Performance Analysis And Experimental Study On Liquid Damping Vibration Isolator Of Driver's Seat

Since automobile was invented,ride comfort has always been the focus of automotive performance research.Commercial vehicles,especially heavy trucks,usually improve driver ride comfort with the help of seat suspension.As the core of the seat suspension,it is very important to select the vibration isolator.The performance of bellows-type liquid damping vibration isolator is excellent,and the reliability is satisfied.However,there are fewer instances on automotive system.In this paper,the feasibility of the new type of seat suspension is studied based on the analysis of the performance of bellows-type vibration isolator.The article starts from the theoretical research,where mathematical expression of bellows-type vibration isolator is established.Based on theoretical research,the dynamic characteristics calculation software is written in MATLAB,which is as a design tool to study the influence of the key parameters on the performance of the isolator.Then combining practicality,the static and dynamic performance of the isolator is further studied through finite element simulation and experimental verification.Finally,the performance of the bellowstype vibration isolator in the seat suspension system is studied.In theoretical analysis,by comparing each formula,and the empirical formula which is suitable for this paper is selected.The equivalent two degree of freedom model is established to analyze the equivalent stiffness and equivalent damping coefficient.Furthermore,the transfer rate is studied.It is found that the low frequency transfer rate of the bellows-type vibration isolator is close to the spring damper,and the high frequency transfer rate is lower due to the equivalent mass of the liquid in the damping channel.Under the same conditions,the vibration isolation performance of the bellows-type vibration isolator is better.In software analysis,the dynamic characteristics calculation software is written in MATLAB GUI,as a research tool to analyze the influence of key parameters on the performance of isolator.The results show that the excitation amplitude,the diameter of the damping channel and the stiffness of the end of the isolator are more sensitive to the dynamic performance.Parameter optimization should aim at these parameters.The finite element model of bellows-type liquid damping isolator is established with the sample.Through finite element software ADINA,the static stiffness is calculated and compared with theoretical formula,and there is a good agreement.Meanwhile,the dynamic characteristics of the isolator are calculated by the direct method of fluid solid coupling,compared with the results of software calculation,the correctness of software calculation is verified.Taking efficiency into account,software is more inclined to use for design analysis.It is found that due to the radial stiffness of bellows,the dynamic stiffness will decrease slightly at high frequency.The error of this part should be considered in software design.The bench test of two vibration isolators was carried out by using the rubber dynamic testing machine.The static stiffness of two samples is obtained,and the dynamic stiffness and damping angle characteristics are obtained by the sweep frequency method.The static stiffness is compared with the empirical formula and finite element simulation,and the dynamic characteristics are compared with the software simulation,which are in good agreement with each other.Therefore,the static stiffness is designed by empirical formula,and the dynamic characteristics of the system are analyzed by the software.Finally,through MATLAB/Simulink,the four degree of freedom model of 1/4 car seat is established to study the actual performance of the seat suspension with bellows-type vibration isolator.It is found that the ride quality indices of the seat system and the dynamic travel of the seat suspension are within a reasonable range to meet the design requirements,which is to further study the realization of the bellows-type vibration isolator on the seat suspension.In this paper,the bellows-type liquid damping vibration isolator is studied,and a perfect design technique is formed.At the same time,the feasibility of the vibration isolator in seat suspension is verified,which lays the foundation for further research and design.