<p> The objective of this research is to develop an integrated system engineering methodology for the customization design to maximize vehicle performance upgrade freedom while ensuring vehicle dynamics compliance.</p><p> A post-delivery modification framework, which is led by an aftermarket umbrella organization and involve various stakeholders has been established. The umbrella organization will be in charge of developing the design envelope and distribute to various aftermarket kit suppliers to generate specific products according to their brand essence.</p><p> A generic mathematical representation of a (proprietary) ESC system has been developed for virtual certification purposes. This approach is a cost-effective alternative to physical on-road testing and hardware-in-the-loop (HiL) simulations. Furthermore, based on the stability control model, the modification impacts on the vehicle dynamics and stability performance was assessed using the Taguchi design of experiment (DOE) method. DOE results provide three distinct ways for supporting aftermarket modifications. First, main effects help customizers to understand which modification bring benefits or risks. Second, a regression model of the lateral offset metrics helps suppliers to predict closed-loop performances with open-loop testing information which require much less time and cost. Finally, the pass/fail criteria regarding federally mandated ESC compliance (FMVSS 126) brought on the &lsquo;Pass Region&rsquo; which consisted of feasible configurations such that customizers may configure their options within a safe zone. Each of these methods complements others for supporting the aftermarket modification.</p><p> In order to improve the computation efficiency, two lower fidelity models were developed: A linear model and a surrogate model. The linear model is derived from the high fidelity model with reduced degrees of freedom (DOF) and linearized parameters. Tire cornering stiffness is treated as constants for gentle maneuvers, and varying parameters for high-dynamic driving maneuver. The linear system is either a linear time-invariant (LTI) system or a linear parameter-varying (LPV) system depending on the application context. The PD yaw stability control algorithm, which is inherited from the high fidelity model, was simplified but retained with critical nonlinear features. A quadratic regression model that was dedicated for compliance metrics was developed as a surrogate model incorporated in an interactive rule-based design envelope. </p><p> An interactive design envelope has been created incorporating the rules established using computational efficient linear and surrogate models. The constraint satisfaction problem is described in the nonlinear programming context and solved using sequential quadratic programming. The quasiconvexity of the design space, which is the necessary condition for the proposed approach, is also investigated by inspecting the constraint functions. Finally, two case studies were developed to demonstrate the framework developed which was validated against the high fidelity co-simulation model.</p>

<p>Automotive manufacturers face interesting challenges as electronic devices are becoming essential in modern vehicles. Therefore new approaches and strategies are to be adopted in order to tackle the coming challenges. One of the most rapidly growing domains is infotainment and telematics, where applications require a large amount of data to be transmitted on-board and also exchanged with the external world. The in-vehicle communication networks for infotainment systems must consequently be devised considering the need for transporting the considerable amount of data of multimedia applications as well as features particular to this area.</p><p>This thesis is intended to analyze possible implementations of multimedia networks for heavy transport vehicles, in relation to various aspects and features in this area. The thesis presents an analysis of different protocols and technologies used in automotive multimedia networks. Furthermore, characteristic requirements for automotive electronics systems and especially for automotive multimedia networks are investigated in detail. Based on these requirements different multimedia networks are proposed and studied, making a comparison between them with regard to a number of criteria.</p><p>A broad approach during the investigation of the multimedia protocols is chosen in order to enlarge the area of used technology and to bring new technologies and possibilities for the truck industry. The observations and the experiences from the car industry are used in the truck domain, where the specifics of the truck industry are taken into account. The comparison gives an insight into the particulars of the proposed solutions from several viewpoints so that a suitable multimedia network can be selected based on different criteria.</p>

Automotive manufacturers face interesting challenges as electronic devices are becoming essential in modern vehicles. Therefore new approaches and strategies are to be adopted in order to tackle the coming challenges. One of the most rapidly growing domains is infotainment and telematics, where applications require a large amount of data to be transmitted on-board and also exchanged with the external world. The in-vehicle communication networks for infotainment systems must consequently be devised considering the need for transporting the considerable amount of data of multimedia applications as well as features particular to this area. This thesis is intended to analyze possible implementations of multimedia networks for heavy transport vehicles, in relation to various aspects and features in this area. The thesis presents an analysis of different protocols and technologies used in automotive multimedia networks. Furthermore, characteristic requirements for automotive electronics systems and especially for automotive multimedia networks are investigated in detail. Based on these requirements different multimedia networks are proposed and studied, making a comparison between them with regard to a number of criteria. A broad approach during the investigation of the multimedia protocols is chosen in order to enlarge the area of used technology and to bring new technologies and possibilities for the truck industry. The observations and the experiences from the car industry are used in the truck domain, where the specifics of the truck industry are taken into account. The comparison gives an insight into the particulars of the proposed solutions from several viewpoints so that a suitable multimedia network can be selected based on different criteria.

Thesis (M.S.)--Ohio State University, 1967. / Available online via OhioLINK's ETD Center

In an effort to improve the safety and road-holding capabilities of vehicles, manufacturers have begun a trend toward increasing vehicle body roll resistance by introducing stiffer roll-stabilizer bars. In this study vehicle suspension and road surface models are developed to investigate the effects of such stabilizer bars on ride quality. The purpose of the research is to determine the need for further studies in the area of active roll stabilizer systems. Two dynamic vehicle models are developed: the simplified front-car model and the full-vehicle-body three-degree-of-freedom model. The effects of the stabilizer bars on ride quality are then studied through the use of asymmetric road surface profiles. Discrete, periodic, and random road surface models are used to excite the vehicle models. Emphasis is placed on random road models and predicting the vehicle response using spectral input/output techniques.

<p> This dissertation describes a methodology for the vehicle dynamics control of a wheel motored vehicle. All theory is developed assuming that the driver has control of the front wheel steering angle, and that wheel torque is solely generated by independent wheel motors at each corner of the vehicle. Theoretical work is presented for the general case with four independent wheel motors, but can be easily reduced to a situation with only two wheel motors. Indeed, all theory developed in this work is evaluated experimentally on a production automobile converted to be driven by two independent rear wheel motors. </p><p> As opposed to directly allocating wheel torques, the proposed philosophy operates in the slip-ratio domain. Doing so helps to prevent excessive tire saturation and allows the system to adapt to changing road surfaces. To that end, this dissertation first proposes a method of estimating slip-ratio utilizing only sensors currently available on modern automobiles. A slip-ratio controller is then developed approximating the disturbance observer structure. This allows the controller to be robust to changing road surface and as a byproduct provide an accurate estimate of longitudinal tire force. Combining the estimated longitudinal tire force with the estimated slip-ratio it is then possible to ascertain some degree of tire saturation. With this in mind, an optimal control allocation problem is proposed which attempts to achieve the desired vehicle dynamics while at the same time minimizing tire saturation. </p><p> It is shown experimentally that the proposed control methodology effectively achieves desired vehicle dynamics. In addition, the system adapts its behavior to changing road surfaces resulting in optimal performance regardless of operating conditions.</p>

Innovative clutching mechanisms for hybrid automotive transmissions that yield low losses, while still satisfying the conflicting requirements of compactness, quick response, and high power density are explored in this thesis. Moreover, a systematic approach to automotive-transmission clutch design is proposed. The goal is to provide a complementary tool to aid the designer's judgment. The various design variants chosen serve two purposes, to demonstrate the foundation and to showcase approaches and solutions to specific problems that have a direct application in transmission design. The analysis of design variants goes into sufficient depth to be useful to both practicing automotive design engineers and academics.The phenomenon of "spin loss" is well known in the automotive industry, for it affects all transmissions. One energy sink identified in this regard lies in traditional wet clutches and brakes, wherein an open clutch or, correspondingly, an open brake, creates drag on the transmission because of the oil churning around and between the rotating friction plates. A second source of spin loss, or energy sink, is of electromagnetic origin, as it occurs by virtue of spinning inactive motors that carry permanent magnets. Apart from spin losses, the hydraulic actuation of clutches and brakes suffers from head losses. Seals, pumps and valves incur leakages that cause energy loss.Using the techniques outlined in this thesis, two separate novel clutch variants are demonstrated to improve clutch and brake technology. One variant, the electromechanical clutch actuator, is based on a high-performance screw joint with a built-in locking mechanism. The screw joint was tested with two sub-variants, namely, a lead screw and a ball screw. One prototype of each of the two sub-variants was installed on a testbed, to mimic the installation of the actuator in place of the corresponding hydraulic components. To better reflect the elastostatic behaviour of the clutch disk assembly, a new model for its stiffness as a hardening spring was formulated. Proof-of-concept tests of both sub-variants, lead and ball screws, demonstrated their feasibility.The second variant, the electromagnetic dog clutch, is directly aimed at minimizing spin and hydraulic actuation losses for clutched electric motors, wherein the motor is connected to a clutch. The system includes a unique contactless electromagnetic synchronizer and a synchronizing sleeve with dog teeth on the input and output components. The design study, focused on the electromagnetic part, strives to reduce clutch slip and control torque. The novel design features claw-like stator and salient rotor poles with good machinability within a restrictive design volume. A complete design analysis with physical proof-of-concept testing was conducted.Reducing "spin-loss" in transmission assemblies will improve system efficiency and yield better fuel economy. The technologicalimpact will benefit not only the user, who will obtain more mileage for her or his dollar, but also the environment. / Dans cette thèse sont étudiés des mécanismes innovants d'embrayage pour transmissions automobiles hybrides qui n'engendrent que de faibles pertes, tout en satisfaisant les besoins parfois conflictives de compacité, de haute vitesse de réaction et de haute densité d'énergie. Une approche systématique de la conception de transmissions automobiles est proposée, dont l'objectif est d'offrir un outil complémentaire au jugement du concepteur. Les divers alternatives choisises servent à présenter les concepts fondamentaux, ainsi qu'à mettre en valeur les différentes approches et solutions à des problèmes spécifiques qui ont une application directe dans le domaine des conceptions de transmissions. L'analyse d'alternatives de conception va suffisamment en profondeur pour être utile à la fois aux ingénieurs de conception automobile et aux théoriciens.Le phénomène de pertes d'énergie cinétique de rotation (PECR) est bien connu dans l'industrie automobile, car cela affecte toutes les transmissions. Un puits d'énergie mis en évidence à ce propos concerne les embrayages et freins traditionnels à fluides, pour lesquels un embrayage ouvert ou un frein ouvert, crée une traînée dans la transmission parce que l'huile tourbillonne autour et dans les plaques tournantes de friction. Un second puits d'énergie est d'origine électromagnétique, car générée par la rotation de moteurs inactifs contenant des aimants permanents. Hormis le PECR, l'actionnement hydraulique d'embrayages ou de freins entraîne des pertes de charges. Les joints, pompes et valves encourent des fuites qui engendrent de puits d'énergie.En utilisant les techniques mises en avant dans cette thèse, deux nouvelles alternatives d'embrayages démontrent leurs capacités à améliorer les technologies des freins et des embrayages. L'une de ces alternatives, l'actionneur {\em électromécanique d'embrayage}, est basée sur une liaison à vis et dispose d'un mécanisme intégré de verrouillage. La liaison à vis a été testée au travers de deux sous-alternatives, à savoir une vis à filet trapézoïdal et une vis à billes. Un prototype de chacune des alternatives a été installé sur un banc d'essai, afin de reproduire l'installation de l'actionneur en lieu et place des composants hydrauliques correspondants. Pour mieux refléter le comportement élastostatique de l'assemblage des disques d'embrayage, un nouveau modèle de sa raideur, assimilée à un ressort durcissant, a été formulé. Des tests de preuve de concept des deux variantes, vis à filet trapézoïdal et vis à billes, ont montré leur faisabilité.La seconde variante, l'embrayage électromagnétique à interférence, est directement utilisable pour minimiser les pertes en rotation et en actionnement hydraulique pour les moteurs électriques à embrayage, pour lesquels un moteur est connecté à un embrayage. Le système inclut un unique synchronisateur et des bagues de synchronisation avec des dents-de-chien sur les composants en entrée et en sortie. Le travail de conception a été concentré sur la partie électromagnétique, qui essaie de réduire le glissement de l'embrayage et le couple de commande. Le nouveau système conception est doté d'un stator en forme de griffes et des pôles de rotor saillants faciles à usiner et à installer dans un espace restreint dans la voiture. Une étude complète de conception avec des tests concrets de preuve de concept a été accomplie.Rééduire le PECR dans les assemblages de transmissions améliorera l'efficience du système et mènera à davantage d'économie de carburant. L'impact technologique sera ainsi bénéfique non seulement pour l'utilisateur, qui profitera d'un kilométrage plus élevé pour son argent, mais aussi pour l'environnement.

Thesis (Ph.D.)--University of California, Davis, 2008. / Advisers: Daniel Sperling, Ken Kurani. Includes bibliographical references.

Thesis (Ph. D.)--Ohio State University, 1977. / Includes vita. Includes bibliographical references (v. 2, leaves 821-830). Available online via OhioLINK's ETD Center.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1983. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.