Keywords: active suspension, hydropneumatic suspension, differential geometry, feedback linearisation, hydropneumatic springs, PID control, vehicle suspensions, vehicle vibration, missile launching, launch vehicles, nonlinear controllers, linear control, modelling
PID control for active hydropneumatic suspension based on the feedback linearisation
Based on modelling and experimental validation of the hydropneumatic spring, a non-linear dynamic model is developed for the active hydropneumatic suspensions of missile launching vehicle. In order to fulfil the special requirements of mobile launching, the non-linear system is transformed into a linear one by means of feedback linearisation (FBL) according to the theory of differential geometry. Furthermore, a PID control approach is applied for the solution to the system of equations. It is indicated by the simulation results that the present non-linear controller combining the FBL with linear control algorithm is characterised with its fairly simple structure and good performance.