Combined vehicle and hydraulic simulation models for the development of a prototype suspension system

Computer based time domain simulation is a common tool used in the early development stages of many mechanical and hydraulic systems. However, it is not always straightforward to examine the interaction of complex mechanical and hydraulic components within one simulation environment. This study examines the development of a hydraulically actuated roll control suspension for a passenger vehicle. The importance of combining accurate vehicle and hydraulic dynamic system models is highlighted. The fluid power simulation package BATHfp has been used extensively during the development of a prototype road going vehicle. The development of a fourteen degree of freedom vehicle ride and handling model and its integration with a large number of detailed hydraulic models has enabled the electrohydraulic and mechanical systems to be examined in detail. The use of simulation for selecting the suspension actuators, control valve, pump and piping is illustrated. The shortfalls of considering hydraulic and vehicle models in isolation are highlighted by the comparison of naive and sophisticated models.