In the process of assembling the vehicle body and engine device, the body stops when it walks to a certain station on the friction line sling, and the positioning device is fixed. The chassis assembly stops when the roller is uploaded to this station, the positioning device locates the tray, and then the six-axis synchronous lifting platform synchronously reaches a certain position to complete the assembly of the body and the engine device. For the six-axis synchronous control system, the main axis and slave axis tracking control mode are adopted, and the main axis is the virtual axis set inside the controller, that is, the command axis. When the other six axes form their own servo position control loop, they simultaneously track the main axis through the electronic CAM to maintain synchronization, and the synchronization accuracy is 0.03mm. Since the scanning cycle of the control loop of each axis is less than 1ms, high-speed and high-precision position control (tracking) accuracy of each axis is ensured.
