Research on compliance steers of strut type front suspension subject to lateral force and self-aligning torque during cornering

• Published in: Kikai Gakkai ronbunshū = Transactions of the Japan Society of Mechanical Engineers Vol. 89; no. 919; p. 22-00301
• Main Authors: KAWATA, Tetsuaki, KOUNO, Tadashi, SAKUMA, Hitoshi
• Format: Journal Article
• Language: English; Japanese
• Published: The Japan Society of Mechanical Engineers 2023
• Subjects: Compliance steer; Lateral force; Self-aligning torque; Strut type front suspension
• ISSN: 2187-9761; 2187-9761
• DOI: 10.1299/transjsme.22-00301

In this paper, mechanism of compliance steers for lateral force and self-aligning torque is studied for strut type front suspension, which is commonly used in front wheel drive vehicle with transverse engine. First, through qualitative consideration, it is clarified that both of the compliance steers for lateral force and self-aligning torque consist of changes in toe-angle of three modes. Mode I is the change in toe-angle due to difference of displacements of the points on steering knuckle. Mode II is the change in toe-angle due to rotation of the lower arm. Mode III is the change in toe-angle due to displacement of the upper support of the suspension. In addition, it is shown that effects of design specifications of the suspension on the modes of compliance steer for lateral force and those for self-aligning torque are different. Based on this consideration, guidelines for design of strut type front suspension in terms of compliance steers for lateral force and self-aligning torque are presented. Then, CAE analysis for a suspension model based on a commercial vehicle is performed to confirm validity of the qualitative consideration as well as to show that compliance steer for self-aligning torque can have significance greater than that for lateral force.