This paper describes a digital control system developed to reduce the inertial effects of an electrically assisted power steering system. Hydraulic power steering systems have been replaced by electric motors for fuel efficiency, but electric motors alone have a lot of inertia. This mechanical inertia makes steering harder at the start and end of a turn. It is compensated for by using the digital control system to control the motor. We designed the system using a linear model and PID controller whose gain is adjusted with a simulation.
The combination of the linear model and PID controller provides a smooth algorithm by removing the mechanical catch-up present in open-loop systems. Then, by modeling the steering system, we found its characteristics, which were used to conform the model by testing it with the simulation. Further hardware testing verifies the reduction of inertial effects and increased steering comfort.
