3次元機構解析によるベルクランク方式サスペンションの入出力特性計算法に関する検討

Abstract

The spring and shock absorber of automotive suspension systems play a key role in vehicle maneuverability, stability and riding comfort. Using the double wishbone type front suspension with bell crank and pushrod as a model, this paper introduces a calculation method for clarifying the relativity of the spring characteristic in vertical direction on the tire contact patch and the suspension coil spring characteristics using expressions derived directly from a three-dimensional kinematics of mechanism theory that considers suspension/ steering link geometry. Next, this paper reports findings from calculations of spring characteristics using a newly created three-dimensional model and compares them to results obtained from a previously developed two-dimensional simplified model based on data that measures individual link pivot coordinates of the suspension/ steering geometry of a small on-the-market racing car. Results verify the accuracy of the three-dimensional model and indicate areas in need of correction in the two-dimensional model.