RobotClasses
To keep matches fair, robots compete against others that are in a similar "class." The most common distinction is the weight class. Builders must be aware of which classes are allowed in the events they participate in. Some robot classes are very popular while others are very rare; before you build a 6lb Mantisweight bot be sure that your chosen event runs that weight class.
Weight Classes
Weight class restricts the maximum fighting weight allowed for a robot.
Caution: The terms "Antweight" and "Beetleweight" differ across event regions as shown below.
| Class | SPARC (USA) | FRA (UK) | Special |
|---|---|---|---|
| Fleaweight | 75g | -- | -- |
| Fairyweight | 150g | -- | -- |
| Antweight | 1lb | 150g | -- |
| Beetleweight | 3lb | 1.5kg | -- |
| Mantisweight | 6lb | -- | -- |
| Dogeweight | 15lb | -- | National Robotics League |
| Featherweight | 30lb | 13.6kg (30lb) | -- |
| Lightweight | 60lb | 30kg | -- |
| Middleweight | 120lb | 55kg (121lb) | -- |
| Heavyweight | 220lb | 110kg | -- |
| TV-Heavyweight | 250lb | -- | BattleBots® |
Often weight bonuses will be offered for specific design features. For example, SPARC rules allow for bots to be up to 50% heavier for bots which shuffle instead of roll, or double weight for bots which fully qualify as Non-Wheeled. Likewise, BattleBots heavyweights can currently be up to 500.0 pounds if they can walk using articulated legs, and meet a number of other design criteria.
Weight classes may include size restrictions; for example, 150g Antweight (UK) is generally required to fit within a 100x100x100mm cube. Read the event rules for details.
Weapon Restricted Classes
These robot classes align with an existing weight class, but have further restrictions on what weapons can be used as well as other possible restrictions on things like using ground-scraping wedges. These are often chosen for events where they don't have an arena that can safely contain a full-combat robot; for example, spinning weapons may be forbidden, or limited in kinetic energy.
Before entering this type of competition, please read your event's rules to understand the restrictions.
- 150g (Non-destructive)
- 12lb (Tabletop)
- 12lb (Sportsman)
- 30lb (Sportsman)
- 30lb (Tabletop)
- 60lb (Sportsman)
- 250lb (Sportsman)
Non-destructive
Robots in non-destructive classes are not allowed to use saws, piercing weapons, fire, etc. to damage other bots. Flipping, throwing, and impact damage are permitted, and there is normally a pit available so that robots with wedges can knock their opponents out of the arena. This is ideal for builders who don't want their creations so easily destroyed.
Other classes in the same event may be labeled "destructive" for clarity.
Construction Restricted Classes
These classes place restrictions on construction materials and methods.
Plastic Ant
In an effort to make robot building more accessible the plastic antweight class was started by Western Allied Robotics. These robots are primarily 3d printed but can be fabricated out of approved plastics. The robot class became popular and the rules were adopted by Sparc.tools.
Termiteweight
There are kits to construct combat robots from laser-cut wood pieces. They have all the parts needed to construct the robot and the transmitter, but no spares in case of damage. This type of bot is humorously known as "termite weight," and while they could in theory be entered into organized competition in the 1lb class, they have many serious disadvantages compared to normal 1lb opponents, such as plastic motor gears, lower battery capacity, and slower battery charging. Termite kits are fun, but are unlikely to succeed against more robust bots.
Lego
You can also build and fight combat robots built using Lego® bricks, motors, and remote controls, particularly within the Lego builders communities. Events like BrickCan Bots and BattleBricks showcase building Lego bots with many of the common combat robot weapons, with structures for optimal defense against hard impacts. These events often require the use of official Lego motors, which have plastic gearboxes which are easily broken, so this type of bot is unlikely to survive an encounter with a regular combat robot of a similar weight.
Technology Restricted Classes
Autonomous
This very unusual restriction requires builders to compete with robots that can find their opponents, drive themselves where needed, and make their own decisions about how to attack. Remote control of the robot is not allowed while the match is in progress. This can be done with simple sensors that cause the robot to travel all over the area and attack whatever they bump into. It is more effective using open-source machine vision, combined with either basic algorithms, machine learning, or even AI. Robotic mapping can be used to either use or avoid the arena boundaries to best effect.
Historic Weight Classes
120 lb was the competition class for high school and collegiate educational program BattleBots IQ. Later the program added a 15 lb Mini Class bot competition; 120 lb became Large Class
Heavyweight bots have historically varied from 100-110kg, and there was once a 340 pound Super Heavyweight Battlebots class.
This article covers much of the history of weight classes in robot combat.
Learn about the original 1999 Lego Robogladiators from Dan at Team Delta.