Analysis of driving stability and smoothness based on magnetic negative stiffness suspension for cars

Abstract

Existing economy vehicles mostly use inexpensive passive suspensions, which struggle to fulfil the driving performance needs of people because of their fixed damping stiffness. This paper proposes to build magnetic suspensions by integrating inexpensive negative stiffness magnetic springs and passive suspensions to improve the suspension performance of such cars. Based on the constructed magnetic suspension model, simulations were conducted to investigate and analyse its stability and smoothness in various aspects. Finally, the performance was verified using experiments. The results demonstrate that adding magnetic springs in passive suspensions enables the total stiffness of the suspension to vary adaptively, enhancing the car’s driving stability. Furthermore, it also reduces the car body acceleration, the resonance interval of the suspension system and its displacement transmissibility, further improving the car’s ride smoothness. These performance benefits increase with increasing road excitation, and their role is more pronounced in off-road vehicles. This magnetic suspension system provides novel ideas for the further design of passive suspensions and lays the foundation for the future development of variable stiffness suspensions.