Design Of The New Passive Suspension Based On Quasi-Zero-Stiffness Theory

Suspension system plays a crucial role in ride comfort and safety.The quasi-zero stiffness structure can reduce the dynamic stiffness of the system without reducing the static stiffness.Thereby,it can greatly reduce the amplitude of the low frequency band of the vibration system.Therefore,the passive quasi-zero stiffness suspension helps to reduce the low frequency resonance peak of the suspension,and helps to improve vehicle ride comfort.As a result of active or semi-active approach to achieving quasi-zero stiffness has the disadvantage of increasing suspension system energy consumption,this paper combined the passive quasi-zero stiffness structure with the vehicle suspension.A passive quasi-zero stiffness suspension structure is proposed.Comparatively,the applicability of various implementations of passive quasi-zero stiffness structures in vehicle suspension systems was demonstrated.The dynamic characteristics of various combinations of disc springs and coil springs were studied.A passive quasi-zero suspension structure which uses disc spring assembly in series with a coil spring as the key part was designed.By analyzing the mechanical properties of the disc spring and its assembly,a numerical model of the stiffness characteristics of the disc spring assembly was established.Using a press to measure the stiffness characteristic curve of the disc spring assembly,the numerical model parameters were identified,and the correctness of the numerical model of the disc spring assembly was verified.Based on this,a simulation model of 1/4 passive quasi-zero stiffness suspension was established.The influence of passive quasi-zero stiffness device parameters on suspension performance is analyzed.The passive quasi-zero stiffness suspension is compared with the traditional passive suspension.The result showed that the passive quasi-zero stiffness suspension can significantly improve the vehicle ride comfort,thus verifying the feasibility of the design.Finally,a passive quasi-zero suspension prototype was designed and built a 1/4 suspension test-bed which based on a 1/4 passive suspension test-bed.The performances of passive quasi-zero stiffness suspension and traditional passive suspension were compared and analyzed in time domain and frequency domain by input multiple sets of random road excitation to the suspension,and the correctness of the theoretical analysis is verified.