Application of Permanent Magnets in Suspension and Recoil Buffer Systems

Abstract

Rare Earth Permanent Magnets (PMs) has inspired new applications in areas where magnets were not used before due to their outstanding magnetic characteristics. PMs such as Neodymium Iron Boron and Samarium Cobalt are now used extensively in a wide range of applications such as electrical machines, transducers and loudspeakers, energy storage systems, hybrid and electric traction drives, etc. This paper is concerned with the application of modern permanent magnets in automotive suspension systems which may be potentially utilized for recoil buffer systems in defence applications in the future. The objective is to investigate the possibility of replacing the mechanical coil springs with strong PM rings in order to improve the suspension performance and ride comfort. The research is based on the existing suspension of a scooter model type Honda PCX 125. The as-is suspension is first analyzed and the system main parameters, such as dimensions, stiffness and damping coefficients are determined. Mathematical model for the proposed PM rings pull force is developed. Parametric analysis and optimization on the number of magnets and dimensions is performed to achieve the predetermined design requirements. A Matlab/Simscape model for the proposed PM spring model is developed and compared with the as-is rear suspension of the scooter. Results of the simulation are analyzed and conclusions and recommendations for further research are presented at the end of this paper.

Keywords: permanent magnet springs, suspensions system, Matlab/simscape model;