A suspension design process for passenger vehicles is demonstrated to meet the vehicle directional control response parameters. This process has been proved to be a satisfactory proactive design tool for suspension engineers to minimize time and cost at up-front design stage. The whole process consists of three phases: (1) identifying the sensitive suspension parameters affecting vehicle handling; (2) selecting the appropriate suspension parameters to meet target handling values; and (3) evaluating proposed suspension alternatives in different handling conditions such as cornering at high lateral acceleration, braking/thrust in a turn and step-steer transient analysis. Based on Taguchi's orthogonal fractional factorials, a 10-degree-of-freedom vehicle simulation model is used to rank the severity of the input suspension factors to the selected output handling parameters and to evaluate the handling performance of different suspension alternatives. Moreover, a case study is performed to determine quantitatively how various body structure, suspension components, wheel hub bearing compliances and rubber bushing rates affect the overall suspension compliances which play important roles in handling parameters. (A)
Abstract