Identification of low order vehicle handling models from multibody vehicle dynamics models

Download
2010
Sağlam, Ferhat
Vehicle handling models are commonly used in the design and analysis of vehicle dynamics. Especially, with the advances in vehicle control systems need for accurate and simple vehicle handling models have increased. These models have parameters, some of which are known or easily obtainable, yet some of which are unknown or difficult to obtain. These parameters are obtained by system identification, which is the study of building model from experimental data. In this thesis, identification of vehicle handling models is based on data obtained from the simulation of complex vehicle dynamics model from ADAMS representing the real vehicle and a general methodology has been developed. Identified vehicle handling models are the linear bicycle model and vehicle roll models with different tire models. Changes of sensitivity of the model outputs to model parameters with steering input frequency have been examined by sensitivity analysis to design the test input. To show that unknown parameters of the model can be identified uniquely, structural identifiability analysis has been performed. Minimizing the difference between the data obtained from the simulation of ADAMS vehicle model and the data obtained from the simulation of simple handling models by mathematical optimization methods, unknown parameters have been estimated and handling models have been identified. Estimation task has been performed using MATLAB Simulink Parameter Estimation Toolbox. By model validation it has been shown that identified handling models represent the vehicle system successfully.

Suggestions

Design and simulation of an ABS for an integrated active safety system for road vehicles
Şahin, Murat; Ünlüsoy, Yavuz Samim; Department of Mechanical Engineering (2007)
Active safety systems for road vehicles have been improved considerably in recent years along with technological advances and the increasing demand for road safety. In the development route of active safety systems which started with introduction of digital controlled ABS in the late seventies, vehicle stability control systems have been developed which today, with an integration approach, incorporate ABS and other previously developed active safety technologies. ABS, as a main part of this new structure, s...
Experimental determination of transfer functions for a car body-in-white
Şentürk, Sabri; Ünlüsoy, Yavuz Samim; Department of Mechanical Engineering (2004)
Vibration generated from various sources (engine, road surface, tires, exhaust, etc.) should be considered in the design of a car body. These vibrations travel through transfer systems (drivetrain, suspension, body, etc.) to the steering wheel, seats and other areas where it is detected by the passengers of the vehicle. Transmission routes must be studied and efforts made to keep transfer systems from amplifying vibration and to absorb it instead. Since the superior vibration transfer system is the car body...
Internal ballistic design optimization of a solid rocket motor
Açık, Sevda; Dursunkaya, Zafer; Department of Mechanical Engineering (2010)
Design process of a solid rocket motor with the objective of meeting certain mission requirements can be specified as a search for a best set of design parameters within the overall design constraints. In order to ensure that the best possible design amongst all achievable designs is being achieved, optimization is required during the design process. In this thesis, an optimization tool for internal ballistic design of solid rocket motors was developed. A direct search method Complex algorithm is used in th...
Development of a control strategy for road vehicles with semi-active suspensions using a full vehicle ride model
Erdoğan, Zeynep; Ünlüsoy, Yavuz Samim; Department of Mechanical Engineering (2009)
The main motivation of this study is the design of a control strategy for semi-active vehicle suspension systems to improve ride comfort for road vehicles. In order to achieve this objective, firstly the damping characteristics of Magnetorheological dampers will be reviewed. Then an appropriate semi-active control strategy manipulating the inputs of the dampers to create suitable damping forces will be designed. Linear Quadratic Regulator (LQR) control strategy is the primary focus area on semi-active contr...
Analysis of high-g camera support structure for crash test system
Erdoğdu, Mahmut Gökhan; Gökler, Mustafa İlhan; Department of Mechanical Engineering (2009)
Sled Crash Test System is one of the key elements in todays high safety vehicle designs. In the crash test systems, high speed imaging by high speed cameras is required. For the success of high speed imaging, high speed cameras should be well secured on the sled of the system which is being accelerated to high-g values to simulate vehicle crash. In this study, structural analysis of the high – g camera support structure for the sled crash test sytem which is available in METU-BİLTİR Center Vehicle Safety Un...
Citation Formats
F. Sağlam, “Identification of low order vehicle handling models from multibody vehicle dynamics models,” M.S. - Master of Science, Middle East Technical University, 2010.