- Title
- Optimization of the vehicle suspension systems for improved comfort levels and advanced steering properties
- Creator
- Kuznetsov, Alexey
- Date
- 2011
- Type
- Text; Thesis
- Identifier
- http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/62065
- Identifier
- vital:4609
- Abstract
- There is a considerable body of research on the modelling and optimization of vehicle suspension systems. The main focus in most publications is an optimization procedure undertaken to find the values of the model parameters that satisfy certain operating requirements. However, the methods proposed do not always offer a broad variety of concepts and techniques. Most of these methods aim to find optimal values of suspension system parameters with respect to some optimality criteria that are often not explicitly formulated. In addition, none of the reviewed works utilizes existing guidelines and standards, on the vibration exposure on humans, to formulate optimization criteria. This would produce more applicable results of industrial and commercial merit. It is also important to mention that only a limited number of works offered numerical examples where real road conditions are employed for the optimization procedure. The presented thesis is devoted to development of a methodology for the optimization of vehicle suspension systems on the basis of two criteria: the improved comfort levels and advanced steering properties. The developed methodology is applied to various Australian roads, including highways, city roads, and country roads. It consists of a few steps as detailed below. The first step features the construction of a mathematical model for the vibration analysis of the vehicle suspension system. In the thesis different types of the quarter-car models and different biomechanical models for the driver are considered. All models considered are described by the corresponding systems of linear differential equations. The second step is undertaken to construct criteria to evaluate the comfort levels for the driver and passengers. For this purpose, a criterion was adopted from the ISO 2631 (1997) standards to quantify the comfort levels during a ride. To utilize this criterion, the steady-state vibrations, obtained from the system Differential Equations for various excitation frequencies, have been combined via a novel mathematical approach undertaken to eliminate the need to include the time of exposure in the calculations. This will enhance the applicability of the proposed method and simplify its implementation. 3 The third step is devoted to constructing a criterion to quantify the steering properties of a vehicle. The developed formula, which is based on an engineering understanding of how wheel vibration impacts the force interaction between the wheel and road, is proposed for the first time in the current thesis. The formula will serve as a criterion for advanced handling performance of passenger vehicles. The final step is undertaken to formulate optimization problems for finding the suspension system parameters which ensure improved comfort levels as well as admissible steering performance for the vehicle. For the analysis, these two criteria were employed to construct multi-criteria optimization problems and also singlecriteria optimization problems that incorporate both criteria. The developed methodology for the optimization of vehicle suspension systems is tested in a number of numerical examples using power spectral densities of several highways, city roads and country roads in Australia. Thus, it allows to offer recommendations for the optimal tuning of vehicle suspension systems taking into account real road conditions, steering performances and ISO 2631 (1997) standards for comfort levels.; Professional Doctorate
- Publisher
- University of Ballarat
- Rights
- Open Access
- Rights
- This metadata is freely available under a CCO license
- Subject
- Springs and suspension; Automobiles
- Full Text
- Hits: 722
- Visitors: 870
- Downloads: 225
| Thumbnail | File | Description | Size | Format | |||
|---|---|---|---|---|---|---|---|
| View Details Download | SOURCE1 | Australian Digital Thesis | 2 MB | Adobe Acrobat PDF | View Details Download |