If you've never heard of sumo bots, you'd be forgiven for imagining futuristic hulking mecha-sumo-wrestlers, battling it out in the dohyo. But in fact, you'd not be so far from the truth, apart from the size. Sumo robots are clever little wheeled machines that are programmed to do exactly what a Sumo wrestler does - push its opponent out of the ring.
Sumo robot competitions and tournaments take place throughout the world. These are divided into various classes determined by size and weight. Generally the robots are self-controlled machines, using a system of sensors that allows them to detect their opponent and push it out of play. These sensors can identify the edge of the ring, too, enabling a robot to make evasive moves if necessary.
The most successful competitive robots are built from scratch by enthusiasts. These can often sport arms, scoops and angled shovels, all designed to upend their opponents off their wheels and push them out of the ring. Sumo bots built for competition must conform to certain rules, so as not to damage either the ring or their opponent.