A vehicle comprises a vehicle frame, a prime mover mounted on the vehicle frame, a laterally turnable wheel disposed at one side of the vehicle frame, a pair of drive wheels disposed at the other side of the vehicle frame, a steering operation device, a traveling operation device for setting the traveling speed and direction of the vehicle, and a pair of transmissions for controlling the rotary speed and direction of the respective drive wheels. The transmissions are operationally connected with the steering operation device so as to create a difference of rotary speed between the drive wheels according to operation of the steering operation device. The transmissions are operationally connected with the traveling operation device so as to drive the drive wheels in a common rotary direction from their stationary state according to operation of the traveling operation device. A clutch is interposed between the transmissions so as to connect the drive wheels with each other when the steering operation device is set in a straight traveling position. Based on setting of a switching device for switching the traveling direction of the vehicle between forward and rearward, a reverser decides the rotational direction of the drive wheels.

A powertrain arrangement for selectively operating a vehicle in a skid-steer configuration is provided. The arrangement includes an engine coupled to a differential. A first torque transfer mechanism is coupled to a coupling mechanism and arranged to drive a first set of wheels on a side of the vehicle orientated parallel to a wheelbase of the vehicle. A second torque transfer mechanism is coupled to the differential and arranged to drive a second set of wheels on an opposite side of the vehicle. The coupling mechanism is coupled to the differential and includes a rotation selector arranged to selectively engage an output of the differential to provide a torque input to the first torque transfer mechanism of a direction so as to drive the first set of wheels in one of a same and an opposite direction as the second set of wheels.

A vehicle comprises a vehicle frame, a prime mover mounted on the vehicle frame, a laterally turnable wheel disposed at one side of the vehicle frame, a pair of drive wheels disposed at the other side of the vehicle frame, a steering operation device, a traveling operation device for setting the traveling speed and direction of the vehicle, and a pair of transmissions for controlling the rotary speed and direction of the respective drive wheels. The transmissions are operationally connected with the steering operation device so as to create a difference of rotary speed between the drive wheels according to operation of the steering operation device. The transmissions are operationally connected with the traveling operation device so as to drive the drive wheels in a common rotary direction from their stationary state according to operation of the traveling operation device. A clutch is interposed between the transmissions so as to connect the drive wheels with each other when the steering operation device is set in a straight traveling position. Based on setting of a switching device for switching the traveling direction of the vehicle between forward and rearward, a reverser decides the rotational direction of the drive wheels.

An electronic steering control system for controlling the lateral movement of a vehicle powered by a pair of hydrostatic drive devices, where the system controls a pair of actuators. Each actuator is configured to move a control member associated with one of the hydrostatic drive devices.

A vehicle comprises a steering operation device, a pair of running-driving wheels, which differentially drive when the steering operation device is manipulated, a pair of steerable running wheels interlocking with the steering operation device, and a steering mechanism interposed between the steering operation device and the pair of running-driving wheels. The steering mechanism includes a pair of drive gears interlocking with the steering operation device and a pair of follower gears interlocking with the respective steerable running wheels. The drive gears mesh with the respective follower gears so as to control lateral turning of the respective steerable running wheels. A gear radius of the drive gear may be greater than that of the follower gear meshing with it. A gear ratio between the mutually meshing drive and follower gears may be variable. The lateral turning centers of both the steerable running wheels may coincide with each other, and further coincide with a lateral turning center of the vehicle body caused by differential rotation of the running-driving wheels.