A sky-hook positive real network based ISD seat suspension for commercial vehicle

In order to meet the needs for large loads, commercial vehicles need to use extremely high suspension stiffness, and it is impossible to design the suspension structure parameters of commercial vehicles with the driver’s ride comfort as the performance orientation. To address the potential health hazards to drivers of commercial vehicles caused by vibration from road impacts when traveling in poor road conditions, this paper proposes a seat ISD (Inerter-Spring-Damper) suspension system based on sky-hook damping control coupled with positive real network. Firstly, a three-degree-of-freedom seat ISD suspension model coupled with sky-hook positive real network is constructed, and the ISD suspension vibration isolation mechanism is investigated. To ensure the passivity and stability of the structure, the biquadratic impedance of five components was optimized under the constraint of positive real conditions. After that, a seat ISD suspension control system based on model reference adaptation is designed. The experimental results show that the proposed seat ISD suspension reduces the seat acceleration by 24.48% (from 1.47 m/s 2 to 1.11 m/s 2 ), the suspension working space by 12.60% (from 0.015 m to 0.0131 m), and the peak seat vibration transmission rate by 16.70% compared to passive seat suspension, under Class C random road input conditions. This study effectively expands the design ideas of seat suspension and provides guidance and support for seat suspension research.