This paper presents an integral admittance control algorithm as an assistive controller for a vehicle with an Electric Power Steering (EPS) system. The driver’s input torque, measured by the torsion bar, is processed by an integral admittance model that generates the desired extra rotation angle for the EPS motor. As the motor tries to move the steering column ahead of the driver’s hand, it enhances the steering feel by reducing the impedance felt by the driver. The driver is modeled as a predictive path tracking controller, with a future point prediction scheme, that makes the vehicle follow the desired trajectory by using real-time data such as the x, and y coordinates of the desired path and those of the current position of the vehicle, yaw angle, vehicle speed and path curvature. The driver also predicts the future x and y coordinates of the vehicle to improve tracking accuracy. Simulations were performed using co-simulation between Adams/Car and MATLAB Simulink, capturing complex vehicle dynamics. The results demonstrate a significant reduction in driver effort while maintaining high path-tracking precision with minimal errors, indicating that the integral admittance control provides the system with smoother and more responsive steering and enhances both steering feel and driving performance.

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