A Hybrid Locomotion Vehicle for Nuclear Power Plants

A hybrid locomotion vehicle for use in remote maintenance of a nuclear power plant is proposed. The vehicle has five locomotion devices, each consisting of a supporting leg and a driving wheel. Each device has three degrees of freedom: leg lifting, wheel revolution, and wheel steering. These degrees of freedom and the inclusion of touch sensors for obstacle detection enable flexible locomotion such as stepping over rises and going up and down stairs in the plant. Two slope sensors set at orthogonal directions maintain vehicle posture through vertical leg motion. The control system, based on a microcomputer, supervises all of these motions. Laboratory tests with a prototype vehicle demonstrate successful locomotion.