Preventing Lower Back Pain Among Truck Drivers: Design and Performance of a Controlled Slippage Magnetorheological Actuator for an Active Seat Suspension

Abstract

Passive air-spring suspensions are widely used in modern heavy vehicle seat suspensions because they provide a fair isolation from road vibrations while remaining relatively cheap. However, only expensive active suspensions can completely relieve drivers from serious health risks due to whole body vibration as prescribed by the ISO-2631-1 standard. This article sets out the design and experimental validation of a simple and affordable active seat suspension that uses a controlled slippage magnetorheological (MR) actuator. The open-loop dynamic performance of the actuator is assessed experimentally in accordance with the requirements of an active seat suspension actuator. Results show that the actuator can develop a maximum vertical force of 1000 N, has a force cutoff frequency of 15 Hz and displays a high level of transparency that can match the dynamic requirements of an active seat suspension. This force cutoff frequency is about three times higher than that of commercially available hydraulic active seat suspensions. Experimental results of on-road tests performed in a long-haul truck using an LQG controller also confirm that the performance of the active seat suspension can match that of commercial alternatives, thus reducing drivers’ exposure to vibrations below upper safety limits.