The reformation of the horizontal mechanism: we make the horizontal ball lead screw instead of the conventional screw. And Stepper motor drives the screw.

横向进给机构的改造：拆除横向丝杠换上滚珠丝杠，由步进电机带动。

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To increasing the automation degree of rut tests and controlling the small car route conveniently, a stepper motor replaces the traditional crank connecting rod organization for small car drives;

为了提高车辙测试的自动化程度，在进行车辙试验时方便地控制测试小车的行程，用步进电机驱动小车代替传统的曲柄连杆机构驱动；

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