Development and application of vehicle dynamics and control utilizng multibody vehicle models in native motionsim software and simulink
The goal of modeling and simulation of complex mechanical systems is to be able to predict the motion, response, forces and overall behavior of the systems. Through analysis of these predictions, the overall design objectives can be evaluated and optimized. Simulated multibody models can provide increased fidelity by including complexity and non-linear behavior with an increased number of elements, bodies, and joints that can be computed at once. Main contribution of this work is the development of native MotionSim set of codes, in Matlab, which allows generic modeling of any number of multibody systems. Joints, bodies and dynamic elements can be modeled in a simple way without restriction that other solvers may have due to choice of coordinates. MotionSim has the advantage of taking direct input of modeling parameters without additional CAD like modeling required in most commercial multibody software. Force elements and direct manipulation of the solver inputs allow high customization of the solution. This developed code is released to the public to be used freely. Vehicle dynamics is explored in this study as a topic from simple analytical models to large full-scale vehicle models to demonstrate the capabilities of MotionSim software in real world situations. Breakdowns of the vehicle characteristics and terminology typically used in describing vehicle models are provided. More complex models are developed and presented including visualization of Ackermann steering, inclusion of tire models from neural networks and finally a full-sized spatial multibody vehicle model. Simulink environment is utilized to addition of control for vehicle dynamics simulations. The methods and tools developed in this study allow mechanical systems design and vehicle engineers to model, simulate, control, and conduct parametric studies on complex vehicle systems in an efficient, cost effective, and simplified manner.
Networked Digital Library of Theses and Dissertations