Design and evaluation of cab seat suspension system based on negative stiffness structure.

To improve the vibration-isolation performance of cab seats, the optimization model of the seat suspension system of construction machinery cabs is proposed based on the negative stiffness structure. The negative stiffness nonlinear kinetic equation is established by designing the seat negative stiffness suspension structure (NSS). Using MATLAB, the different parameters of the suspension system and their influences on the dynamic stiffness are analyzed. The ideal configuration parameter range of the suspension system is obtained. Meanwhile, the optimization model of NSS is proposed, and the vibration transmissibility characteristics are simulated and analyzed by different methods. The results show that the displacement and acceleration amplitudes of the optimized seat suspension system are evidently reduced, and the four-time power vibration dose value and root mean square calculation values in the vertical vibration direction of the seat decrease by 86% and 87%, respectively. Seat effective amplitude transmissibility (SEAT) and the vibration transmissibility ratio values also decrease. Moreover, the peak frequencies of the vibration transmitted to the driver deviate from the key frequency values, which easily cause human discomfort. Thus, the design of the seat suspension system has no effect on the health condition of the driver after being vibrated. The findings also illustrate that the NSS suspension system has good vibration-isolation performance, and the driver's ride comfort is improved. [ABSTRACT FROM AUTHOR]