Driver torque estimation in Electric Power Steering system using an H∞/H2 Proportional Integral observer

This paper deals with the design of a Proportional Integral (PI) observer to estimate the driver torque in an Electric Power Steering (EPS) system. The PI observer is obtained by solving a multi-objective optimization problem: it should both be barely sensitive to road disturbances and sensor noise, and converge swiftly. The performance of the proposed observer is illustrated by simulation results using experimental data.