Micromouse is an event where small

robot A robot is a machine—especially one programmable by a computer—capable of carrying out a complex series of actions automatically. A robot can be guided by an external control device, or the control may be embedded within. Robots may ...

mice solve a 16×16 maze. It began in the late 1970s. Events are held worldwide, and are most popular in the UK,

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, Japan,

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and becoming popular in subcontinent countries such as Sri Lanka. The maze is made up of a 16×16 grid of cells, each 180 mm square with walls 50 mm high. The mice are completely

autonomous robot An autonomous robot is a robot that acts without recourse to human control. The first autonomous robots environment were known as Elmer and Elsie, which were constructed in the late 1940s by W. Grey Walter. They were the first robots in history ...

s 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 run that route in the shortest possible time. Competitions and conferences are still run regularly.

Half-Size Micromouse

A new version of Micromouse called the Half-Size Micromouse has been introduced for 30th All Japan Micromouse Competition 2009. Instead of a 16×16 maze, the new competition uses up to a 32×32 maze. Cell and wall dimensions have been reduced by half, providing a new challenge There have been half-size competitions in Europe in Hungary in 2015 and the UK in 2018.

Maze solving

Mice can use various

searching algorithms In computer science, a search algorithm is an algorithm designed to solve a search problem. Search algorithms work to retrieve information stored within particular data structure, or calculated in the search space of a problem domain, with eit ...

. Common search algorithms use variations of the Bellman flood-fill method,

Dijkstra's algorithm Dijkstra's algorithm ( ) is an algorithm for finding the shortest paths between nodes in a graph, which may represent, for example, road networks. It was conceived by computer scientist Edsger W. Dijkstra in 1956 and published three years ...

A* search algorithm A* (pronounced "A-star") is a graph traversal and path search algorithm, which is used in many fields of computer science due to its completeness, optimality, and optimal efficiency. One major practical drawback is its O(b^d) space complexity, ...

, among various

graph traversal In computer science, graph traversal (also known as graph search) refers to the process of visiting (checking and/or updating) each vertex in a graph. Such traversals are classified by the order in which the vertices are visited. Tree traversal ...

and

tree traversal In computer science, tree traversal (also known as tree search and walking the tree) is a form of graph traversal and refers to the process of visiting (e.g. retrieving, updating, or deleting) each node in a tree data structure, exactly once. ...

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, Ng Beng Kiat and Fumitaka Nakashima. The current world record is 3.921 seconds 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 10 m/s². 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. 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

{{Reflist, 30em Robotics competitions