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Software programs in non-application areas such as Board Support Packages, Hardware Abstraction Layers, signal processing and data acquisition are more or less very standard and common across many applications. These form a major part of the “platform” software, which changes very little. However, it is seen that many a time, efforts are spent resolving issues in the hardware dependent layers rather than concentrating on the application at hand, despite the fact that the software controlling the hardware has been developed many times. There are many reasons why this section of the software is rewritten many times over: different coding standards, different software architecture and layering concepts, the dreadful cut-and-paste methods, and so on. Introduction of a tool-based code configurator and generator eliminates access to the code and focuses on configuring a pre-written set of SW procedures. Advantages: Standardization, reuse and high levels of productivity.

Vehicle dynamics is a discipline of mechanical engineering that benefited of significant improvements thanks to the progress of computational engineering. Vehicle dynamics engineers are using CAE for the development of a vehicle with MBS and FEA. The concurrent use of these two technologies is a standard in the automotive industry. However the current simulation process is not fully efficient because local geometrical and material nonlinearities are not accurately modeled in classical MBS software. This paper introduces a methodology for vehicle dynamics simulation integrating MBS capabilities in one single nonlinear FEA environment enabling an accurate modeling of nonlinearity in vehicles.

Buick engineers are well pleased with their '69 Chassis. Benefits of a unique front suspension camber curve are documented. The effects of various suspension parameters on ride and handling are explained. These were varied independently of one another in the course of evaluating over 30 suspension configurations.

THE usefulness of planetary gear trains and the engineering techniques necessary for optimum design are discussed in this paper. A simple method for calculating planetary gear ratios is described which can be used to determine quickly the potential usefulness of any planetary configurations. The author lists criteria which help to evaluate the potential of a planetary gear train schematic from the standpoints of gear noise and structural viewpoint. Detailed design of individual members include spacing of the pinions, mounting considerations, thrust direction, lubrication, and stress evaluation.

This paper sets up a simplified dynamic model for simulating the yaw/roll stability of heavy tractor-semitrailer using Matlab/Simulink. A linear quadratic regulator (LQR) based on partial-state feedback controller is used to optimize the roll stability of the vehicle. The control objective for optimizing roll stability is to be reducing the lateral load transfer rate while keeping the suspension angle less than the maximum allowable angle. The simulation result shows that the LQR controller is effective in the active roll stability control of the heavy tractor-semitrailer.

Two methods for calculating speed from curved tire marks were investigated. The commonly used critical speed formula and a computer simulation program were evaluated based on their ability to reproduce the results of full-scale yaw tests. The effects of vehicle braking and friction coefficient were studied. Twenty-two yaw tests were conducted at speeds between 70 and 120 km/h. For half of the tests, about 30% braking was applied. Using the measured sliding coefficient of friction, both the critical speed formula and the computer simulations under-predicted the actual speed of the vehicle. Using the measured peak coefficient of friction, both methods over-estimated the actual speed. There was less variance in the computer simulation results. Braking tended to increase the speeds calculated by the critical speed formula.

In this paper, a gain-scheduling optimal control approach is proposed to enhance yaw stability of articulated commercial vehicles through active braking of the proper wheel(s). For this purpose, an optimal feedback control is used to design a family of yaw moment controllers considering a broad range of vehicle velocities. The yaw moment controller is designed such that the instantaneous tractor yaw rate and articulation angle responses are forced to track the target values at each specific vehicle velocity. A gain scheduling mechanism is subsequently constructed via interpolations among the controllers. Furthermore, yaw moments derived from the proposed controller are realized by braking torque distribution among the appropriate wheels. The effectiveness of the proposed yaw stability control scheme is evaluated through software-in-the-loop (SIL) co-simulations involving Matlab/Simulink and TruckSim under lane change maneuvers.

In this paper a yaw stability control algorithm along with an emergency roll control strategy have been developed. The yaw stability controller and emergency roll controller were both developed using linear two degree-of-freedom vehicle models. The yaw stability controller is based on Lyapunov stability criteria and uses vehicle lateral acceleration and yaw rate measurements to calculate the corrective yaw moment required to stabilize the vehicle yaw motion. The corrective yaw moment is then applied by means of a differential braking strategy in which one wheel is selected to be braked with appropriate brake torque applied. The emergency roll control strategy is based on a rollover coefficient related to vehicle static stability factor. The emergency roll control strategy utilizes vehicle lateral acceleration measurements to calculate the roll coefficient. If the roll coefficient exceeds some predetermined threshold value the emergency roll control strategy will deploy.

From the beginning of 1995 on, RB will start the production of the Vehicle Dynamics Control System. A key part of this system is the Yaw Rate Sensor described in this paper. The basic requirements for this sensor for automotive applications are: mass producibility, low cost, resistance against environmental influences (such as temperature, vibrations, EMI), stability of all characteristics over life time, high reliability and designed-in safety. Bosch developed a sensor on the basis of the “Vibrating Cylinder”. The sensor will be introduced into mass production in beginning of 1995.

In the current Ford Pro-Trailer Backup Assist (TBA) system, trailer hitch angle is determined utilizing the reverse camera of the vehicle. In addition to being sensitive to environmental factors such as lighting conditions and occlusion, the vision-based approach is difficult to be applied to gooseneck or fifth wheel trailers. In this paper, a yaw rate based hitch angle observer is proposed as an alternative sensing solution for TBA. Based on the kinematic model of the vehicle-trailer, an instantaneous hitch angle is first derived by utilizing vehicle yaw rate, trailer yaw rate, vehicle velocity and vehicle/trailer parameters provided by the TBA system. Due to signal errors and parameter uncertainties, this instantaneous hitch angle may be noisy, especially at lower vehicle speed.

A new controllable limited slip differential is proposed and tested in software environment. It is characterized by the employment of a magnetorheological fluid, which presents the property of changing its rheology thanks to an applied magnetic field. A vehicle model has been designed and employed for the synthesis of a sliding controller. The control is based on a double level scheme: the upper controller aims to generate the target locking torque, while the lower controller generates, as control action, the supply current for the controllable limited slip differential. The obtained results show the effectiveness of the device in terms of vehicle dynamics improvement. Indeed, the results reached by the vehicle in presence of the new differential confirm the improved performances for both steady and unsteady state manoeuvres.

Active vehicle dynamics control ensures improved safety. So far, yaw instability is mostly associated with transient steering manoeuvres when driving at a constant speed. However, braking related load transfer affects yaw stability. Intense braking at high friction combined with elevated and forwarded CG amplifies this influence on unloaded tractors. Designing a dynamic stability system to enhance active safety requires fresh insight into braking related yaw instability. This investigation covers a theoretical analysis of braking influence on yaw stability on unloaded 4×2 tractors, being applicable to vehicle braking while cornering, including steering induced by other asymmetrical forces, since it focuses essentially on small steering angles.

This study presents results from x-ray analysis of live human head/neck motion in sled test simulations of low-speed frontal, lateral, and rear-end vehicle impacts. The test subjects were 26 male and female adults, aged 22 to 61 years. Head/neck motion and the kinematic responses of each test subject were measured and analyzed by cineradiograph, high-speed film, accelerometers, and electromyography of the neck muscles. The methodology used may provide insight into the mechanism of neck injuries caused by the head inertia loading. The actual kinematic responses of the head/neck were found to be more complex than previously thought. The experimental results suggest that the most significant factor of the head/neck response is the initial curvature of the cervical and thoracic spine. Looking specifically at the early motion of the head and neck in rear-end impacts, the cervical forward curvature (lordosis) and the thoracic rearward curvature (kyphosis) were found to straighten.

Radiographs were taken of the cervical spines of male subjects during voluntary motion from full flexion to full extension. Approximately 16 radiographs were taken during a period of 3 1/2 seconds. The resulting motions of the cervical vertebrae were analyzed. A simple pinned-link model of the spine under these conditions is presented.

Residual stress and hardness in steel due to thermal, mechanical, and fatigue deformations are determined by an X-ray diffraction method. The sharp temperature rise associated with electrical discharge machining causes austenitizing, rehardening, and tempering, and results in high tensile residual stress. Shot-peening quality is evaluated from residual stress and hardness induced by the peening. Rolling contact fatigue of carburized and hardened bearings causes a transformation of austenite to martensite, and thereby generates more residual compression, and also causes permanent fatigue softening. Less softening is observed in inner races of consutrode and cross-forged steels than in air-melted steel, and the former steels exhibit greater fatigue life at early and mean failure levels.

The current test methods are insufficient to evaluate and ensure the safety and reliability of vehicle system for all possible dynamic situations including the worst cases such as rollover, spin-out and so on. Although the known NHTSA J-turn and Fish-hook steering maneuvers are applied for the vehicle performance assessment, they are not enough to predict other possible worst case scenarios. Therefore, it is crucial to search for the various worst cases including the existing severe steering maneuvers. This paper includes the procedure to search for other useful worst case based upon the existing worst case scenarios in terms of rollover and its application in simulation basis. The human steering angle is selected as a design variable and optimized to maximize the index function to be expressed in terms of vehicle roll angle. The obtained scenarios were enough to generate the worse cases than NHTSA ones.

The results of biomechanical testing of the WorldSID prototype dummy are presented in this paper. The WorldSID dummy is a new, advanced Worldwide Side Impact Dummy that has the anthropometry of a mid-sized adult male. The first prototype of this dummy has been evaluated by the WorldSID Task Group against previously established corridors for its critical body regions. The response corridors are defined in the International Organization of Standardization (ISO) Technical Report 9790. The prototype is the first version of the WorldSID dummy to be built and tested. This dummy has been subjected to a rigorous program of testing to evaluate, first and foremost its biofidelity, but also its repeatability. Following this initial evaluation, any required modifications will be incorporated into a pre-production version of the WorldSID dummy so that it rates “good” to “excellent” on the ISO dummy biofidelity scale – a rating exceeding that of all current side impact dummies.

The WorldSID 5th percentile dummy, representing an average female, was developed in less than three years after the WorldSID 50th percentile dummy production release. This 5th percentile dummy was developed in the Integrated Project Aprosys (Advanced Protection Systems) under the European Commission Framework Program 6. This paper discusses the rationale for the WorldSID 5th percentile dummy design and development, and biofidelity evaluation results of head drop test, neck pendulum test and pendulum impact tests of the shoulder, thorax, abdomen and pelvis according to ISO TR9790 (ISO 1997) and Irwin (2002). The dummy was designed to host four units of 32 channel in-dummy Data Acquisition System with total 128 channel capacity. The head is constructed with PVC skin and plastic skull to simulate human head structure. The neck consists of a rubber design with metal discs, which can be tuned with rubber buffers.

Externally applied unbalanced forces and their corresponding impulses are generally excluded from consideration in regards to the evaluation of the collision phase events for a system comprised of two motor vehicles undergoing collinear impact. This exclusion is generally warranted secondary to the fact that the collision force and its corresponding impulse are dominant during the collision phase. Conceptually, two exclusions exist to this approach. The first is the situation in which significant physical restraints are present to the displacement of one or both collision partners and are of sufficient magnitude as to require inclusion. Generally, this represents the exceptional case and includes, but is not limited to, situations in which one vehicle is snagged, in a non-eccentric manner, by a rigid narrow-width object such as a pole or other similar restraint, prior to the occurrence of the subsequent vehicle-to-vehicle collision under evaluation.

Over the past years many have been predicting various dramatic changes in the vehicle including automatic route guidance, the office in the vehicle, and the auto PC. There are a number of factors which need to come together before significant momentum can develop toward realizing any of these predictions. This paper enumerates these factors and explores the current state and possible evolution of each. While each of these factors could stall progress, the linchpin is likely to be wireless communication. The current state of wireless and its capabilities going forward are examined in depth.