Automatic navigation system for electric power vehicles with EPS

In this research, automatic navigation control system is developed for agricultural electric power vehicles. Electric power steering (EPS) systems have many advantages over traditional hydraulic power steering systems in engine efficiency and space efficiency. So the electric power vehicle for experiment equips EPS system. Navigation control method, fuzzy control steering and path planning are discussed in detail. Navigation control method adopts preview following method. Fuzzy control method is used for automatic steering and fuzzy controller is developed. Cross track error (XTE) and direction error are two input variables of fuzzy controller. In the automatic navigation system, RTK-GPS, digital compass, and angle sensor are equipped to acquire the position and posture information of the vehicle. Through fuzzy control for steering and path tracking algorithm, the electric vehicle realizes automatic navigation. Navigation control software system is developed using VC++. At the end of the paper computer simulation and application experiment are implemented. Test results indicate that the cross track error was less than 0.3 m when the vehicle ran following the predefined line path.