Principle Design And Control Of An Integrated Semiactive Seat Suspension For Both Longitudinal And Vertical Vibration Attenuation

Engineering vehicles,cross-country vehicles and other off-road vehicles generate both longitudinal and vertical vibrations due to road potholes,bumps and inevitable falling down or climbing during moving.These vibrations may reduce ride comfort and security of the drivers.To simultaneously suppress both longitudinal and vertical vibrations,in this paper,the principle and prototype system of an integrated semi-active seat suspension based on “Functional integration” concept,mainly composed of a switching mechanism,a transmission amplification mechanism,and a damping force-or torque-controllable rotary magnetorheological(MR)damper,for both longitudinal and vertical vibration attenuation is proposed,designed,fabricated,and tested.The switching mechanism employs the parallelogram frames as a motion guide which keeps the seat moving longitudinally and vertically.Both longitudinal and vertical motions are transformed into a reciprocating rotary motion that is transmitted to the rotary MR damper after an amplification by a gear mechanism.The torque generated by the MR damper can be tuned through adapting the applied current in real time and thence effective two-dimensional vibration control of the seat could be realized.The mathematical model of the semi-active seat suspension system is established,and vibration transfer characteristics of the system is simulated and analyzed.The vibration control performances of the seat suspension system under passive,semi-passive,and semi-active fuzzy control are compared and analyzed.Based on the established experimental test rigs,the prototype of the seat suspension system is tested,and the results of the mathematical model and the experimental test are compared.The vibration control performances of the seat suspension under different controls are also tested and verified.