Extraction of information from a PSD for the control of vehicle suspension

Abstract

Road irregularities are the main effect influencing driving quality, due to its unpredictability driver can not find the best driving parameters easily and fast. Identification of road profile lets us control the vehicle’s damping characteristics and increase driving quality as fast as possible. Power Spectral Density (PSD) could be easily found from the road profile. Deduction of road waviness and amplitudes from PSD could be used to provide the mandatory information required for controllable damping system. Using our developed dynamic model of the car, we performed a simulation of the vehicle passing artificially generated road profiles with different waviness. Obtained results show that the straight-line approximation of PSD of the road profile as recommended by ISO standard doesn’t provide suitable information required for the control of car suspension. We define that, two split approximations of PSD spectra is a better solution for this purpose. It provides reliable results and allows to choose optimal damping coefficient value with a small delay for long distances.