot that reaches 3 TKO points in one tournament loses by TKO. TKO points do not carry over between tournaments.
• Pins: a pin counts after 5 seconds. The referee counts to 10, and after "release" the pinning robot must give its opponent room to escape.
• Unstick: each match allows one unstick by the house robot, usually within 25 seconds. It does not stop the match or protect the stuck robot from attack.

Judging

Three judges score every match on aggression (5 points), control (6 points) and damage (6 points). Each judge picks the robot with the higher total, and the robot picked by at least two judges wins. If a judge's totals are tied, damage decides first, then control. Aggression means the intensity and frequency of deliberate attacks with an active weapon. Robots that avoid combat lose points.

Tournament format

The format of each class depends on how many robots pass inspection and is announced before the tournament. Every robot is guaranteed at least three matches.

League points: a win by knockout or TKO gives 3 points, a win on the judges' decision 2, a loss on the judges' decision 1 and a loss by knockout or TKO 0. Ties are broken by head-to-head result, number of knockout wins, total judges' points and finally a draw.

Event day: inspection and repair time

Every robot must pass inspection before its first match: weapon lock, sharp edges, failsafe test, active weapon and controlled movement, power switch, multibot parts, weapon modules and weigh-in. A robot that fights without passing inspection gets 3 TKO points and loses immediately.

A team may ask for up to 10 extra minutes of repair time, at most twice per tournament. Extra time cannot be used before the first match of the day and must be requested at the pit table before normal repair time runs out.

Penalty points

A robot that collects 3 penalty points is disqualified from the event. Each of these gives 1 penalty point:

• Leaving a LiPo battery charging unattended.
• Having an unlocked weapon outside the permitted areas.
• Controlling a robot or running a weapon before the arena doors are closed.
• Working with hazardous materials outside the permitted area.
• Using grinding tools outside the grinding tent or workshop.
• Touching a running, unlocked weapon by hand.
• Coming to the arena side without a robot card or wristband.
• Not using the Robot Hazard Station according to the rules.

Appeals must be submitted in writing by the team lead to the Tournament Director within 30 minutes of the end of the match. A board of the Tournament Director and two Tournament Supervisors decides by majority vote.