| 摘要 |
A tracked vehicle has an electrohydraulic drive/steering system having an engine driven variable displacement hydraulic steering pump which drives a hydraulic steering motor which is coupled to a differential track drive mechanism via a transmission with multiple gear ratios. A steering wheel is coupled to a variable friction device which produces a variable friction force which resists rotation of the steering wheel. A control system is responsive to a position of the steering wheel and controls the steering pump displacement and controls the friction device. The control system sets the variable friction device to its high friction level when a limit of the steering pump displacement is reached when the transmission is in a higher one of its gear ratios. |
