Title: Optimum characteristics of automotive shock absorbers under various driving conditions and road surfaces
Authors: N. Fukushima, K. Hidaka, K. Iwata
Addresses: Research Engineers, Vehicle Research Laboratory, Central Engineering Laboratories, Nissan Motor Co., Ltd., Yokosuka-shi, Japan. ' Research Engineers, Vehicle Research Laboratory, Central Engineering Laboratories, Nissan Motor Co., Ltd., Yokosuka-shi, Japan. ' Research Engineers, Vehicle Research Laboratory, Central Engineering Laboratories, Nissan Motor Co., Ltd., Yokosuka-shi, Japan
Abstract: Shock absorbers have a significant influence on handling performance and riding comfort. However, no further reduction of vehicle vibration can be expected from using the velocity-dependent damping characteristics of the shock absorber. Thus, it is necessary to make modifications to improve the functions of the shock absorber. In this study, we examined how input in the vertical direction affects the suspension under various driving conditions and road surfaces. The study was performed while the steering wheel was being operated and the vehicle driven on smooth and rough roads. We also focused on driving conditions where the shock absorbers exerted a significant influence. We then measured the piston velocity of the shock absorber and the operating range of the piston stroke. We also investigated the necessity of its damping force. The results clearly showed that the damping characteristic must be changed to concur with the piston stroke. Using both theoretical analysis and simulation, we obtained damping coefficients which met the requirements under the respective driving conditions. We then examined them together with the operating range data and made diagrams plotting damping force versus piston velocity. From this, we obtained the optimum damping characteristics dependent on piston stroke. The realization of these characteristics will enable us to satisfy the requirements for riding comfort, handling and other necessary performances.
Keywords: damping coefficient; driving conditions; vehicle handling; piston stroke; piston velocity; riding comfort; road surface; shock absorbers; vehicle suspension; vehicle design.
International Journal of Vehicle Design, 1983 Vol.4 No.5, pp.463 - 472
Published online: 25 May 2014 *Full-text access for editors Access for subscribers Purchase this article Comment on this article