Fig. 1. Block diagram of hardware

Fig. 2. Function dividing of controller

Fig. 3. Motor drive circuit

Fig. 4. Sequence diagram of LMD18200 circuit

Fig. 5. Sequence diagram of ADS8866 circuit

Fig. 6. Sequence Diagram of encoder circuit

Fig. 7. Structure diagram of series PID

Fig. 8. PID control model

Fig. 9. System Simulation Model Diagram

Fig. 10. Step simulink diagram

Fig. 11. Step response curve of system position