Patent ID: 7845458

Claim:
A control system for a frame-steered vehicle, said system comprising: a first steering cylinder and a second steering cylinder, which steering cylinders are arranged for frame-steering of the vehicle; and a first drive unit and a second drive unit, each of which comprises an electrical machine and a hydraulic machine; wherein each of said electrical machines is drivingly connected to its associated hydraulic machine; wherein a first of the two hydraulic machines is arranged for flow communication with a piston side of the first steering cylinder and a piston rod side of the second steering cylinder and a second of the two hydraulic machines is arranged for flow communication with a piston side of the second steering cylinder and a piston rod side of the first steering cylinder; and wherein for steering the vehicle in one direction, a first of the hydraulic machines is arranged to be driven by its associated electrical machine and to supply the hydraulic cylinders with pressurized hydraulic fluid and the second hydraulic machine is arranged to be driven by a flow of hydraulic fluid from the hydraulic cylinders and to drive its associated electrical machine, and vice versa.