Steering rear axle of truck: separate electrohydraulic mechanism

Useful to know

Bosch describes electrohydraulic rear-axle steering for heavy trucks. An electrically driven pump, cylinder and sensor produce the requested rear-axle steering angle. [1]

The front steering angle is communicated over CAN, and the controller calculates the desired rear position. This is a specific truck implementation, not a description of every car with four-wheel steering. When comparing chassis, establish which axle is steered and in which configuration. Axle count alone does not reveal which wheels turn or how they are controlled.