The Random Vibration Study On The Damp Seat Of Agricultrue Vehicle

The agricultural vehicle would create strong vibration when it had driving because of the random motivation of irregularity road, which influenced the health of driver and steering stability severely. As a basic device of vehicle, it was parts that contacts human directly, it can relax the impact to human from the irregularity road and lighten the vibration, and create a comfortable work conditions for drivers. Therefore, it has important theory and practice meaning to study the seat under the random vibration.Made the X type damp seat of agricultural vehicle as the prototype, equivalent the nonlinear vibration model of human-seat-road to six-degree-of-freedom linear system by the nonlinear vibration theory, and MATLAB simulation software, and mathematical analysis. The system had analyzed by theoretical, and solved by the mathematical models, and verified through physical prototype testing. It had studied the feasibility of nonlinear systems linearization, and the mean square response of human body under the random vibration, and the impact of human comfort with the parameters of seat and the speed of agricultural vehicle. At the same time, the parameters influenced the capability of damp seat has been optimized according to ISO2631 standards. The results proved: when the rigidity k₂ of the main constringent spring was 8511N/m, the rigidity k₂' of the vice constringent spring was 8000N/m, the rigidity k2" of the drawing-extending spring was 29823N/m and the equivalent damp coefficient C of the damper was 1082N·s/m, the acceleration which transferred from damp seat of agricultural vehicle to human body, that below 8h in the vibration criterion curve of ISO2631 when the frequency ranged from 4 to 8Hz. Through physical prototype test verification, the damping performance of seat suspension that optimized the parameters better than the original seat.