Thwackbots

Spin Doctor, the thwackbot, obliterated Matilda's tusks

Thwackbot is the term for any robot that is designed to attack by spinning in place, striking a heavy blow to an opponent's side, should it come within range. This type of design was popular in Robot Wars, but was not considered to be an active weapon. As such, thwackbots were not allowed to participate in Series 7 after a requirement for all robots to have active weapons was instated. Thwackbots can be divided into two basic categories; Sit-and-Spins and Torque Reactions.

Sit-and-Spins

A Sit-and-Spin refers to any robot whose only means of attack is to spin on its own axis. Most sit-and-spin robots consisted of an arm with a sharp or blunt weapon on the end, but others featured a round body with spikes or blades around the sides. Sit-and-spins seem like a desirable kind of weapon because they work under the same principle as a Full Body Spinner- a heavy spinning object that makes contact over a small surface area- in theory a sit-and-spin would be just as powerful.

However in practice, there are several pitfalls of this design. While it is potent, a sit-and-spin cannot move and attack at the same time; to attack it must spin on the spot. Spinning in place is not considered to be agressive behavior, a fact that the judges will note if a match winner is to be chosen based on points. In addition, if its wheel or drive becomes damaged, not only will its locomotion be crippled, but its weapon will too, since a Sit-and-Spin uses its drive system to attack.

Sit and spins waned in popularity as more advanced weapons took to the stage. Recently though, a builder in the US discovered a way to allow Sit-and-Spins to move and spin at the same time. Dubbed "Meltybrain" technology, it involves equipping a Sit-and-Spin robot with LED's and a detection system, allowing it to automatically figure out its position at any given moment.

Dutch Wars runner-up Lizzard used a whip-like tail in place of a rigid arm.

List of Sit-and-Spin Robots

Robots are listed alphabetically. Robots that aren't heavyweight are listed with a green background.

Robot	Series Appearances as Sit-and-Spins	Notes
Abaddon	Series 3	Whipping tail
Brawler	US Season 2
Crasha Gnasha	Series 3	Whipping tail
IDO	Dutch Series 2
Impact	Dutch Series 2	The hammer was covered in fur that was often set alight.
Lizzard	Dutch Series 1-2	Whipping tail
Spin Doctor	Series 2	First Sit-and-Spin design. Managed to rip off one of Matilda's tusks
Stomp	Series 3	Walking robot, used its large box legs as weapons when spinning.
T-Wrecks	Series 7	Qualified for Series 7 despite not having an active wapon.
Wizard	Series 2

Torque Reaction

Torque Reaction is the term used to describe the subcatergory of thwackbots that use their wheel axles to swing a weapon overhead. This is done by attaching an arm, similar to that of a Sit-and-Spin, directly to the wheel axle of the robot. All known robots with torque reaction weapons are axlebots (although not all axlebots have torque reaction weaponry). This setup causes the arm to swing overhead whenever the robot reverses its motors. The design is renowned for the advantages it offers against several conventional types of weapons. Robots with torque reaction weaponry are always invertible, so Lifting Weapons do not affect them. They have virtually no flat sides, making it difficult for Overhead Weapons to hit them. And they are not as boxy as other types of robots, making it difficult for Gripping Weapons to get ahold of them.

However, these advantages come at a price. Torque Reaction axlebots are very difficult to control, as was evidenced by Stinger in its debut appearance. The weapon must be swung at a very high velocity in order to cause damage. Worst of all, the design requires the wheels to be exposed; any protection detracts from the power of the weapon.

Stinger, the most successful robot to feature a torque reaction weapon

List of robots with Torque Reaction weapons

Robots are listed alphabetically. Robots that aren't heavyweight are listed with a green background.

Robot	Series Appearances with Torque Reaction weapons	Notes
Armour Geddon	Series 3
Attila the Drum	Series 4
Flip Flop Fly	Series 3
Infernal Contraption	Series 6-7, Extreme 2	Armed with a spinning drum
Slamtilt	Dutch Series 2
Stinger	UK Series 3-6, Extreme 1-2, US Season 1	First torque reaction weapon (along with Weeliwako) and the most successful. Featured a pizza cutter in Series 3 and a spiked mace in all subsequent appearances.
The Mangulator	Series 4
Weeliwako	Series 3	Along with Stinger, the first torque reaction weapon to appear in Robot Wars.