Useful Notes / Robot Combat

Last Rites (left) and VD6 (right) settling their differences over a nice cup of tea.

"Combat robots is just fun. It represents so many different things mixed together. The competition, the amazing people, the awesome robots, and the community that has surrounded NHRL is just amazing."

— Tommy Wong, creator of Droopy^note , a dual horizontal spinner which won the 3lb May 2023 championship, for the Norwalk Havoc Robot League

In 1993, a Lucasfilm toy designer named Marc Thorpe was disassembling a remote control vacuum cleaner he had pitched to his bosses. However, an idea soon came to him. What if he attached a chainsaw or a power drill to it? Marc had a vision of his creation cutting a hole through his wall. If other people built machines like his and fought each other, what could come of it? The following year, the first annual Robot Wars event took place, and as result, the sport of Robot Combat was born.

Robot Combat is a popular hobby/sport wherein competitors construct remote controlled machines (dubbed robots, although the majority are not autonomous) of varying designs to fight one another... to the DEATH! (Or a judge's decision, Ring Out, disqualification, and so on.)

Robot Combat first attained mainstream popularity in the late 90s and early 2000s, where BattleBots and Robot Wars enjoyed good ratings and were heavily advertised. From there, the number of competitions has skyrocketed to dozens per year across several countries and continents, most notably in Europe and North and South America. Robo Games still draws good crowds, and Battlebots still hosts non-televised tournaments from time to time, having spent more effort re-purposing their business as an educational robotics experience under the name Battlebots IQ. Builders come from all walks of life, from special effects technicians to programmers and engineering students from nearby schools, to your everyday hobbyist with access to a machine shop. As a result of the sustained interest in the sport, from 2015 on there was a revival of interest in televised competitions, with first BattleBots and then Robot Wars returning to the airwaves for (at present) four revival series of the former and three of the latter before it was cancelled again, as well as new series such as King of Bots coming out of China.

For a great source on learning the basics of robot construction, see here. For a great source on buying robot parts, see here.

Robot design is heavily varied in regards to mobility and weapons systems.

Mobility

• Wheeled Robots: The most common type of movement for robots; the number of wheels as well as the design of steering dicates how well a robot can be controlled. For example, two wheeled robots can spin faster on an axis, making them good designs for robots with spinning weapons (such as bars and discs), or for spinning a fixed weapon (such as the design for a thwackbot/overhead reaction robot). Robots which operate on car style steering lack the precision of zero radius turning, but make up for it through being in constant movement and also being easier to maneuver.
• Treaded Robots: Opting for tank treads instead of wheels, the design for treaded robots are useful in that they can climb over pretty much anything in their path, but are ultimately more form over function. They look great, but are also more complex to build, more easily damaged, heavier, and don't offer any real benefit in regards to traction.
• Walking Robots: This is where it gets complicated. Legitimate walking robots, that is, robots which move on independent legs, are a rare breed, costly to build, and while photogenic and crowd-pleasing, not very effective in battle due to a lack of speed. By legitimate, it is referring to the presence of shufflebots, which operate in a manner like walkers, but instead of using legs, use sections of feet in order to move faster while still benefiting from the weight advantage bonus that walkers receive (extra weight = extra weapons + harder to push around). Newer regulations disqualify shufflebots from getting this bonus, but have also made the qualifications for a "real" walker more stringent. Walkers are now mostly found in other robotics competitions, such as the non combat events of RoboGames.
• Flying Robots: Starting in the 2015 ABC reboot of BattleBots, flying robots have since been permitted to enter, where they are known as "drones." Every instance so far uses helicopter blades to keep them aloft. These were quickly found to be Awesome, but Impractical, since flying robots are severely affected by air currents within the arena, them being out of reach means their weapons are also out of reach, and should an opponent actually reach them, the fragility of their propellers means they are easily destroyed via a One-Hit Kill. In addition, flying robots are restricted only to weapons with very low kinetic energy, as Newton's Third Law will send them careening out of control otherwise. The most notable flying robot is Warrior Dragon, which competed in BattleBots 2016 and was defeated in one hit via HyperShock using a rake HyperShock's team bought at a nearby gardening store. From there on out, flying robots became increasingly rare, with Spitfire being the competition's only one left as of 2019.

Weaponry

• 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 La Machine was an early and effective wedge design as was Robot Wars Series 1 champion, Roadblock. This simple design is the secret to the success of Original Sin, an 8-time champion—and counting, as it's still active to this day—across RoboGames and ComBots, earning it the title of "World's Deadliest Wedge."
• 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 Hazard was a horizontal bar spinner, as were BattleBots 2016 champion Tombstone and Robot Wars Series 9 champion Carbide.
• Full Body Spinner: Taking the concept of the spinner to the extreme, a full body spinner (AKA shell spinner or tuna can spinner) rotates the entire outer shell of the robot as a stored energy weapon. Other robot components (batteries, weapon motor casing) may be attached to the shell to increase the spinning mass while keeping the mass of the drive train to a minimum. An FBS robot takes several seconds to spin the heavy shell up to effective speed, and they must evade their opponent while waiting for that speed. However, full body spinners can be a double-edged sword (or shield in this case), as they output so much centrifugal energy that they can be a hazard to even themselves, often leading to their spinners breaking from the recoil of impacts. As a result, most of the strategies against FBS robots boils down to tanking hits until their spinner breaks and then going in for the kill, and even those that do win matches often don't escape with fully-functioning spinners. The arena walls also present a hazard to these robots as they can ricochet off them uncontrollably across the arena, so drivers must be very mindful of their surroundings as well. The 1995 US Robot Wars heavyweight co-champion Blendo was the first effective full body spinner.^note The co-champion status comes from it being removed from competition because it was not just destroying its opponents, it was sending shrapnel over the barriers and into the audience., as was two-time BattleBots lightweight champion Ziggo, whose spinning shell was actually a wok. Robot Wars Series 7 champion Typhoon II was also one. The Robotic Death Company (Robotic Destruction Company in China) specializes in this type of robot; their greatest success with a FBS is Megabyte's 3rd-place finish at King of Bots in 2018.
• 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 BattleBots and Nuts 2 in Robot Wars. The oldest combat robot still competing, Herr Gepoünden from 2002, is a thwackbot.
• 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. This type of robot was popularized and standardized via The Master in BattleBots, which proved slippery and difficult to fight. BattleBots 2.0 middleweight champion Spaz was a torque reaction pickaxe robot. Robot Wars Series 8 finalist Gabriel was also one, though it could also swing its blade and move independently if needed. BattleBots Season 12 rookie Starchild provides a possible evolution with a vertical spinner as the "tail", though driving and landing hits with the added inertia proved difficult.
• Lifter: Using tactics similar to a wedge, the lifter uses a powered arm, prow, or platform to get underneath the opponent and lift it away from the arena surface to remove its maneuverability. The lifter may then push the other robot toward arena hazards or attempt to toss the opponent onto its back. The lifter is typically powered by either an electric or pneumatic actuator. Two-time US Robot wars and four-time BattleBots heavyweight champion Biohazard was an electric lifter, as was Robot Wars Series 2 champion Panic Attack.
• Flipper: Although mechanically resembling a lifter, the flipper uses much higher levels of pneumatic power to fire the lifting arm or ramp explosively upward. An effective flipper can throw opponents end-over-end through the air causing damage from the landing impact or, at Robot Wars, toss it completely out of the arena. Flippers use a large volume of compressed gas and may have a limited number of effective attacks before their supply runs low. Flippers can be either rear-hinged (lifting the opponent up directly) or front-hinged (aiming to get under the opponent then tip them over). Flippers have two weaknesses. The first is limited energy storage: Flippers typically have less than 20 attempts before they run out; Bronco and Apollo, among the most powerful flippers in BattleBots and Robot Wars, respectively, have only a little over a dozen flips per full charge. The other weakness is that a missed flip will send the flipper itself flying, during which it's at the complete mercy of its opponent. The two-time Robot Wars champion Chaos 2 and BattleBots super heavyweight champion Toro were flippers. Another notable robot with a flipper, Cassius, is responsible for popularizing the idea of the srimec (self-righting mechanism), as its flipper could also be used to turn itself back over after being flipped itself by other robots. Hydra, in BattleBots 2019, is also notable for being the first effective hydraulic-powered flipper, a subclass that, for a long time, had problems with speed and power.
• Clamper: Another lifter variant, the clamper adds an arm or claw that descends from above to secure the opposing robot in place on a lifting platform. The entire assembly then lifts and carries the opponent wherever the operator pleases. Two-time BattleBots super heavyweight champion Diesector was an electric clamper, as was 2003 finalist Complete Control.
• Dustpan: An uncommon variant on the clamper, the dustpan simplifies the design by replacing the lifting platform with a wide box open at the front and top. An opponent maneuvered into the box may then be restrained with an arm or claw from above. Some designs use only the box with no restraining claw. This design was popularized with S.O.B., which reached the middleweight finals of BattleBots in 2004; its Spiritual Successor is the heavyweight robot SawBlaze, which, while it has never won an event, has advanced very far every time.
• Vertical Crusher: Related to the dustpan, the vertical crusher uses a hydraulic cylinder attached to a sharp piercing arm to catch the opponent on a front wedge then pin and slowly penetrate the usually weak top armor. Enormous strength and careful engineering are required to build an effective crusher, which may be why there have been only two successful vertical crushing combat robots: two-time Robot Wars world champion and Series 5 champion Razer, and inaugural King of Bots champion Spectre.
• Horizontal Crusher: Similar to the vertical crusher in spirit but completely different in function, the horizontal crusher uses a pair of linked hydraulic claws to grab an opponent between them. They can be used as pure control bots to drag an opponent around without piercing their armour, or can use sharpened claws to crush the armour, but the latter design is prone to getting the claws embedded in an opponent. Even more difficult to engineer than a vertical crusher and far more difficult to drive, there have only ever been two successful horizontal crushers: two-time Robot Wars Annihilator champion Kan-Opener, and Robot Wars semifinalists Tough As Nails.
• 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 Killerhurtz were armed with an overhead axe.
• Flamethrower: THE Awesome, but Impractical weapon. Flamethrower robots are a cool concept on paper, but in practice, they usually operate ineffectively because the flames don't deal direct damage, and instead, must rely on their heat to hopefully fry the opponent's internal components from the inside. Since most robots are designed with armor and insulation to either absorb or redirect the heat from the core mechanics, this can automatically render the flamethrower moot, so robots with flamethrowers as their primary weapons are very rare. Instead, flamethrowers are often used as a secondary weapon to rack up damage points via Cherry Tapping for the judge's decision, should they fail to KO the opponent before the timer runs out. Some of the more notable competitors that utilize flamethrowers include BattleBots' SawBlaze, Blacksmith, and Gruff; and Crash 'n' Burn in RoboGames. The aforementioned Complete Control is one of the few robots able to use a flamethrower to great effect; as a clamper, it held its foe immobile over itself, upon which it proceeded to fry its opponents for the full 30 seconds it was allowed to.
• Exotic Weapons or Unique Weapons: Every now and then, someone comes in with a weapon never seen before. Most of the time, they're unsuccessful, but every now and then, they achieve success. Most of the weapon types seen above were once exotic weapons when new. Examples of robots with exotic weapons include Black Ice and Neptune, both of whom competed in BattleBots with harpoon-like tethers; Double Jeopardy in BattleBots, which uses a cannon with steel slugs making it the first Long-Range Fighter in any robot combat event; and Barbar-Ous in Robot Wars, which combines the Drum Spinner and Full Body Spinner by rapidly spinning its entire cylindrical body, a concept later used for Axe Backwards. The most successful exotic robot is Tentoumushi, which competed in both BattleBots and Robot Wars and advanced deep into both of them but has never actually won. Tentoumushi is a "Smother-Bot," using a large shell it holds in front of itself to completely smother the opposing bot in and restrict its movements while dragging the opponent wherever it pleases.
• Multi-Bot or Cluster-Bot: Not a weapon class but is so functionally different from anything else that it's often grouped in other lists of weapons, the multi-bot, sometimes known as a cluster-bot, is a group of two or more robots that function in the competition as a team. This is allowed as long as the total weight of all of the robots don't exceed the maximum for the weight class it's entered into. These robots fall into two groups: symmetrical and asymmetrical. Symmetrical multi-bots have each robot roughly the same in size and weight (and usually weapons), while asymmetrical ones have each unit with vastly different sizes, weights, and weapons. Symmetrical multi-bots have the advantages of being able to easily flank opponents and perform maneuvers single robots cannot, but because they are half the weight or less of single robots, they are fragile, easily tossed around and damaged, so they can succeed only through relentless attacking, not letting their opponents get a chance. Asymmetrical multi-bots have the main unit with the force and weight needed to tank hits but can't do the flanking symmetrical ones can. Both types require extremely good teamwork among its operators to function well. Notable examples of symmetrical multi-bots include the aforementioned Crash 'n' Burn, who made it to the semifinals in RoboGames taking out the aforementioned Tombstone and Megabyte along the way; as well as Robot Wars finalists √3 and Typhoon Twins and King of Bots semifinalist Thunder and Lightning. Notable examples of asymmetrical multi-bots include BattleBots finalist Witch Doctor, which is accompanied by a tiny robot named Shaman (though Shaman was retired by the time Witch Doctor reached the finals); and fellow BattleBots finalist Bombshell, accompanied by a light drone named Short Fuse.^note You may notice many of them advance extremely far but never seem to win. Robot Wars engineer Ian Watts specializes in this type of robot.

Shows based on the sport include:

• Robot Wars (1994–1997): The Trope Codifier (not the Ur-Example though) of the sport and not to be confused with the later BBC show. Created by Marc Thorpe as mentioned above and included many competitors that would later form/compete in BattleBots or become famous through other means (such as James Hyneman of Mythbusters fame and Will Wright, creator of SimCity). Lasted 4 seasons.
• Robot Wars (1998–2003, 2016–2018): The show that most people associate the sport with, the first of the "big three" and the longest lasting with 7 conventional and 2 "Extreme" seasons and several international spin-offs. Was later revived in 2016 for 3 more series before being cancelled again.
  • Techno Games (2000–2003): A sister show to Robot Wars that focused on the non-violent aspect of the sport as a form of robot Olympics, featuring a variety of sports-themed events such as the long jump, shot putt and robot soccer, with machines usually custom-built for each event. Several of the events were similar to the old Robot Wars trials, many of the teams were also competitors in said show, often with the same robot with a new name and paintjob, and the shows also shared a lot of the same crew. Four seasons.
• BattleBots (1999/2000–2002; 2015–2016/2018–present): The second of the big three and created by former Robot Wars competitors. Had a much more "laid back" attitude than its UK counterpart akin to boxing and many Robot Wars teams also competed on this show with either the same (Killerhurtz team) or a completely different (Razer team) machine. Lasted five official and two "prototype" seasons. Was revived thirteen years later with a more serious (but still light-hearted) focus on robot fighting.
• Robotica (2001–2002): The last of the big three and with a format closely resembling Robot Wars before its Retool. Lasted three seasons.
• King of Bots (2018–present): A new series originating from China, initially in the style and format of BattleBots with the following seasons adopting a format closer to that of its spin-off. While it currently has no English language version, it still drew a lot of international competitors to take part in its debut series and subsequently managed to gain a lot of attention and acclaim even from Western viewers who don't understand a word of Chinese.
  • This Is Fighting Robots (2018–present) A Youku^note chinese streaming site exclusive spinoff from King Of Bots where several celebrities teamed up with robots builders and competed.
• BashBots (2019–present): A online series made in Garry's Mod, which uses the format from BattleBots but adds some arena elements from Robot Wars like a floor flipper and a pit.

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