Vehicle with offset extendible axles and independent four-wheel steering control

摘要

A vehicle includes a chassis supporting two front axle assemblies and two rear axle assemblies. Each of the front and rear axle assemblies includes an extendible and retractable axle supporting an independently steerable wheel and a steering mechanism. The axles of the respective front and rear axle assemblies are offset from each other. By providing independently steerable wheels, the vehicle is operable in a plurality of steering modes including two-wheel steer, crab steer and coordinated steer. A steering angle for each steering wheel is determined according to a steering angle of an inside front wheel on a turn-by-turn basis.