H∞ loopshaping control of a steering wheel vibration simulator using complex lead filter

This paper presents the loopshaping control of a steering wheel vibration simulator using complex lead/lag shaping filter. The simulator is used in characterizing human perception of vibration as transmitted to the hand through the steering wheel. Accelerometers are used to record the acceleration at the top of the steering wheel in both the up-down (z) and side-to-side (y) directions. The plant is modeled using frequency response measurements including an uncertainty model generated from measured changes in system frequency response due to variations in subjects´ grip force. The resonances in the simulator frequency response and the desired performance requirement require sharp transitions in the loopshaping weighting filters that are difficult to achieve with typical first order lead/lag filters. Complex lead/lag filters were introduced to provide better trade-off considerations. Simulation results to verify the effectiveness of the proposed control algorithm are presented.