车辆液压动力转向系统通过伺服阀控制压力油的方向和流量，把转向盘输入的转角信号转变为车轮的偏转角度输出。

Vehicle power steering systems control direction and flow of pressure oil with servo valves, then transfer angular inputs from steering wheels to corner angular outputs of road wheels.

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在油源设备提供一定压力油液的情况下，计算机调整输入到液压缸内的油液流量，由此控制试验载荷。

With the digital control, volume of compressive oil provided by hydraulic power unit in actuator can be regulated to modulate the test load value.

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