Parametric Study of the Spring Force Line Effect on Vehicle Self-Steer for MacPherson Strut Suspension System

摘要

The MacPherson strut is widely used in the automotive industry. Many investigations regarding the minimization of damper friction force have been published; however, this is not the case with vehicle self-steer. There are several methods to reduce the amount of vehicle self-steer. The objective of this paper is to minimize vehicle self-steer with respect to spring force line position. To investigate the relationship between vehicle self-steer and spring force line, a mathematical model of suspension system was developed and then solved to obtain the optimum force line position that minimizes vehicle self-steer. The solution to the mathematical model found was that the force line must pass through the upper mount center in order to minimize vehicle self-steer, or the force line must be on the same plane as the kingpin axis. Sensitivity analysis was performed to investigate the variability of the force line position on vehicle self-steer. The result of the investigation will provide a guideline to design suspension coil spring with force line control.