Design of reduced-order controllers via H∞ and parametric optimisation:: Comparison for an active suspension system

The design of reduced-order controllers under specific performance and structure requirements is dealt in this contribution. Two controllers are designed and compared. The first one was designed using H-infinity theory whereas the latter one is designed departing from a parametric-optimisation via a two-stage algorithm. The time spent by the designer using our second approach is largely reduced. An active suspension system is selected as a case study. The performance of both controllers is tested experimentally in the active, suspension set-up. The experimental results show that the parametric-optimisation controller practically meets the desired performance specifications. Meanwhile, the H-infinity controller cannot accomplish the imposed constraints just in the low-frequency range.