Robot combat

Not to be confused with Military robots.

A spinner-type robot attacks

Robot combat is a hobby/sport in which two or more custom-built machines use varied methods of destroying or disabling the other. As of today, in most cases these machines are remote-controlled vehicles rather than autonomous robots, although there are exceptions, particularly in the field of robot-sumo.

Robot Combat enjoyed a period in the public eye when several television shows broadcast the robot fights. Either the public or the TV network administrators lost interest, and the shows dropped from the airwaves. The most well-known of these shows were Battlebots, Robot Wars, and Robotica. Although the mainstream interest in robotic combat peaked with the airing of those shows, there are still dozens of smaller competitions around the USA and in other countries every year. Combat robots have received mention in the press and entertainment shows from time to time as well.

Robot builders may be of any age and come from any walk of life. The robots themselves can range from modified remote controlled toys weighing less than a pound to three-hundred plus pounds of exotic metallurgy and sophisticated electronics. Although building a combat robot can cost thousands of dollars and hundreds of hours, some schools use the construction of combat robots in their courses to teach mechanical design and technology. For schools that shy away from the violence of combat robots, there are robotic competition alternatives such as the cooperative competitions FIRST and BEST Robotics. Robot competitions such as RoboGames, offer a mix of combat and non-combat events.

History

Among the oldest robotic combat competitions extant in the United States were the "Critter Crunch" (founded about 1987) in Denver and "Robot Battles" (founded in 1991) based in the southeastern U.S.^[1] Both events were run by members of the "Denver Mad Scientists Society".

1994 - Marc Thorpe organized the first Robot Wars competition in San Francisco.^[2] Four annual competitions were held.

1997 - Rights to the Robot Wars name is transferred to British TV production company who produce the Robot Wars television series. Early seasons feature competitive games and obstacle courses as well as simple combat. The series aired 151 episodes across 12 series from 1997 to 2003. Special series were produced for the United States and the Netherlands.

1999 - Former Robot Wars competitors in the U.S. organize a new competition named BattleBots. The first tournament was shown as a webcast, with the second tournament shown as a cable 'Pay-per-view' event.

2000 - BattleBots is picked up as a weekly television program on Comedy Central. It would span five seasons ending in 2002.

2001 - Robotica appears on The Learning Channel as a weekly series. The format features tests of power, speed and maneuverability as well as combat. The show ran in three series, ending in 2002.

2002 - Foundation of the Robot Fighting League, a regulatory body composed of the organizers of robot combat events in the United States, Canada, and Brazil. The body produces a unified set of regulations and promotes the sport.

2004 - Robot Combat is included as an event at the ROBOlympics in San Francisco, California, with competitors from multiple countries.^{[3] [4]}

2008 - ROBOlympics changes it's name to RoboGames and, while most events are not combat related, Robot Combat is significantly featured.

Weight classes

Michael "Shaggy" Macht and Jason Brown review a combat robot in the pits of the 2007 Robot Battles competition in Atlanta, Georgia.

Robots come in all shapes and sizes, but there are certain defining lines that robots rarely stray across, thanks to official rules and practicality. The standard by which all combat robots are measured is weight; the everyday dilemma of the robot builder is to cram as much power into as little weight as possible. Robots can be as small as the 75 gram 'Fleaweight' class, and as large as the 340-pound 'Super Heavyweight' class. The common weightclasses^[5] are as follows:

• 75g- Fleaweight
• 150g- Fairyweight (UK - Antweight)
• 1 pound (454 g) - Antweight
• 1 kilogram (2.2 lbs) Kilobot (Canada)
• 3 pound (1.36 kg) - Beetleweight
• 6 pound (2.72 kg) - Mantisweight
• 12 pound (5.44 kg) - Hobbyweight
• 15 pound (6.80 kg) - BotsIQ Mini class
• 30 pound (13.6 kg) - Featherweight
• 60 pound (27 kg) - Lightweight
• 120 pound (54 kg) - Middleweight / BotsIQ Large class
• 220 pound (100 kg) - Heavyweight
• 340 pound (154 kg) Super Heavyweight

There are some international variations in weight class - for example, UK robot builders define the UK Antweight class limit as 150g.

Weight is a precious asset for robot builders. For the sake of diversity of design, the rules often give an extra weight allotment for robots that can walk rather than roll on wheels. Such robots are more difficult to construct and their drive mechanisms are heavier. Some builders opt to build walking robots, taking advantage of the extra weight to add more powerful weaponry at the expense of greater complexity and fragility.

Given the violent nature of robot fighting, safety is always the most important issue at robot events. Robot fights take place in a sturdy arena, usually constructed of steel, wood, and bulletproof clear Lexan plastic. The size of the arena varies by the weightclass of the robots that are fighting in it. Some large competitions that entertain many different weightclasses have more than one arena, because 1 pound antweights do not need 50 foot (15 m) wide arenas in which to fight, but 220 pound heavyweights do. Having multiple arenas allows the event to progress more quickly.

Competition rules set limits on construction features that are too dangerous or which could lead to uninteresting contests. Strict limits are placed on materials and pressures used in pneumatic or hydraulic actuators, and fail-safe systems are required for electronic control circuits. Generally off-limits for use as weapons are nets, liquid, radio jamming, high-voltage electric discharge, untethered projectiles, and usually fire.

The Robot Fighting League (RFL) was created in 2002 when several builders decided that robot combat needed standardization of rules and judging criteria^[6] The majority of robot combat events in the U.S. have become RFL members and have adopted their ruleset, but some event organizers oppose the direction in which the RFL is taking the sport and remain independent. The topic of event standardization has lent itself to a healthy amount of controversy since the RFL's inception.

The sport continues today despite the lack of television coverage. The size of the events has diminished, but there are scores of tournaments scattered throughout the United States, Canada, and the United Kingdom.

Combat robot weaponry and design

An effective combat robot must have some method of damaging or controlling the actions of its opponent while at the same time protecting itself from aggression. The tactics employed by combat robot operators and the robot designs which support those tactics are numerous. Although some robots have multiple weapons, the more successful competitors concentrate on a single form of attack. This is a list of most of the basic types of weapons. Most robot weaponry falls into one of the following categories:

• Rammer - Robots employing high-power drive trains and heavy armor are able to use their speed and maneuverability to crash into their opponent repeatedly with hope of damaging weapons and vital components. Their pushing power may also be used to shove their opponent into arena hazards. Rammers (AKA ‘Bricks’) typically have four or six wheels for traction and stability and are often designed to be fully operational when inverted. Robot Wars Series 6 champion Tornado and Series 7 Runner-up Storm II were effective rammers.
• Wedge - Similar in concept to a rammer, the wedge uses a low-clearance inclined wedge or scoop to move in under an opponent and break its contact with the arena floor – decreasing its mobility and rendering it easy to push off into a wall or hazard. The wedge is also useful in deflecting attacks by other robots. Wedges are also used to lift an opponent up to make the attack of another weapon more effective. A small wedge may be attached to the rear of a robot with other weaponry for use as a ‘backup’ in case the main weapon fails. The 1995 US Robot Wars middleweight champion Roadblock (1997).
• Spinner - Continuously rotating weapons are popular and varied. These use a dedicated motor to spin up a heavy bar, studded disc, or toothed cylinder (drum/eggbeater) and use it to strike the opponent with the kinetic energy stored in the rotating mass. The mass may spin on either a horizontal or vertical axis, although vertical spinners may have maneuverability problems due to the gyroscopic action of the weapon. The destructive potential of a well designed spinning weapon requires robust arena containment to prevent shrapnel being thrown into the audience. Three-time BattleBots middleweight champion Blendo was the first effective full body spinner.
• Thwackbot - A narrow, high-speed, two-wheel drive train attached to a long boom with an impact weapon on the end creates a robot that can spin in place at a high speed, swinging the weapon in a horizontal circle. The simplicity and durability of the design is appealing, but the robot cannot be made to move in a controlled manner while spinning without employing sophisticated electronics. The 1995 US Robot Wars lightweight champion Test Toaster 1 was a thwackbot, as were T-Wrex and Golddigger from the BattleBots series.
• Torque Reaction - A variant on the thwackbot is the torque reaction hammer. These robots have two very large wheels with the small body of the robot hanging in between them. A long weapon boom has a vertically oriented hammer, pick, or axe on the end. On acceleration, the weapon boom swings upward and over to the rear of the robot to offset the motor torque. When the robot reverses direction, the weapon will swing forcibly back over the top and hopefully impact the opponent. These robots are simple and can put on a flashy, aggressive show, but their attack power is relatively small. BattleBots 2.0 middleweight champion Chaos 2 and BattleBots super heavyweight champion Kan-Opener.
• Overhead Axe - Swinging a high-speed axe, spike, or hammer forcefully down onto your opponent offers another method of attacking the vulnerable top surface. The weapon is typically driven by a pneumatic actuator via a rack and pinion or direct mechanical linkage. The attack may damage the opposing robot directly, or may lodge in their robot and provide a handle for dragging them toward a hazard. BattleBots heavyweight runner-up and Robot Wars competitor edit] Prohibited weaponry

  Since the first robot combat competitions, some types of weapons have been prohibited either because they violated the spirit of the competition or they could not be safely used. Prohibited weapons have generally included:

  • Radio jamming
  • High voltage electric discharge
  • Liquids (glue, oil, water, corrosives…)
  • Open combustion (fire, explosives…)
  • Un-tethered projectiles
  • Lasers above 1 milliwatt
  • Visual obstruction
  • Halon - a specific fire extinguishing gas effective as a weapon in stopping internal combustion engines. Note that current rules do not specifically ban Halon as it is no longer commercially available.

  Individual competitions have made exceptions to the above list. Notably, the Robotica competitions allowed flame weapons and the release of limited quantities of liquids on a case-by-case basis.^[8]

  Arena hazards have also been granted exceptions to the list of prohibited weapons. Robot Wars in particular used flame devices both in the stationary hazards and on some of the roaming "House Robots".

  Unusual weaponry

  

  A robot housed in a dog house uses flame against a full body spinner opponent.

  A very wide variety of unusual weapons and special design approaches have been tried with varying success and several types of weapons would have been tried had they not been prohibited.

  • Entanglement Weapons - Several early US Robot Wars competitors sought to immobilize their opponents with entangling weapons. Nets and streamers of adhesive tape were both tried with mixed success. Entangling weapons were prohibited in Robot Wars and BattleBots from 1997 onward,^[9] but the Robotica competitions allowed nets, magnets, and other entangling devices on a case-by-case basis.^[10]
  • Flame Weapons - Although prohibited for use by competitors in Robot Wars and BattleBots, the rules for Robotica and the Robot Fighting League do allow flame weapons under some circumstances. RFL super heavyweight competitor Alcoholic Stepfather and Robotica competitor Solar Flare employed gaseous flamethrower weapons. Flamethrowers are not effective weapons, but are audience favorites.
  • Smothering Weapons – The BattleBots and Robot Wars lightweight competitor grappling hook.
  • Tethered Projectiles – Although tethered projectiles are specifically allowed and discussed in major rules sets, their use is quite rare. Neptune fought at BattleBots 3.0 with pneumatic spears on tethers, but was unable to damage its opponent. During a friendly weapons test, Team Juggerbot allowed the builders of Neptune to take a couple shots against their bot. One of two shots penetrated an aluminum panel below the main armor, while the other bounced off the top armor.^[11]
  • Multibots (clusterbots) – A single robot that breaks apart into multiple, independently controlled robots has appealed to a few competitors. The Robot Wars heavyweight edit] Unusual propulsion

    The great majority of combat robots roll on wheels, which are very effective on the smooth surfaces used for typical robot combat competition. Other propulsion strategies do pop-up with some frequency.

    • Tank Treads – Numerous combat robots have used treads or belts in place of wheels in an attempt to gain additional traction. Treads are generally heavier and more vulnerable to damage than a wheeled system and offer no particular traction advantage on the types of surfaces common in robot combat. Most uses of treads are for their striking appearance. The RobotWars competitors Son of Whyachi used a controversial cam-driven “Shufflebot” propulsion system, which was promptly declared ineligible for additional weight allowance at subsequent competitions.^[14]
    • Suction Fan – Several competitors experimented with the use of fans to evacuate air from a low-clearance shell to suck the robot down onto the arena surface and add traction. Robotica competitor Armorgeddon used a suction fan to increase traction and pushing power, and Robot Wars UK robot TerrorHurtz used a suction fan to counter the forces from its hammer/axe weapon. Similar designs have appeared in robot-sumo competitions where traction is a key factor.^[15]
    • Magnet Wheels – Another approach to gaining traction and stability involves the use of ring-shaped rare-earth magnets as wheels. This is, naturally, only effective in arenas which have magnetic metal surfaces. Due to the expense of large ring magnets, this trick has been used almost exclusively in three-pound and under “insect class” robots, although a lightweight battlebot General Gau tried implementing them. Heavyweight Robotica competitor Hot Wheels attempted to use a large chassis-mounted magnet to gain traction and apparent weight, and Beta Hurtz unsuccessfully attempted to use an electromagnet to counter the reaction forces of its massive hammer weapon at the BattleBots competition. The result ended in the robot being completely stuck to the floor.
    • Mecanum Wheels – The previously mentioned RFL super-heavyweight competitor Alcoholic Stepfather uses Mecanum wheels and specialized motor control systems that allow it controlled motion in any direction without turning. This is eerie to watch, and disruptive of attack and defense maneuvers by opponents. Root Canal implemented a similar design at BattleBots using Omni wheels angled at 45 degrees.
    • Translational Drift - Also known as Melty Brain or Tornado Drive, this sophisticated system supplements the thwackbot drivetrain with electronic rotation sensors and rapid speed controller switching that allows a rotating thwackbot to move in a controlled manner while spinning. Several robots have implemented this complex design, but none with particular success. Herr Gepoünden, a lightweight robot, has shown successful use of the Tornado Drive and has used it successfully in smaller competitions. The drive is implemented with an LED light system that tells the driver its current position, indicating where the robot should be driven to.
    • Flying – The 1995 US Robot Wars event had a flying competitor: S.P.S. #2 was a lighter-than-air craft buoyed by three weather balloons and propelled by small electric fans. It attempted to drop a net on the opponent. Nearly invulnerable to attack, it won the first match against Orb of Doom (see reference below), but ventured too close to the arena floor in the second match and was dragged down and "popped".
    • Rolling Sphere – The afore-mentioned Orb of Doom was a featherweight competitor at the 1995 US Robot Wars. It consisted of a remote-controlled toy car inside a hollow papier-mâché sphere. It was able to roll around the arena in a controlled manner, but was incapable of effective offense. A similar robot named Psychosprout appeared in the UK Robot Wars.
    • Rolling Tube -Snake competed at Battlebots and the US Robot Wars using a series of actuators to bend its triangular cross-section tubular body to roll, writhe, and slither across the arena.
    • Shuffling - refers to the movement of robots that are propelled by a cam-driven system. See Walking

    See also

    Robotics portal

    • Robot Fighting League (United States & Canada)
    • Robot Wars
    • BattleBots
    • Robotica
    • RoboGames
    • I, (Annoyed Grunt)-Bot - episode of The Simpsons featuring robot combat.
    • Model Warship Combat - robotic model warship engage in model combat using pneumatic cannons
    • Robot Arena 2 - Notable robot combat game

    References

    1. ^ History of Robot Battles
    2. ^ Robot Wars
    3. ^ "Hundreds gather for RobOlympics". USA Today. Archived from the original on 2004-03-22. http://robogames.net/news.php#106. Retrieved 2011-09-30. 
    4. ^ Silber, Kenneth. "From Robot Olympiads to the World Year of Physics". Tech central station. Archived from the original on 2004-12-30. http://robogames.net/news.php#219. Retrieved 2011-09-30. 
    5. ^ RFL Robot Combat Ruleset
    6. ^ Robot Fighting League - About Us
    7. ^ RobotCombat.com Robot Combat History - San Francisco 2001
    8. ^ 2001 Robotica ruleset
    9. ^ 1997 Robot Wars ruleset
    10. ^ 2001 Robotica ruleset
    11. ^ Team Juggerbot News Updates
    12. ^ http://www.botleague.net/doc/rfl-match-rules-0-03.pdf
    13. ^ 1999 BattleBots ruleset
    14. ^ Season 4 BattleBots ruleset
    15. ^ RobotSumo.com

    External links

    North America

    • Robot Fighting League - north and south american rules and oversight organization.

    South America

    • Brazilian Robot Combat League

    Europe

    • Fighting Robot Association - FRA

    Australia

    • Robowars Australia - National forum and Victorian organisation.