Cutting discs

Cutting discs
Roadblock cuts into King Buxton's wheels
Weapon Category	Rotating weapons
Robots
Pioneer(s)	Satoru Special, The Master, TMZ (1994 US competition) Dead Metal, Roadblock, Sergeant Bash (televised series)
Notable Robots	Agamemnon, Alexander, Attiller (the Hun), Vicious-1 (1994-1997 US competitions) Beast of Bodmin, King Buxton, Pussycat, Wild Thing (televised series)

Cutting discs were a type of small rotating weapon prevalent in earlier Robot Wars competitions, including the original 1994-1997 US events. As their names suggest, they are specialised in cutting, grinding or tearing into opposing robots. A wide variety of discs were used, ranging from off-the-shelf circular saws to custom-made blades.

The very first combat robots to utilise a cutting disc included Satoru Special, The Master and TMZ, all debuting in the inaugural 1994 competition. The Master itself would become one of the most influential and successful heavyweights in the pre-television era, using its cut-off blades to become the co-champion of the 1995 US Heavyweight Face-Off.

Cutting discs were also introduced in televised Robot Wars from the first UK series; champion Roadblock was armed with a petrol-powered circular saw as its secondary weapon, as were House Robots Dead Metal and Sergeant Bash. Other competitors from Series 1 with these weapons included Scrapper, Plunderbird 1 and Uglybot, with many more emerging throughout the earlier series. Dead Metal would ultimately maintain the use of circular saws in later incarnations; the Series 3-7 and Series 8-10 builds incorporated a larger-diameter disc for extra damage. Meanwhile, the weapon type saw further success with competitors such as Pussycat, which finished runner-up in The Fourth Wars and won multiple side competitions with custom-machined blades.

Definition

Pussycat's twin blades as used in Series 7

A cutting disc (also referred to in televised series as a cutting blade or angle grinder) is a generally small, thin disc weapon designed to spin and cut into other robots, or grind at their surface. Their primary purpose is to cut, shred and slice through other robots, unlike heavier and thicker spinners which aim to gouge, tear and concuss. As well as slicing through a variety of armour materials - including metal, wood and plastic - they could also be used to damage wheels/tracks, aerials, batteries and other sensitive components. To this extent, they were capable of causing severe or terminal damage in earlier events.

Cutting discs are usually comprised of two distinct sub-types:

• Off-the-shelf circular saws, cutters, cut-off blades, friction saws and grinding discs. Abrasive and diamond-edged discs were among the commonly-used variations permitted under the Robot Wars rules.
• Custom-made cutting discs optimised for greater damage output, like the blades of Pussycat.

Over the course of the televised show's history, typical circular saws saw less frequent use, with many off-the-shelf discs shearing upon impact like the often-broken rear saw of Sergeant Bash, or Pussycat's interchangeable carbide-tipped blade which caused the latter to be disqualified from Series 3. The custom-designed cutting disc saw more use throughout later periods of the show's original run, but both weapon types proved very sparsely-used in the reboot, with modern armour often totally resisting the effect of cutting discs.

Most cutting discs were small in size, although some competitors used larger-diameter discs throughout both of the show's runs. These discs, such as those equipped on the original version of Ming and the Series 8 version of The General, were closer to horizontal or vertical spinners in size, but featured more teeth or pointed edges along their circumference than a typical flywheel and retained the low thickness of a cutting disc.

Cutting weapons could easily be mounted on a moveable arm, enabling them to be brought down from overhead to improve the weapon's effectiveness or allow for a potential synergy with other weapons, such as Dead Metal clamping competitors in its claws before moving its circular saw directly into the trapped robot. Competitors such as Tentoumushi and Haardvark would use similar moving discs, with or without secondary weapons.

Advantages and Disadvantages

Advantages

Dead Metal sends sparks flying while slicing through Aggrobot

Pussycat's blade enabled it to cause significant damage throughout its Series 4 run, notably to Razer's internals, armour and wheels in its Heat Final

The weight and small size of King B Powerworks' cutting disc allowed its team to equip the disc without compromising on the robot's lifting forks or drive system

• As with other spinning weapons, cutting discs proved effective in causing damage to not only most kinds of armour - particularly in earlier series - but also wheels, wheelguards or other exposed components. Pussycat's Series 4 run best demonstrated this - not only was it able to cause extensive damage to the armour of Robochicken, Thermidor 2, Dominator 2 and Chaos 2 at various points during this series, but also sever Reptirron's fuel lines and damage the wheels/wheelguards of Razer and Hypno-Disc respectively.
  • In rare cases, they could also cause major internal damage to opponents. Notably, in Pussycat's Series 4 Heat Final, the vibrations caused by one of its early hits on Razer resulted in the latter's cut-off switch failing, and the third seed to be eliminated after getting stuck against the wall in forward drive.
• Different types of cutting discs can be swapped out and used as interchangeable weapons to suit certain types of opponents. Alan Gribble explained in an Ultimate Real Robots magazine article that the early Extreme 1 incarnation of Pussycat was originally intended to use both two and four-pointed blades; the latter for battles where it could launch repeated attacks and score high damage points against robots with tougher armour.
• Cutting discs could be easily integrated into an invertible design, as Pussycat, 3 Stegs 2 Heaven and the Series 3-5 and 7 versions of King Buxton demonstrated.
• Compared to heavier spinning weapons, cutting discs are generally less affected by recoil, making them potentially more reliable at operating for full matches.
• The lightweight nature of a cutting disc meant that any spare weight left over for the wielding robot could be used to incorporate additional weapons (e.g. a second cutting disc), tougher armour or more powerful drive systems. The cutting discs formerly used by King Buxton, for example, were added in such a way that they increased the robot's damage potential without compromising on the robot's armour, motors or primary lifting weapon.
• Off-the-shelf circular saws and angle grinders provided a very inexpensive way to weaponise a robot in the earlier series of the show.

Disadvantages

Pussycat's cutting blade could only cause superficial damage to M2 in Series 7, resulting in it losing the Judges' decision

3 Stegs 2 Heaven gets its disc tangled in Eleven's hydraulic cables

Shredder's cutting disc is overpowered by S3's vertical spinner

• Especially in later series, cutting discs very often struggled to damage tough armour, which put robots with them at a significant disadvantage on Judges' decisions. Pussycat's loss against M2 in Series 7 demonstrates this, as its blade could only cause superficial scratches to M2's armour at best. In the reboot era where HARDOX armour was commonplace and almost completely resistant to cutting discs, only a limited number of competitors implemented cutting discs into their design, and only in Series 8.
• Many cutting discs require sustained contact to output their full damage potential, contact which is often hard to maintain in the arena. When faced with tough armour, cutting discs may also stop or jam upon contact if they cannot cut through.
  • Wild Thing demonstrated a rare example where a cutting disc could not break free from its opponent after cutting through its armour, becoming locked together with Vader after its cutting disc could not break free.
  • Conversely, Wild Thing was able to convert this weakness to its advantage in the above scenario. By embedding its disc into Vader's armour, it could use the weapon to keep its opponent hooked while pushing it into arena hazards and House Robots. Pussycat also demonstrated this characteristic in its Series 4 Semi-Final clash against Dominator 2, dragging the latter back in the closing moments after slicing into its nitride-coated titanium shell.
• Cutting discs are particularly prone to entanglement devices (intended or otherwise) and other exposed components, such as when 3 Stegs 2 Heaven's disc was entangled by the cables of Eleven, or when Pussycat's blade was totally stopped by the fur of Diotoir.
• Being lightweight in nature, cutting discs are generally overpowered by heavier spinners, such as when S3 ripped an entire cutting disc from Shredder with a single blow, or when Fluffy ripped away the blade of Pussycat.

List of Robots with Cutting Discs

Robots are listed in alphabetical order.

DESKTOP MODE ONLY: Robots which are not heavyweight entries are listed with a green background. House Robots are listed with a gold background. Robots from the 1994-1997 US competitions are listed with a purple background.

Robot	Series Appearances with Cutting Discs	Notes	Image
3 Stegs 2 Heaven	Series 5	Was a spinning blade in Extreme 1, replaced with a toothed disc for Series 5.
Abaddon	Series 3
Agamemnon	1996 US Championship	1996 Middleweight Face-Off and Melee Champion. Twin steel cutting discs powered by a 2hp engine attached to the end of a 'shock-loaded' arm. Whole weapon assembly could be removed to allow Agamemnon to function as a simple rammer.
Angel of Death	Series 2	Two cutting discs with estimated top speeds between 10,000rpm and 15,000rpm.
Atlas	Series 3
Attiller (the Hun)	1996 US Championship	1996 Lightweight Face-Off Champion. Used a row of four IC-powered rotary blades with teeth bent inwards or outwards, referred to as a 'soil tiller' weapon. Designed primarily to lift, deflect and potentially turn opponents over rather than inflict damage.
Bad Monkey	1997 US Championship	Featherweight. Two of the robot's interchangeable rotating weapons were cutting discs; an 'abrasive saw' and a 'jagged' metal blade.
Beast of Bodmin	Series 3	Series 3 Semi-Finalist and successor to Roadblock.
Bernard	Extreme 2, Series 7	Small cutting blade mounted high up the robot's wedge.
Black Widow	US Season 2	US Season 2 Tag Team Terror co-champion, partnered with Rocky-Bot-Boa.
Bodyhammer	Series 2	Front-mounted 6-inch saw, equipped in tandem with a reciprocating spike.
Bot Will Eat Itself	1997 US Championship	Featherweight. Paired one of the cutting discs inherited from Rampage (see below) with another modified to wield chainsaw chain flails.
Brutus Maximus	Series 6-7	Set of three rear cutting discs connected on one axis.
Bulldog Breed	Series 3	Used twin cutting discs before opting for a flipper in future appearances.
Buzzant	Extreme 2	Vertically mounted buzz saw.
Buzzcut	1997 US Championship	Featherweight walker; one of the first two robots built by Christian Carlberg. Banks of four cutting saws mounted to each end, all powered by a 1.5hp weedeater motor.
Cataclysmic Variabot	Extreme 1-2	Later known as CV. Used interchangeable weapons, but only equipped the axe in its televised fights.
Cerberus	Series 3	Tungsten-tipped circular saw-like disc. Had to be removed before entering the arena due to hardened steel blades being prohibited.
Challenger	Series 2-3	Used a rear angle grinder in Series 2, and front-mounted rotating blades in Series 3 as Challenger 2.
Colossus	Series 6-7	Main weapon was a rear-hinged flipper.
Crasha Gnasha	Series 3	Cutting saw came from the Swedish Air Force.
Cruella	Series 2	Only used a circular saw in its second series.
Cyberknight	1995 US Championship	Horizontally-mounted saws, one placed beneath the chassis akin to a modern undercutter. Powered by an internal-combustion engine at the back of the robot.
Damacles	Series 2	Lightweight robot. Cutting disc mounted on a spring-loaded arm.
Darkness	US Season 2	Pair of cutting blades mounted horizontally.
Dawn Patrol	1995 US Championship	Middleweight. Three belt-driven steel discs arranged in a horizontal 'tri-delta' layout, powered by a 5hp Briggs & Stratton lawnmower engine.
Dead Metal	Series 1-10, Extreme 1-2, Dutch Series 1-2, German Series, US Seasons 1-2, Nickelodeon	House Robot. Upgraded in Series 2 with interchangeable 'Abrator' and diamond cutter discs; and again in Series 3 and Series 8. Mounted on a movable arm in Series 1-2, then a head assembly for Series 3 onwards. Series 3-7 weapon was a 96cc Stihl cut-off friction saw, while the Series 8-10 incarnation utilised a 450mm magnesium sawblade.
Demolition Demon	Series 2	Heat Finalist. Used new weaponry in Series 3 as Demolition Demon 2.
Diskotek	US Season 2, Nickelodeon	Borrows components and design aspects from Team Robot Dojo's Robotica champion Flexy Flyer.
Disruptor	Series 2	Mounted on a movable arm.
DooAll	1997 US Championship	Originally fought with a 4hp abrasive cutting disc, interchangeable with a diamond saw. Recurring damage to the weapon resulted in the whole assembly being replaced by a hinged 'snowplow' after second battle.
Eddy Evolution	Extreme 2	Featherweight. Small cutting blade at the front.
Elvis	Series 2	Disc was added for Elvis' second Robot Wars campaign.
Finagler	1997 US Championship	Lightweight. Small 'grinding wheel' was incorporated into the back of the robot.
Flensburger Power	Extreme 1	Invited to compete in Extreme 1, after its domestic German series did not proceed that year due to a lack of entrants.
Flextreme	Dutch Series 1
G.B.H.	Series 2	Two 7-inch and two 9-inch saw blades mounted at the rear, spinning at 6,000rpm. Series 2 Semi-Finalist in this form, although relied on its lifting scoop for victories.
Gator	1997 US Championship	Lightweight. 1997 incarnation featured a horizontal saw, powered by a high-torque DC setup with chain drive and a rotational speed of 2,300rpm.
Gigan	1995-1996 US Championships	Featherweight/super lightweight entry by Peter Abrahamson. Pair of cut-off saws interchangeable with a set of five-pointed flails.
Grinder	Series 3	Middleweight; named after its angle grinder weapon.
GroundHog	Series 2	Predecessor to Firestorm.
Gutrip	1996-1997 US Championship	Twin milling cutters powered by a large motor (a car starter motor in 1997). High torque output enabled the robot to snag and lift opponents as well as damage their undersides.
Haardvark	Series 3	Mounted on a movable 3-foot 'cutting arm'. Was meant to have a circular saw in Series 2, but this and its supporting arm had to be removed to remain within the weight limit. Interchangeable discs for Series 3 included a reinforced abrasive disc and a 12-inch diamond-edge saw, though the latter went unused.
Hard Cheese	Extreme 1	First official Middleweight Champion. Four-toothed cutting blade used only in Extreme, replacing a former hammer weapon.
Have a Nice Day	1995 US Championship	Middleweight. Full internal combustion power for both weapon and drive; engine had a tendency to 'suffocate' on its own fumes during battles.
Hercules	1997 US Championship	Pairs of 'synthetic diamond wheels' or metal cutters were among the robot's interchangeable spinners, which could be attached to the back of its lifting arm.	Hercules with its spiked lifter and twin cutting discs
Hippobotomus	Extreme 1, Series 5	Also known as Fighting Torque in Extreme 1.
Holobot	1995 US Championship	Super Lightweight (featherweight) entry from Robot Action League. Armed with saws on both ends; one vertically, one horizontally. 1995 Super Lightweight Face-Off Runner-Up.
Hyena	1997 US Championship	Middleweight. Set of three 'abrasive cutting saws' on a front axle powered by a drill motor.
King Buxton	Series 3-5, 7, Extreme 1	Disc was mounted at the rear. Spun at 3000rpm as King B3, and 8000rpm as King B Powerworks. King Buxton also competed in Series 2 and 8 without a cutting disc.
Kitty	Series 7, Extreme 2	Featherweight. Essentially a scaled down version of Pussycat, with its interchangeable discs including a circular saw and a four-toothed Pussycat-style blade.
Leighbot	Series 1	Rear angle grinder.
Limpet	Series 2	Front-mounted disc.
Lizzard	Dutch Series 2	Heat winner in this form, small front-mounted disc used in combination with a sit-and-spin design.
Mad Cow	US Season 1	Front wedge and rear cutting disc.
Malfunktion	Series 3	Robotic Soccer-only competitor.
Malice	Series 2	Reserve Robot.
Maximus	Extreme 2	Located in the centre of a front-hinged lifter. Claimed to spin at 18,000rpm.
Mighty Mouse	Series 7	Equipped with a pair of horizontal rear discs to comply with the active weapons rule, having previously just used a static swinging tail.
Milly-Ann Bug	Series 2	Replaced with static spikes following Series 2.
Ming	Series 3	Very large cutting disc mounted at an angled horizontal level.
Minimalistic	Extreme 2	Antweight.
Mouser	1997 US Championship	Lightweight. Abrasive cutting saws on the front and rear, driven by electric motors and protruding from the robot's dome-shaped shell.
Neoteric	Extreme 2	Featherweight from Team Roaming Robots. Sized closer to a vertical flywheel than a typical cutting disc.
Nezumi	1996 US Championship	Featherweight. Electric-powered saw placed near the top of the robot's carbon-fibre shell.
ORAC	Series 2	Mounted on an arm.
Panzer	Series 3, Extreme 1	Known as Panzer Wraith in Extreme.
Pathetica	Dutch Series 1	Primary weapon was an axe, with a rear-mounted vertical cutting disc.
Penetrator	Series 2	Armed with a retractable cutting disc and spikes.
Piranhabot	1995 US Championship	Super Lightweight (featherweight). Two sawblades attached to one axle, with a third located on a moving arm on the other side.
Plunderbird	Series 1, Series 3	Interchangeable with a retracting spike in Series 1 as Plunderbird 1. Unused in Series 3 as Plunderstorm.
Pretty Hate Machine	1997 US Championship	Lightweight walker based on a scaled-up version of Buzzcut's design. Armed with two banks of three cutting saws, each bank powered by its own 1.5hp weedeater motor. 1997 Lightweight Face-Off Quarter-Finalist and Lightweight Melee Finalist.
Prince of Darkness	Series 1	Rear-mounted saw used in the Gauntlet and Arena Semi-Final stages; not mentioned onscreen.
Prometheus (UK)	Series 2
Prometheus (US)	Series 3
Purple Predator	Series 3	Armed with a front-hinged flipper and rear-mounted disc.
Pussycat	Series 3-5, 7, Extreme 1-2, US Season 1	Most notable and successful robot armed with a cutting disc. Series 4 runners-up, as well as winning numerous side competitions in the UK and US versions. Variety of two (Extreme 1), four or eight-pointed (Series 7) custom-machined or water-cut blades mounted interchangeably, replacing conventional discs from Series 3.
Rampage (1996)	1996 US Championship	Featherweight. Used two Makita saws (each with a 3 3/8-inch diameter) powered by 14.4V Craftsman drill motors, each one mounted to a 'spring-loaded' arm at either end.
Rampage	Series 2	Rear-mounted horizontal disc.
Reptirron	Series 4, 6-7	Mounted on a hydraulic arm in Series 4, paired with a flipper in Series 6-7.
Roadblock	Series 1-2	First UK Champion. Use of its saw was limited, with Roadblock mainly relying on its wedge and pushing power.
Robochicken	Series 7	Rear disc described by the team as the "Rooster Rotavator", used in tandem with a flipper and axe.
Robot Redford Jr	1996 US Championship	A four-sided cutter was among the extra weapons added to the robot for the Heavyweight Melee event, mounted on the right-rear corner.	Robot Redford Jr with its extra weaponry, including four-sided cutter (left)
Ron	Series 2
Rosebud	Series 2	Lightweight Championship competitor.
Rosie the Riveter 2	US Season 2, Nickelodeon	US Season 2 Grand Finalist. Active weapon added after the original Rosie the Riveter used only static weaponry.
Rumble	Series 2	Rear-mounted.
Satoru Special	1994-1996 US Championships	The first three incarnations, including the original 1994 lightweight, had a small grinding disc attached to the end of an arm. In the case of the 1994 incarnation, the 'arm' comprised of a modified Makita drill. Satoru Special 3, entering the 1996 middleweight category, had the disc mounted to a curved pole and powered by a weedwhacker motor.
Saw Point	Series 7, Extreme 2	Had two angled discs running parallel to each other.
Scar	Series 4	Front cutting 'wheel' with up to six hardened steel 'cutters'; claimed to have three 'cutters' according to its statistics board.
Scorpion	Series 4	Featured two smaller cutting discs in addition to a larger spinning disc at the rear.
Scrapper	Series 1	A set of four vertical saw blades at the front, connected on the same axle, and two horizontal saw blades at the rear. The individual blades were 7-inches and 9-inches in diameter.
Scrappy	1996 US Championship	Middleweight. Had a rear cutting disc in addition to entangling nets.
Sergeant Bash	Series 1-2	House Robot. Removed after Series 2, and replaced with a decorative buckled saw.
Shapeshifter	Dutch Series 1	Used a lifting scoop in Dutch Series 2.
Shredder	Series 5-7	Two small, thin counter-rotating discs were located side-by-side in Series 5-6. Thicker discs were used by Shredder Evolution in Series 7.
Shuriken	US Season 1	Two horizontal discs, much like Shredder, which debuted in the same year.
Silver Box	US Season 1	Later fought under the new identity Zanzara.
Small Torque	Series 4	Spun at up to 4,000rpm. Designed to function as a third wheel, allowing the robot to run inverted at speeds of up to 20mph.
Stealth	Series 3	Armed with a flipper and large rear cutting disc.
Sub-Version	Series 7, Extreme 1	Known as Sub-Version 1.1 in Series 7.
Sumpthing	Series 5, Extreme 1	Used an axe weapon in place of the discs for Series 3-4 and 6.
Sweeney Todd	Series 8	Middleweight robot, but entered as a heavyweight. Two angle grinders mounted at both ends of the robot.
T-Bone	Series 5
Techno-Lease	Series 3	Added to a moving arm. First Dutch representative in Robot Wars.
Technophobic	Series 2
Tender Caress	Series 2
Tentoumushi	Series 3	Middleweight entry from US competitors Robot Action League. Electric 'grinder' mounted on an overhead linear-actuated arm, concealed within a 'smothering shell' made out of a ladybird sandpit. Used to damage robots trapped by the shell. Middleweight Melee Co-Champion and War of Independence Champion for this series.
Terror Australis	Series 3	Used a horizontal cutting disc on the original version, but not its Nemesis replacement.
Terror Turtle	Series 7-8	Used a horizontal spinning disc in Series 7-8. Instead used an overhead spinning bar in Extreme 2, and a conventional bar spinner in Series 10.
The Bishop	1997 US Championship	Middleweight. Originally armed with a two-stroke 'abrasive cutting wheel', which became damaged and was replaced by a diamond saw. Further damage sustained in the Middleweight Face-Off left The Bishop fighting in Melee events without a functioning weapon.
The Enforcer	1996 US Championship	Lightweight. Echo 7-inch steel cutting disc, powered by a weedwhacker motor and attached horizontally to the end of a chain-driven arm. Whole weapon was later replaced with an electric lifting arm due to reliability issues.
The General	Series 8	Dual cutting blades, taller than the robot itself, spinning at between 500 and 1,000rpm.
The Little Green	1997 US Championship	Featherweight. Small, electric-powered diamond saw.
The Master	1994-1996 US Championships, 1995 UK Open	1995 Heavyweight Face-Off Co-Champion. A '4hp circular saw' powered by an internal combustion engine, one of the robot's most frequently used 'modular' weapons. 1995-1996 iteration had the whole saw assembly - including engine - attached to the axle, enabling the weapon to also swing overhead. Could be mounted vertically or horizontally in 1995.
The Nexus 7	1995 US Championship	Super Lightweight (featherweight). Horizontally-mounted sawblade attached to the front.
The Piecemaker	Nickelodeon	Middleweight robot competing amongst heavyweights with two grinding discs
Thermador	Series 3	Rear-mounted disc and front-mounted horizontal claws.
The Termite	US Season 2
Thud	Series 2	Super Heavyweight Championship competitor.
Thwonkis Mobilis	1997 US Championship	Featherweight. Small 'cutting saw' at the front, powered by an electric motor.
TMZ	1994 US Championship	One of the robot's originally-planned interchangeable weapons was to be a 7-inch sawblade powered by a weedwhacker motor. The weapon mechanism was barred by event organisers due to concerns about the durability of its 3/8 inch-diameter shaft. Instead, the sawblade was attached horizontally to the chassis as a static weapon.
Uglybot	Series 1
Unibite	US Season 1	Very large horizontal disc with serrated teeth. Replaced with a conventional flywheel for US Season 2 when it competed as Unibite 2.0.
VIPER 01	Series 5
Velocirippa	Series 5, Extreme 1	Competed in Series 3, 4, Extreme 2 and 7 without a cutting disc.
Vicious-1	1997 US Championship	A pair of off-the-shelf angle grinders were modified into "milling saws" and attached vertically to the back of the robot. 1997 Middleweight Face-Off Champion.
W.A.S.P.	Series 6
Webster	1997 US Championship	Lightweight. Sets of small circular saws were added to the front and back during construction; one set was integrated into the robot's front wedge shape.
Wheelosaurus	Series 4	After first debuting in Series 2, Wheelosaurus used interchangeable cutting blades in Series 4.
Widow's Revenge	Series 5	Front-mounted cutting disc and rear mounted drum spinner.
Wild Thing	Series 6	Series 6 Semi-Finalist. Used a wedge and lifter in all other appearances, incorporating a horizontal flywheel in Series 5.
Xenomorph	Series 7
Zanzara	Nickelodeon	Repurposed from loanerbot Silver Box.
Ziggy	1997 US Championship	Lightweight entry rebuilt from the 1995-1996 featherweight of the same name. Large abrasive disc powered by a two-stroke internal combustion engine, taking up most of the robot's weight allowance. Prone to causing gyroscopic imbalance while running.