Design and Test of Automatic Steering System for Electric Vehicle Using Lab VIEW

摘要

With the rapid development of the modern vehicle industry, the demand for the automatic steering control of electric vehicles is increasing. To improve the steering accuracy, an electric golf cart was served as the test vehicle. The system mainly includes the stepper motor, stepper motor driver, steering controller, and angle sensor. The angle sensor inputs the voltage signal into the NI myRIO steering controller; the steering controller obtains the current angle through a calibration formula and compares it with the expected angle; the driving signal of the corresponding action is transmitted to the stepping motor driver to drive the rotation of the moor. Then, the steering shaft is driven by the reducer and EPS device, which makes the wheel rotate to the required angh. A control strategy for the automatic steering system was established, and an adaptive fuzzy PID controller was designed using Lab VIEW. This strategy includes three modules: motor phase control, motor speed control, and safety protection. To verify the actual performance of the designed automatic steering system for electric vehicles, the validity of the adaptive fuzzy PID algorithm was verified through a bench test and real vehicle test. Bench test results revealed that the stepresponse time was 1.2 s, the maximum deviation was 0.607°, and the average deviation was 0.318°. Real vehicle test results revealed that the maximum deviation was 0.754° and the average deviation was 0.389°. This system simplifies the hardware structure and improves the adaptability of automatic steering control. The precision can meet the requirements of electric vehicle steering.