Editing Robot-sumo (section)

== Robot design ==
Standard sumo robots resemble car-like robots, consisting of a chassis with wheels, and usually equipped with sensors, when with some level of autonomy. The use of mechanisms that physically damage the opposing robot is not usually permitted. For majority of the classes, mainly Mega Sumo and Mini Sumo, a robot design project is usually divided in three disciplines: [[Mechanical engineering|Mechanics]], [[Electronics]], and [[Computer programming|Programming]].<ref name=":10">{{Cite web |title=How to Make a Sumo Robot, Sumo Robot Parts {{!}} JSumo |url=https://blog.jsumo.com/how-to-make-sumo-robot/ |access-date=2025-01-03 |website=blog.jsumo.com}}</ref> 

Competitors are encouraged to build their own robots, respecting each competition class' and security rules. In Sumo LEGO, in particular, only [[Lego]] pieces must be used to build the robot, mainly using [[Lego Mindstorms NXT|Mindstorms NXT]] or [[Lego Mindstorms EV3|Mindstorms EV3]] robotics kits.<ref name=":29">{{Cite web |title=ThundeRatz {{!}} Time LEGO |url=https://thunderatz.org/projects/robots/lego |access-date=2025-01-03 |website=thunderatz.org}}</ref><ref name=":11" /> 

A lot of projects employs electronics components and mechanical parts sold in robotics stores. With the popularization of standardized robot-sumo competitions worldwide, mainly Mega Sumo and Mini Sumo, specialized robot-sumo parts stores appeared, such as JSumo <ref>{{Cite web |title=JSumo Ultimate Robot Parts & Robot Kits Shop for Winners |url=https://www.jsumo.com/ |access-date=2025-01-03 |website=www.jsumo.com/ |language=en}}</ref> and Sumozade,<ref>{{Cite web |title=Sumozade Robotics {{!}} Robot Parts {{!}} Robot Kits {{!}} Robot Shop |url=https://www.sumozade.com/ |access-date=2025-01-03 |website=www.sumozade.com}}</ref> both based in [[Turkey]], which even sell complete Mega Sumo and Mini Sumo robot kits.<ref>{{Cite web |title=Robot Kit Prices {{!}} Mini Sumo Robot Kit {{!}} Sumo Robot Kits {{!}} JSumo |url=https://www.jsumo.com/robot-kits |access-date=2025-01-04 |website=www.jsumo.com/ |language=en}}</ref>

=== Mechanics ===
The [[Mechanical engineering|Mechanics]] consists in the infrastructure that supports and accommodates all the components and systems of the sumobot, including [[Engine|motors]], [[Wheel|wheels]], [[Printed circuit board|PCB]]'s, [[Sensor|sensors]], among others.

A standard sumo robot is wheeled driven robot with a locomotion system. The locomotion system usually consists of driving motors with a coupling system to the wheels, which usually employs a [[Reduction drive|reduction drive system]] to shift the output speed. [[Brushed DC electric motor|Brushed DC motors]] have been the most employed ones, <ref name=":10" /> but there are also robots with [[Brushless DC electric motor|brushless DC motors]].<ref name=":14" /> Motors from [[Maxon Group|Maxon]] or [[:de:Faulhaber_(Unternehmen)|Faulhaber]] brands have been popular choices among highest level competitors,<ref name=":10" /> such as robots in the All Japan Robot-Sumo Tournament.

Another commonly employed design for a sumo robot is an angled [[wedge]]/[[Inclined plane|ramp]] in the front of the body. This wedge is usually coupled with a [[blade]] with the purpose of invading the opponent from below and lifting it, so it becomes easier to push it out of the arena. <ref name=":10" />

For Mega Sumo robots, since magnets play an important role in the dynamics performance, the chassis are usually designed to support the desired number of magnets. A builder might choose between a heavier or a lighter robot based on the number of magnets allocated.<ref name=":9" /><ref name=":0" />

Some robot designs also employs peripheral mechanisms. Though classes have dimension limits, they are usually limited to the start of the fight, and once the fight starts, the robot is allowed to expand its size. <ref name=":4" /> Examples of these mechanisms are side flags <ref>{{Cite web |title=Matador Flag System Robot Upgrade Parts Jsumo {{!}} JSumo.com |url=https://www.jsumo.com/matador-flag-system |access-date=2025-01-03 |website=www.jsumo.com/ |language=en}}</ref> and side wedges,<ref name=":26">{{Cite web |title=Instagram |url=https://www.instagram.com/p/DCXbhKVBDUd/?utm_source=ig_web_copy_link&igsh=MzRlODBiNWFlZA== |access-date=2025-01-03 |website=www.instagram.com}}</ref> which are usually activated with actuators other than the driving motors.
[[File:Galena Sumo3kg ThundeRatz.jpg|thumb|Mega Sumo Galena, from ThundeRatz <small>[<nowiki/>[[:pt:ThundeRatz|pt]]<nowiki>]</nowiki></small> ([[Polytechnic School of the University of São Paulo|Poli-USP]]), is an example of robot with side blades.<ref name=":26" />]]

=== Electronics ===
In a sumo robot, [[Electronics]] may be divided in two main functions: power supply and logic control.<ref name=":9" /> Sumo robots, in general, employ [[Lithium polymer battery|Lithium polymer batteries]] to supply energy to the motors and other electronic components.<ref name=":10" />

[[Microcontroller|Microcontrollers]] are mainly employed to receive data from sensors and send command to the motors and other actuators based on the programmed control logic. Microcontrollers are usually mounted with a designed [[Printed circuit board|PCB]] for the robot.<ref name=":10" />

In Autonomous classes, [[infrared]] sensors or [[Ultrasonic transducer|ultrasonic sensors]] are usually employed to detect the opponent.<ref name=":10" /> Sumos also employ sensors to detect the edge (border line), usually with [[Photodiode|phototransistor]] reflectance sensors.<ref>{{Cite web |title=Ultimate Robot Parts & Robot Kits Shop for Robot Makers |url=https://www.jsumo.com/qtr-8a-line-sensor-analog |access-date=2025-01-03 |website=www.jsumo.com/ |language=en}}</ref>

In RC classes, the robots are remotely controlled by an operator. All Japan Robot-Sumo Tournament usually require [[Radio control|radio controllers]],<ref name=":4" /> so the robot hardware must be able to receive commands from the controller using a [[Radio receiver|radio signal receiver]] module.

=== Programming ===
The [[Computer programming|Programming]] discipline is responsible for the [[Embedded system|embbeded]] [[control system]], mainly in the autonomous classes.<ref name=":10" /> A robot-sumo [[firmware]] is responsible monitoring the sensors' data and for controlling the actuators, such as the driving motors.

The robot [[control system]] consists in setting the behaviour of the actuators (mainly the motors) based on the feedback of the sensors. Some usual control routines include setting a behaviour while no opponent is detected, such as randomly advancing through the dohyō, and a behaviour when an opponent is detected, such as pursuing it based on the feedback of the detection sensors.