MODELING AND SIMULATION OF ACTIVE HYDRO-PNEUMATIC SUSPENSION SYSTEM THROUGH BOND GRAPH

Abstract

This article presents a model for active hydro-pneumatic (AHP) suspension system. This is a relatively new suspension design, in which the system works without the classical mechanical parts of a suspension, such as steel springs and dampers. Instead, a hydraulic system is used which consists of a plunger cylinder, a flow resistance, a hydro-pneumatic capacitor and a strong hydraulic pump together with a fast response servo valve. At the heart of each AHP suspension system, there is a force controller, which is responsible for tracking a certain desired force. The modeling of the system has been made using the bond graph simulation technique. All of the components of the system have been replaced by their bond graph counterparts. The governing equations are written in terms of bond graph models, and are solved simultaneously.  Bond graph results are compared to the results of others. The bond graph method succeeds in reproducing the same outputs as the other methods. However, the ability of the bond graph modeling in adapting to new changes in the system components and physical models makes it a good choice for complex systems.

http://dx.doi.org/10.5755/j01.mech.17.3.509