Parking Assistance System Control Using a Disturbance Observer for Hybrid Electric Vehicles

This paper presents a remote smart parking assist (RSPA) control algorithm for hybrid electric vehicles based on a disturbance observer (DOB) and feedback control. The purpose of the proposed control algorithm is to improve the departure/stop agility and speed control performance of the RSPA. The DOB, activated when the hydraulic brake is released and vehicle departure initiates, estimates disturbances such as slippery road, road slope and bump road, and quickly compensates for these disturbances. The feedback controller corrects the motor torque based on the target speed and current vehicle speed. The gain of the feedback controller is adjusted according to the road gradient, which is estimated by a gradient observer. To validate the proposed control algorithm, actual vehicle test is performed using the Kia Niro Plug-in hybrid electric vehicle (PHEV). The results of the vehicle test show that the proposed control algorithm improves the robustness of the RSPA function.