Optimization And Control Of Semi Active Suspension System For Off Road Vehicles

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Optimization and Control of Semi-active Suspension System for Off-road Vehicles

Author : Ben Lahcene Zohir
Publisher :
ISBN 13 :
Total Pages : 412 pages
Book Rating : 4.:/5 (957 download)

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Book Synopsis Optimization and Control of Semi-active Suspension System for Off-road Vehicles by : Ben Lahcene Zohir

Download or read book Optimization and Control of Semi-active Suspension System for Off-road Vehicles written by Ben Lahcene Zohir and published by . This book was released on 2014 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study evaluates the dynamic response of three semi-active control policies as analyzed on a several off-road models. Two-axle 7DOF, three-axle 9DOF and four-axle 11DOF full vehicle system was developed to evaluate skyhook, groundhook, and hybrid controls. As well as exploring the relative benefits of each of these controllers, the performance of each semi-active controller was compared to the performance of conventional passive system. Each control policy is evaluated for its control performance under three different base excitations: step, bump and random. Corresponding to the bump and random inputs, peak-to-peak, RMS and frequency responses are considered for each control policy along with passive system. Specifically, sprung mass (heavy, pitch and roll acceleration), suspension and tire deflection. A comparison between different suspension systems were examined using half vehicle model and step input used to generate the time domain values of settling time and PTP acceleration for hybrid control policy and compared to fully active and passive systems using two-axle half vehicle model. Furthermore, Due to the importance of ride comfort for off-road vehicles, minimizing the peak-to-peak of the vertical, pitch and roll acceleration and reducing the settling time would lead to better ride comfort. In solving this problem, the step input was used for the optimization of a two-axle full vehicle's semi-active suspension system parameters with respect to ride comfort and handling. Genetic algorithm optimization technique is developed and used. Step input also used to generate the time domain and frequency domain responses of the four-axle full vehicle model. Reponses of sprung mass, suspension and tired deflection are obtained. Results of this study show that semi-active control offers benefits beyond those of conventional passive system. Further, traditional skyhook control is shown to be better in improving the vehicle body acceleration PTP, RMS and PSD responses. The groundhook control is shown to be better in controlling the tire deflection. Hybrid as a combination of both control policies skyhook and groundhook, shows to be better compromise in improving ride comfort and handling of the vehicle compared to passive system in all cases. Result shows also, that GA has consistently found near-optimal solutions within specified parameters ranges for several independent runs. Ride comfort improved without reducing the handling of the vehicle.

Semi-Active Suspension Control Design for Vehicles

Author : Sergio M. Savaresi
Publisher : Elsevier
ISBN 13 : 0080966799
Total Pages : 241 pages
Book Rating : 4.0/5 (89 download)

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Book Synopsis Semi-Active Suspension Control Design for Vehicles by : Sergio M. Savaresi

Download or read book Semi-Active Suspension Control Design for Vehicles written by Sergio M. Savaresi and published by Elsevier. This book was released on 2010-08-13 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semi-Active Suspension Control Design for Vehicles presents a comprehensive discussion of designing control algorithms for semi-active suspensions. It also covers performance analysis and control design. The book evaluates approaches to different control theories, and it includes methods needed for analyzing and evaluating suspension performances, while identifying optimal performance bounds. The structure of the book follows a classical path of control-system design; it discusses the actuator or the variable-damping shock absorber, models and technologies. It also models and discusses the vehicle that is equipped with semi-active dampers, and the control algorithms. The text can be viewed at three different levels: tutorial for novices and students; application-oriented for engineers and practitioners; and methodology-oriented for researchers. The book is divided into two parts. The first part includes chapters 2 to 6, in which fundamentals of modeling and semi-active control design are discussed. The second part includes chapters 6 to 8, which cover research-oriented solutions and case studies. The text is a comprehensive reference book for research engineers working on ground vehicle systems; automotive and design engineers working on suspension systems; control engineers; and graduate students in control theory and ground vehicle systems. Appropriate as a tutorial for students in automotive systems, an application-oriented reference for engineers, and a control design-oriented text for researchers that introduces semi-active suspension theory and practice Includes explanations of two innovative semi-active suspension strategies to enhance either comfort or road-holding performance, with complete analyses of both Also features a case study showing complete implementation of all the presented strategies and summary descriptions of classical control algorithms for controlled dampers

Semi-active Suspension Control

Author : Emanuele Guglielmino
Publisher : Springer Science & Business Media
ISBN 13 : 1848002319
Total Pages : 302 pages
Book Rating : 4.8/5 (48 download)

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Book Synopsis Semi-active Suspension Control by : Emanuele Guglielmino

Download or read book Semi-active Suspension Control written by Emanuele Guglielmino and published by Springer Science & Business Media. This book was released on 2008-05-27 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semi-active Suspension Control provides an overview of vehicle ride control employing smart semi-active damping systems. These systems are able to tune the amount of damping in response to measured vehicle-ride and handling indicators. Two physically different dampers (magnetorheological and controlled-friction) are analysed from the perspectives of mechatronics and control. Ride comfort, road holding, road damage and human-body modelling are studied. Mathematical modelling is balanced by a large and detailed section on experimental implementation, where a variety of automotive applications are described offering a well-rounded view. The implementation of control algorithms with regard to real-life engineering constraints is emphasised. The applications described include semi-active suspensions for a saloon car, seat suspensions for vehicles not equipped with a primary suspension, and control of heavy-vehicle dynamic-tyre loads to reduce road damage and improve handling.

Novel Semi-active Suspension with Tunable Stiffness and Damping Characteristics

Author : Adrian Louis Kuo-Tian Wong
Publisher :
ISBN 13 :
Total Pages : 92 pages
Book Rating : 4.:/5 (835 download)

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Book Synopsis Novel Semi-active Suspension with Tunable Stiffness and Damping Characteristics by : Adrian Louis Kuo-Tian Wong

Download or read book Novel Semi-active Suspension with Tunable Stiffness and Damping Characteristics written by Adrian Louis Kuo-Tian Wong and published by . This book was released on 2012 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the past several decades there have been many attempts to improve suspension performance due to its importance within vehicle dynamics. The suspension system main functions are to connect the chassis to the ground, and to isolate the chassis from the ground. To improve upon these two functions, large amounts of effort are focused on two elements that form the building blocks of the suspension system, stiffness and damping. With the advent of new technologies, such as variable dampers, and powerful microprocessors and sensors, suspension performance can be enhanced beyond the traditional capabilities of a passive suspension system. Recently, Yin et al. [1, 2] have developed a novel dual chamber pneumatic spring that can provide tunable stiffness characteristics, which is rare compared to the sea of tunable dampers. The purpose of this thesis is to develop a controller to take advantage of the novel pneumatic spring's functionality with a tunable damper to improve vehicle dynamic performance. Since the pneumatic spring is a slow-acting element (i.e. low bandwidth), the typical control logic for semi-active suspension systems are not practical for this framework. Most semi-active controllers assume the use of fast-acting (i.e. high bandwidth) variable dampers within the suspension design. In this case, a lookup table controller is used to manage the stiffness and damping properties for a wide range of operating conditions. To determine the optimum stiffness and damping properties, optimization is employed. Four objective functions are used to quantify vehicle performance; ride comfort, rattle space (i.e. suspension deflection), handling (i.e. tire deflection), and undamped sprung mass natural frequency. The goal is to minimize the first three objectives, while maximizing the latter to avoid motion sickness starting from 1Hz and downward. However, these goals cannot be attained simultaneously, necessitating compromises between them. Using the optimization strength of genetic algorithms, a Pareto optima set can be generated to determine the compromises between objective functions that have been normalized. Using a trade-off study, the stiffness and damping properties can be selected from the Pareto optima set for suitability within an operating condition of the control logic. When implementing the lookup table controller, a practical method is employed to recognize the road profile as there is no direct method to determine road profile. To determine the road profile for the lookup table controller, the unsprung mass RMS acceleration and suspension state are utilized. To alleviate the inherent flip-flopping drawback of lookup table controllers, a temporal deadband is employed to eliminate the flip-flopping of the lookup table controller. Results from the semi-active suspension with tunable stiffness and damping show that vehicle performance, depending on road roughness and vehicle speed, can improve up to 18% over passive suspension systems. Since the controller does not constantly adjust the damping properties, cost and reliability may increase over traditional semi-active suspension systems. The flip-flopping drawback of lookup table controllers has been reduced through the use of a temporal deadband, however further enhancement is required to eliminate flip-flopping within the control logic. Looking forward, the novel semi-active suspension has great potential to improve vehicle dynamic performance especially for heavy vehicles that have large sprung mass variation, but to increase robustness the following should be considered: better road profile recognition, the elimination of flip-flopping between suspension states, and using state equations model of the pneumatic spring within the vehicle model for optimization and evaluation.

Advanced Control for Vehicle Active Suspension Systems

Author : Weichao Sun
Publisher : Springer
ISBN 13 : 3030157857
Total Pages : 231 pages
Book Rating : 4.0/5 (31 download)

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Book Synopsis Advanced Control for Vehicle Active Suspension Systems by : Weichao Sun

Download or read book Advanced Control for Vehicle Active Suspension Systems written by Weichao Sun and published by Springer. This book was released on 2019-03-13 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on most recent theoretical findings on control issues for active suspension systems. The authors first introduce the theoretical background of active suspension control, then present constrained H∞ control approaches of active suspension systems in the entire frequency domain, focusing on the state feedback and dynamic output feedback controller in the finite frequency domain which people are most sensitive to. The book also contains nonlinear constrained tracking control via terminal sliding-mode control and adaptive robust theory, presenting controller design of active suspensions as well as the reliability control of active suspension systems. The target audience primarily comprises research experts in control theory, but the book may also be beneficial for graduate students alike.

Road and Off-Road Vehicle System Dynamics Handbook

Author : Gianpiero Mastinu
Publisher : CRC Press
ISBN 13 : 1420004905
Total Pages : 1678 pages
Book Rating : 4.4/5 (2 download)

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Book Synopsis Road and Off-Road Vehicle System Dynamics Handbook by : Gianpiero Mastinu

Off-road Vehicle Dynamics

Author : Hamid Taghavifar
Publisher : Springer
ISBN 13 : 331942520X
Total Pages : 191 pages
Book Rating : 4.3/5 (194 download)

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Book Synopsis Off-road Vehicle Dynamics by : Hamid Taghavifar

Download or read book Off-road Vehicle Dynamics written by Hamid Taghavifar and published by Springer. This book was released on 2016-07-27 with total page 191 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with the analysis of off-road vehicle dynamics from kinetics and kinematics perspectives and the performance of vehicle traversing over rough and irregular terrain. The authors consider the wheel performance, soil-tire interactions and their interface, tractive performance of the vehicle, ride comfort, stability over maneuvering, transient and steady state conditions of the vehicle traversing, modeling the aforementioned aspects and optimization from energetic and vehicle mobility perspectives. This book brings novel figures for the transient dynamics and original wheel terrain dynamics at on-the-go condition.

Dynamic and Control Analysis of Semi-Active Suspension System

Author : Zohir Ben lahcene
Publisher : LAP Lambert Academic Publishing
ISBN 13 : 9783843366052
Total Pages : 188 pages
Book Rating : 4.3/5 (66 download)

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Book Synopsis Dynamic and Control Analysis of Semi-Active Suspension System by : Zohir Ben lahcene

Download or read book Dynamic and Control Analysis of Semi-Active Suspension System written by Zohir Ben lahcene and published by LAP Lambert Academic Publishing. This book was released on 2010-10 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vehicles handling and ride comfort are essential subject because these vehicles operate at different environments. Improving the comfortability enables the drivers to derive for a long time at critical situations with full activity. This work deals with dynamics and control policies analysis of semi-active suspension systems for off-road vehicles. Comprehensive comparison on three different configurations; 2-axle, 3-axle and 4-axle half-vehicle models were conducted to analyze the effect of using semi-active control policies. The application of several control policies of semi-active suspension system, namely skyhook; ground-hook and hybrid controls have been analyzed and compared with passive systems. Sprung mass acceleration, suspension deflection and tyre deflection responses were analyzed for measurements of ride quality and road handling. Analysis in frequency domain transfer function, time domain transient state and time domain steady state were conducted on each of the models.

Development of a Semi-active Intelligent Suspension System for Heavy Vehicles

Author : Nima Eslaminasab
Publisher :
ISBN 13 : 9780494432679
Total Pages : 162 pages
Book Rating : 4.4/5 (326 download)

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Book Synopsis Development of a Semi-active Intelligent Suspension System for Heavy Vehicles by : Nima Eslaminasab

Download or read book Development of a Semi-active Intelligent Suspension System for Heavy Vehicles written by Nima Eslaminasab and published by . This book was released on 2008 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the new advancements in the vibration control strategies and controllable actuator manufacturing, the semi-active actuators (dampers) are finding their way as an essential part of vibration isolators, particularly in vehicle suspension systems. This is attributed to the fact that in a semi-active system, the damping coefficients can be adjusted to improve ride comfort and road handling performances. The currently available semi-active damper technologies can be divided into two main groups. The first uses controllable electromagnetic valves. The second uses magnetorheological (MR) fluid to control the damping characteristics of the system. Leading automotive companies such as General Motors and Volvo have started to use semi-active actuators in the suspension systems of high-end automobiles, such as the Cadillac Seville and Corvette, to improve the handling and ride performance in the vehicle. But much more research and development is needed in design, fabrication, and control of semi-active suspension systems and many challenges must be overcome in this area. Particularly in the area of heavy vehicle systems, such as light armored vehicles, little related research has been done, and there exists no commercially available controllable damper suitable for the relatively high force and large displacement requirements of such application. As the first response to these requirements, this thesis describes the design and modeling of an in-house semi-active twin-tube shock absorber with an internal variable solenoid-actuated valve. A full-scale semi-active damper prototype is developed and the shock absorber is tested to produce the required forcing range. The test results are compared with results of the developed mathematical model. To gain a better understanding of the semi-active suspension controlled systems and evaluate the performance of those systems, using perturbation techniques this thesis provides a detailed nonlinear analysis of the semi-active systems and establishes the issue of nonlinearity in on-off semi-active controlled systems. Despite different semi-active control methods and the type of actuators used in a semi-active controlled system, one important practical aspect of all hydro-mechanical computer controlled systems is the response-time. The longest response-time is usually introduced by the actuator -in this case, controllable actuator - in the system. This study investigates the effect of response-time in a semi-active controlled suspension system using semi-active dampers. Numerical simulations and analytical techniques are deployed to investigate the issue. The performance of the system due to the response-time is then analyzed and discussed. Since the introduction of the semi-active control strategy, the challenge was to develop methods to effectively use the capabilities of semi-active devices. In this thesis, two semi-active control strategies are proposed. The first controller to be proposed is a new hybrid semi-active control strategy based on the conventional Rakheja-Sankar (R-S) semi-active control to provide better ride-handling quality for vehicle suspension systems as well as industrial vibration isolators. To demonstrate the effectiveness of this new strategy, the analytical method of averaging and the numerical analysis method are deployed. In addition, a one-degree-of-freedom test bed equipped with a semi-active magnetorheological (MR) damper is developed. The tests are performed using the MATLAB XPC-target to guarantee the real-time implementation of the control algorithm. The second controller is an intelligent fuzzy logic controller system to optimize the suspension performance. The results from this intelligent system are compared with those of several renowned suspension control methods such as Skyhook. It is shown that the proposed controller can enhance concurrently the vehicle handling and ride comfort, while consuming less energy than existing control methodologies. The key goal of this thesis is to employ the existing knowledge of the semi-active systems together with the new ideas to develop a semi-active suspension system. At the same time, development of an experimental simulation system for real-time control of an experimental test bed is considered. To achieve its goals and objectives, this research study combines and utilizes the numerical simulations and analytical methods, as well as lab-based experimental works. The challenge in this research study is to identify practical and industrial problems and develop proper solutions to those problems using viable scientific approaches.

A Methodology for Optimizing Semi-active Suspensions for Automotive Applications

Author : Hongtei Eric Tseng
Publisher :
ISBN 13 :
Total Pages : 430 pages
Book Rating : 4.:/5 (33 download)

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Book Synopsis A Methodology for Optimizing Semi-active Suspensions for Automotive Applications by : Hongtei Eric Tseng

Download or read book A Methodology for Optimizing Semi-active Suspensions for Automotive Applications written by Hongtei Eric Tseng and published by . This book was released on 1994 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Road and Off-Road Vehicle System Dynamics Handbook

Author : Gianpiero Mastinu
Publisher : CRC Press
ISBN 13 : 0849333229
Total Pages : 1710 pages
Book Rating : 4.8/5 (493 download)

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Book Synopsis Road and Off-Road Vehicle System Dynamics Handbook by : Gianpiero Mastinu

Download or read book Road and Off-Road Vehicle System Dynamics Handbook written by Gianpiero Mastinu and published by CRC Press. This book was released on 2014-01-06 with total page 1710 pages. Available in PDF, EPUB and Kindle. Book excerpt: Featuring contributions from leading experts, the Road and Off-Road Vehicle System Dynamics Handbook provides comprehensive, authoritative coverage of all the major issues involved in road vehicle dynamic behavior. While the focus is on automobiles, this book also highlights motorcycles, heavy commercial vehicles, and off-road vehicles. The authors of the individual chapters, both from automotive industry and universities, address basic issues, but also include references to significant papers for further reading. Thus the handbook is devoted both to the beginner, wishing to acquire basic knowledge on a specific topic, and to the experienced engineer or scientist, wishing to have up-to-date information on a particular subject. It can also be used as a textbook for master courses at universities. The handbook begins with a short history of road and off-road vehicle dynamics followed by detailed, state-of-the-art chapters on modeling, analysis and optimization in vehicle system dynamics, vehicle concepts and aerodynamics, pneumatic tires and contact wheel-road/off-road, modeling vehicle subsystems, vehicle dynamics and active safety, man-vehicle interaction, intelligent vehicle systems, and road accident reconstruction and passive safety. Provides extensive coverage of modeling, simulation, and analysis techniques Surveys all vehicle subsystems from a vehicle dynamics point of view Focuses on pneumatic tires and contact wheel-road/off-road Discusses intelligent vehicle systems technologies and active safety Considers safety factors and accident reconstruction procedures Includes chapters written by leading experts from all over the world This text provides an applicable source of information for all people interested in a deeper understanding of road vehicle dynamics and related problems.

Comparisons of Active, Passive and Semi-active Suspensions for Ground Vehicles

Author : Pipon Boonchanta
Publisher :
ISBN 13 :
Total Pages : 468 pages
Book Rating : 4.:/5 (15 download)

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Book Synopsis Comparisons of Active, Passive and Semi-active Suspensions for Ground Vehicles by : Pipon Boonchanta

Download or read book Comparisons of Active, Passive and Semi-active Suspensions for Ground Vehicles written by Pipon Boonchanta and published by . This book was released on 1981 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Dynamics and Control Policies Analysis of Semi-active Suspension System for Off-road Vehicle

Author : Zohir Benlahcene
Publisher :
ISBN 13 :
Total Pages : 312 pages
Book Rating : 4.:/5 (957 download)

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Book Synopsis Dynamics and Control Policies Analysis of Semi-active Suspension System for Off-road Vehicle by : Zohir Benlahcene

Download or read book Dynamics and Control Policies Analysis of Semi-active Suspension System for Off-road Vehicle written by Zohir Benlahcene and published by . This book was released on 2009 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:

High Speed Off-Road Vehicles

Author : Bruce Maclaurin
Publisher : John Wiley & Sons
ISBN 13 : 1119258782
Total Pages : 277 pages
Book Rating : 4.1/5 (192 download)

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Book Synopsis High Speed Off-Road Vehicles by : Bruce Maclaurin

Download or read book High Speed Off-Road Vehicles written by Bruce Maclaurin and published by John Wiley & Sons. This book was released on 2018-09-17 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: A concise reference that provides an overview of the design of high speed off-road vehicles High Speed Off-Road Vehicles is an excellent, in-depth review of vehicle performance in off-road conditions with a focus on key elements of the running gear systems of vehicles. In particular, elements such as suspension systems, wheels, tyres, and tracks are addressed in-depth. It is a well-written text that provides a pragmatic discussion of off-road vehicles from both a historical and analytical perspective. Some of the unique topics addressed in this book include link and flexible tracks, ride performance of tracked vehicles, and active and semi-active suspension systems for both armoured and unarmoured vehicles. The book provides spreadsheet-based analytic approaches to model these topic areas giving insight into steering, handling, and overall performance of both tracked and wheeled systems. The author further extends these analyses to soft soil scenarios and thoroughly addresses rollover situations. The text also provides some insight into more advanced articulated systems. High Speed Off-Road Vehicles: Suspensions, Tracks, Wheels and Dynamics provides valuable coverage of: Tracked and wheeled vehicles Suspension component design and characteristics, vehicle ride performance, link track component design and characteristics, flexible track, and testing of active suspension test vehicles General vehicle configurations for combat and logistic vehicles, suspension performance modelling and measurement, steering performance, and the effects of limited slip differentials on the soft soil traction and steering behavior of vehicles Written from a very practical perspective, and based on the author’s extensive experience, High Speed Off-Road Vehicles provides an excellent introduction to off-road vehicles and will be a helpful reference text for those practicing design and analysis of such systems.

Vibration Control of Vehicle Suspension Systems

Author : Haiping Du
Publisher : CRC Press
ISBN 13 : 1000999297
Total Pages : 323 pages
Book Rating : 4.0/5 (9 download)

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Book Synopsis Vibration Control of Vehicle Suspension Systems by : Haiping Du

Download or read book Vibration Control of Vehicle Suspension Systems written by Haiping Du and published by CRC Press. This book was released on 2023-12-18 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers complex issues for a vehicle suspension model, including non-linearities and uncertainties in a suspension model, network-induced time delays, and sampled-data model from a theoretical point of view. It includes control design methods such as neural network supervisory, sliding mode variable structure, optimal control, internal-model principle, feedback linearization control, input-to-state stabilization, and so on. Every control method is applied to the simulation for comparison and verification. Features: Includes theoretical derivation, proof, and simulation verification combined with suspension models Provides the vibration control strategies for sampled-data suspension models Focuses on the suspensions with time-delays instead of delay-free Covers all the models related to quarter-, half-, and full-vehicle suspensions Details rigorous mathematical derivation process for each theorem supported by MATLAB®-based simulation This book is aimed at researchers and graduate students in automotive engineering, vehicle vibration, mechatronics, control systems, applied mechanics, and vehicle dynamics.

Efficient Gradient-based Optimisation of Suspension Characteristics for an Off-road Vehicle

Author : Michael John Thoresson
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (956 download)

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Book Synopsis Efficient Gradient-based Optimisation of Suspension Characteristics for an Off-road Vehicle by : Michael John Thoresson

Download or read book Efficient Gradient-based Optimisation of Suspension Characteristics for an Off-road Vehicle written by Michael John Thoresson and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The efficient optimisation of vehicle suspension systems is of increasing interest for vehicle manufacturers. The main aim of this thesis is to develop a methodology for efficiently optimising an off-road vehicle's suspension for both ride comfort and handling, using gradient based optimisation. Good ride comfort of a vehicle traditionally requires a soft suspension setup, while good handling requires a hard suspension setup. The suspension system being optimised is a semi-active suspension system that has the ability to switch between a ride comfort and a handling setting. This optimisation is performed using the gradient-based optimisation algorithm Dynamic-Q. In order to perform the optimisation, the vehicle had to be accurately modelled in a multi-body dynamics package. This model, although very accurate, exhibited a high degree of non-linearity, resulting in a computationally expensive model that exhibited severe numerical noise. In order to perform handling optimisation, a novel closed loop driver model was developed that made use of the Magic Formula to describe the gain parameter for the single point driver model's steering gain. This non-linear gain allowed the successful implementation of a single point preview driver model for the closed loop double lane change manoeuvre, close to the vehicle's handling limit. Due to the high levels of numerical noise present in the simulation model's objective and constraint functions, the use of central finite differencing for the determination of gradient information was investigated, and found to improve the optimisation convergence history. The full simulation model, however, had to be used for the determination of this gradient information, making the optimisation process prohibitively expensive, when many design variables are considered. The use of carefully chosen simplified two-dimensional non-linear models were investigated for the determination of this gradient information. It was found that this substantially reduced the total number of expensive full simulation evaluations required, thereby speeding up the optimisation time. It was, however, found that as more design variables were considered, some variables exhibited a lower level of sensitivity than the other design variables resulting in the optimisation algorithm terminating at sub-optimal points in the design space. A novel automatic scaling procedure is proposed for scaling the design variables when Dynamic-Q is used. This scaling methodology attempts to make the n-dimensional design space more spherical in nature, ensuring the better performance of Dynamic-Q, which makes spherical approximations of the optimisation problem at each iteration step. The results of this study indicate that gradient-based mathematical optimisation methods may indeed be successfully integrated with a multibody dynamics analysis computer program for the optimisation of a vehicle's suspension system. Methods for avoiding the negative effects of numerical noise in the optimisation process have been proposed and successfully implemented, resulting in an improved methodology for gradient-based optimisation of vehicle suspension systems.

Vehicle Suspension Systems and Electromagnetic Dampers

Author : Saad Kashem
Publisher : Springer
ISBN 13 : 9811054789
Total Pages : 218 pages
Book Rating : 4.8/5 (11 download)

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Book Synopsis Vehicle Suspension Systems and Electromagnetic Dampers by : Saad Kashem

Download or read book Vehicle Suspension Systems and Electromagnetic Dampers written by Saad Kashem and published by Springer. This book was released on 2017-09-04 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the development of a new analytical, full-vehicle model with nine degrees of freedom, which uses the new modified skyhook strategy (SKDT) to control the full-vehicle vibration problem. The book addresses the incorporation of road bank angle to create a zero steady-state torque requirement when designing the direct tilt control and the dynamic model of the full car model. It also highlights the potential of the SKDT suspension system to improve cornering performance and paves the way for future work on the vehicle’s integrated chassis control system. Active tilting technology to improve vehicle cornering is the focus of numerous ongoing research projects, but these don’t consider the effect of road bank angle in the control system design or in the dynamic model of the tilting standard passenger vehicles. The non-incorporation of road bank angle creates a non-zero steady state torque requirement.