International Journal of Intelligent Engineering and Systems

8

Authors: Jie Gao, Ke Chen

Vehicle ride comfort is one of the important properties of modern car. This paper takes a practical model for reference section and a virtual model is established based on virtual proving ground (VPG). By calculating and analyzing simulation results, we can comprehensively and accurately evaluate the model, and do further study of different factors impacting on ride comfort. The main researches include: the multi-body dynamics model and random road surface are established based on VPG. The body acceleration time-domain curves and frequency-domain power spectrums are obtained by LS-DYNA. Total weighted acceleration of vehicle ride comfort is evaluated by root-meansquare method. The effects of suspension system, tire pressure and speed on the vehicle ride comfort are analyzed. Simulation results show that the simulation of vehicle ride comfort based on VPG can truly reflect real test condition and the results achieved are accurate and reliable.

10

Authors: Ze Tao, Xiaoxia Liu

IA Petri net controller method for Petri net model with uncontrollable transitions that enforces the conjunctions a set of linear inequalities on the Parikh vector or place markings is proposed. The method for constructing a Petri net feedback controller is based on part design and Petri net reduction technique. Constraints are classified into admissible and inadmissible constraints. Matrix-Transformation method is proposed to transform the inadmissible constraint into admissible one to construct the controller. The method eases the design of controller and holds remarkable advantages especially for systems with large scale, because it only considers local incident matrix related to the place and Parikh constraints and uncontrollable transitions. Finally, the method is proved to be simple and efficient through some examples.