Micromouse

{{Short description|Competitive event involving small robotic mice}}

File:Micromouse maze.jpg

File:Micromouse Green Giant V1.3.jpg

Micromouse is an event where small robotic mice compete to solve a 16×16 maze. It began in the late 1970s.{{cite web |title=History |url=http://www.micromouseonline.com/micromouse-book/history/ |website=Micromouse Online |publisher=}} Events are held worldwide, and are most popular in the UK, U.S., Japan, Singapore, India, South Korea and becoming popular in subcontinent countries such as Sri Lanka.

The maze is made up of a 16×16 grid of cells, each 180 square mm with walls 50 mm high.{{Cite web |title=UK Micromouse Maze Solver Rules |url=https://www.cs.york.ac.uk/micromouse/Rules/Maze_Solver_Rules.pdf | archive-url=https://web.archive.org/web/20181201005335/https://www.cs.york.ac.uk/micromouse/Rules/Maze_Solver_Rules.pdf |archive-date=2018-12-01|website=University of York Department of Computer Science}} The mice are completely autonomous robots that must find their way from a predetermined starting position to the central area of the maze unaided. The mouse needs to keep track of where it is, discover walls as it explores, map out the maze and detect when it has reached the goal. Having reached the goal, the mouse will typically perform additional searches of the maze until it has found an optimal route from the start to the finish. Once the optimal route has been found, the mouse will traverse that route in the shortest achievable time.

Competitions{{cite web|url=http://micromouseusa.com/|title=Micromouse USA - USA Micromouse Fans Site|publisher=}}{{cite web|url=https://ukmars.org/index.php/Main_Page|title=UK Micromouse and Robotics Society|website=ukmars.org}} and conferences{{cite web|url=https://ukmars.org/index.php/Minos|title=Minos - UK Micromouse and Robotics Society|website=ukmars.org}} are run regularly.

Half-Size Micromouse

A version of Micromouse called the Half-Size Micromouse was introduced at the 30th All Japan Micromouse Competition in 2009.{{cite web|url=https://www.youtube.com/watch?v=bszRuwK3yIs |archive-url=https://ghostarchive.org/varchive/youtube/20211212/bszRuwK3yIs| archive-date=2021-12-12 |url-status=live|title=MicroMouse All Japan contest 2009 half size preliminary|last=robolaboN|date=22 November 2009 |publisher=|via=YouTube}}{{cbignore}}{{cite AV media| url-status = live| archive-url = https://ghostarchive.org/varchive/youtube/20211210/aN5vYrrSdKQ| archive-date = 2021-12-10| url = https://www.youtube.com/watch?v=aN5vYrrSdKQ| title = Japan 2009 half-size micromouse contest final | website=YouTube}}{{cbignore}} Instead of a 16×16 maze, the Half-Size competition uses up to a 32×32 maze. Cell and wall dimensions have been reduced by half,{{cite web|url=http://www.ntf.or.jp/mouse/micromouse2010/rulehalf-EN.html|title=NTF -New Technology Foundation-Micromouse2010|website=www.ntf.or.jp}} providing a new challenge.

Maze solving

{{See also|Maze-solving algorithm}}

Mice used in competitions employ the fundamental elements of robot navigation, including mapping, planning, and localization. Additionally, they optimize their path through the maze using various search algorithms. Common search algorithms use variations of the Bellman flood-fill method,{{Cite web|url=http://www.micromouseonline.com/micromouse-book/mazes-and-maze-solving/solving-the-maze/#axzz1uapduejO|title=Solving the maze}} Dijkstra's algorithm, A* search algorithm, among various graph traversal and tree traversal algorithms.

Performance

Mice can run at over three meters per second, depending on the maze design. Some of the best micromouse builders are Yusuke Kato,{{Cite web|url=http://blog.livedoor.jp/robolabo/|title=ロボット工作研究室 - livedoor Blog(ブログ)}} Ng Beng Kiat{{Cite web|url=https://sites.google.com/site/ngbengkiat/|title = Ng Beng Kiat}} and Fumitaka Nakashima.{{Cite web |url=http://homepage1.nifty.com/hfd01577/index.html |title=第4実験室 |access-date=2013-05-24 |archive-url=https://web.archive.org/web/20130605025335/http://homepage1.nifty.com/hfd01577/index.html |archive-date=2013-06-05 |url-status=dead }} The current world record is 3.921 seconds{{Cite web|url=https://spectrum.ieee.org/meet-the-new-worlds-fastest-micromouse|title=Meet the New World's Fastest Micromouse Robot|date=21 November 2011}} and is held by Ng Beng Kiat.

Performance in recent years has improved considerably. As of 2015, winning mice are likely to run with forward acceleration and braking well over 1g.{{cite web|url=http://www.micromouseonline.com/2017/08/03/micromouse-hard-acceleration/|title=Micromouse Hard Acceleration|first=Peter|last=Harrison|date=3 August 2017|publisher=}} Cornering with centripetal acceleration as high as 2g is possible. Micromice are among the highest-performing autonomous robots.

Most recently, robots are being equipped with a fan to create a partial vacuum under the mouse while it is running.{{cite web|url=http://www.micromouseonline.com/2017/10/11/taiwan-micromouse-intelligent-robot-contest-2017/|title=Taiwan Micromouse Contest 2017|first=Peter|last=Harrison|date=10 October 2017|publisher=}}{{cite web|url=http://www.micromouseonline.com/2018/02/18/more-suck-less-slip/|title=More suck, less slip|first=Peter|last=Harrison|date=18 February 2018|publisher=}}{{cite web|url=https://hackaday.com/2008/11/26/vacuum-micromouse/|title=Vacuum micromouse|last=By|date=27 November 2008|publisher=}} The additional downforce available has made possible a huge improvement in performance. Compared to a non-fan mouse, the newer robots are likely to be able to achieve centripetal accelerations of 6g or more. Straight line accelerations can easily exceed 2.5g.

References

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