An experimental and theoretical investigation into the design of an active suspension system for a racing car

The well-established quarter car representation is used to investigate the design of an active suspension system for a racing car. The work presented is from both a practical and theoretical study. The experimental open-loop and passive responses of the suspension system are used to validate the model and estimate the level of damping within the system. A cascade control structure is used, consisting of an inner body acceleration loop and an outer ride height loop. Comparisons are made between the experimental results and those predicted by the theory. During the 1980s and early 1990s a number of Formula 1 teams developed active suspension systems to improve the performance of cars. Little detail was published about these systems because of the highly competitive nature of the application. Some of these systems were very sophisticated and successful. Because of this, speed increased considerably and because of the costs involved, the difference in performance between the lower and higher funded teams became unacceptable. For this reason, the governing body of motor sport decided to ban active suspensions from the end of the 1993 racing season. Both authors of this paper were involved with different racing teams at that time, and this paper is an introduction to the very basic philosophy behind a typical active system that was employed on a Formula 1 car.