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Side impact accounts for a significant source of societal harm, injury and death. To address this issue, Europe and US have introduced legislation to be met for the new vehicle certification. In an effort to meet these regulations and the market demand for safety, Automotive manufacturers have significantly improved vehicle side structure integrity and introduced side impact airbags are for added protection. Today, passenger vans, light truck and sport-utility type vehicles are all popular consumer choices in the US. These vehicles differ significantly from passenger cars in many respects and as such need special design considerations for side airbags. Here, MADYMO-3D model of a generic passenger van / Sport-Utility type vehicle is created and correlated to FMVSS-214 side impact crash test. This model is used to evaluate both door and seat mounted side airbag designs in different orientations at standard test impact condition and at a higher speed.

Short timing and complexes strategies are mandatory in a competitive market as automotive industry. Therefore quality problems identification during and after the coding phase, may be the difference between the business success and undesired conflicts with customer, solving problems that were not previously identified. Consequently the usage of technique Mahalanobis Taguchi System (MTS) to analyze coding metrics, create an environment to improve the final product quality and mitigate potential problems later identified.

Continuous Improvement activities are often based on a list of top concerns, such as highest RPN (Risk Priority Number) on the PFMEA (Process Failure Modes and Effects Analysis), warranty items, or scrap rates. But a company is in business to make a profit for its stockholders. Therefore, money should be considered, rather than just technical engineering tools and RPNs. Current PFMEA methodology (See references 1 and 2) focuses on delivering quality parts to the customer. The financial impact of various potential process problems is not considered directly. A new and extended technique called FMERA (pronounced Fuh-MAIR-uh) can identify and prioritize the process part of potential problems that have the most financial impact on an operation. Alternatives can be evaluated to maximize the financial benefits. FMERA is a method for getting the voice of the stockholder into process decisions.

Hazard analysis plays an important role in the development of safety-critical systems. Hazard analysis techniques have been used in the development of conventional automotive systems. However, as future automotive systems become more sophisticated in functionality, design, and applied technology, the need for a more comprehensive hazard analysis approach has arisen. In this paper, we describe a comprehensive hazard analysis approach for system safety programs. This comprehensive approach involves applying a number of hazard analysis techniques and then integrating their results. This comprehensive approach attempts to overcome the narrower scope of individual techniques while obtaining the benefits of all of them.

The increasing features and complexity of today's automotive architectures are becoming increasingly difficult to manage. Each new innovation typically requires additional mechanical actuators and associated electrical controllers. The sheer number of black boxes and wiring are being limited not by features or cost but by the inability to physically assemble them into a vehicle. A new architecture is required which will support the ability to add new features but also enable the Vehicle Assembly Plants to easily assemble and test each subsystem. One such architecture is a distributed multiplex arrangement that reduces the number of wires while enabling flexibility and expandability. Previous versions have had to deal with issues such as noise immunity at high switching currents. The LIN Bus with its low cost and rail-to-rail capability may be the key enabling technology to make the multiplexed architecture a reality.

Seat belts are the primary occupant-protection devices for vehicle crashes. Field statistics show that proper usage of seat belts substantially contributes to decreases in the fatality rate and injury level. To collect first-hand information regarding seat belt comfort and usability, a questionnaire survey was conducted. The most significant problems were found as belt trapping in the door, awkward negotiating with clothes, belt twisting, belt locking up, and difficulty to locate the buckle. The survey results indicated that drivers who are over 40 years old have more complaints than younger drivers. When the driver's age increases to 55 and above, belt pulling force and inappropriate and loose fitting of the belt on the body become major issues. Female drivers have more complaints than male drivers. Short statured drivers need both hands to pull and guide the retracting of the belt.

In this study, US and UK accident data were analyzed to identify parameters that may influence rollover propensity to analyze driver injury rate. The US data was obtained from the weighted National Automotive Sampling System (NASS-CDS), calendar years 1992 to 1996. The UK pre-roll data was obtained from the national STATS 19 database for 1996, while the injury information was collected from the Co-operative Crash Injury Study (CCIS) database. In the US and UK databases, rollovers accounted for about 10% of all crashes with known crash directions. In the US and UK databases, most rollovers occurred when the vehicle was either going straight ahead or turning. The propensity for a rollover was more than 3 times higher when going around a bend than a non-rollover. In the UK, 74% of rollovers occurred on clear days with no high winds and 14% on rainy days with no high winds. In the US, 83% of rollovers took place in non-adverse weather conditions and 10% with rain.

In this study, U.S. accident data was analyzed to determine interior contacts and injuries for front-seated occupants in rollovers. The injury distribution for belted and unbelted, non-ejected drivers and right front passengers (RFP) was assessed for single-event accidents where the leading side of the vehicle rollover was either on the driver or passenger door. Drivers in a roll-left and RFP in roll-right rollovers were defined as near-side occupants, while drivers in roll-right and RFP in roll-left rollovers were defined as far-side occupants. Serious injuries (AIS 3+) were most common to the head and thorax for both the near and far-side occupants. However, serious spinal injuries were more frequent for the far-side occupants, where the source was most often coded as roof, windshield and interior.

Recent advances in dependable embedded system technology, as well as continuing demand for improved handling and passive and active safety improvements, have led vehicle manufacturers and suppliers to actively pursue development programs in computer-controlled, by-wire subsystems. These subsystems include steer-by-wire and brake-by-wire, and are composed of mechanically de-coupled sets of actuators and controllers connected through multiplexed, in-vehicle computer networks; there is no mechanical link to the driver. This paper addresses fundamental benefits and issues of steer-by-wire, especially those related to automated vehicle control and steering feel quality as perceived by the driver.

The lateral runout of disc brake corner components can lead to the generation of brake system pulsation. Emphasis on reducing component flatness and lateral runout tolerances are a typical response to address this phenomenon. This paper presents the results of an analytical study that examined the effect that the attachment of the wheel to the brake corner assembly could have on the lateral distortion of the rotor. An analysis procedure was developed to utilize the finite element method and simulate the mechanics of the assembly process. Calculated rotor distortions were compared to laboratory measurements. A statistical approach was utilized, in conjunction with the finite element method, to study a number of wheel and brake corner parameters and identify the characteristics of a robust design.

This paper describes the development and implementation of an Engine Drag Control algorithm to improve vehicle stability performance. Engine drag can occur on low and high coefficient surfaces when the driver suddenly releases the throttle. If the engine drag force becomes larger than the frictional force between the tire and the road, the tires will break loose from the surface and slip. This could induce vehicle instability especially with rear drive vehicles on low-coefficient surfaces. The EDC algorithm has been developed to provide accurate control of the wheels. EDC will help reduce the yaw rate of the vehicle and thus achieve greater vehicle stability. The paper also presents methods used to test the robustness of such a system. The purpose of the testing was to ensure that there would be no false activations of EDC under normal driving conditions and also to ensure that, when the system is active, it is mostly transparent to the driver.

This paper is an extension to the work presented in part I [1]. The control objective is still the same - use a logic based control design technique to assign a wheel slip, λ, to each corner of a vehicle, to track overall desired vehicle dynamics. As in part I, a fuzzy logic based controller is the primary control, with additional logic to select the inside/outside classifiers for the wheels. In part I, only the reduction of yaw rate error, e, was considered. It was shown that, although the overall system had satisfactory performance, there was slight deteriorization in the tracking performance when trying to compensate through a significant vehicle sideslip angle, β. In this paper, additional logic is introduced into the control to limit the vehicle sideslip angle, β; thus, allowing for a more robust desired yaw rate, Ωd, tracking control performance. The emergency lane change maneuver is simulated to show the effectiveness of the redesigned control.

This work examines the development and implementation of a pulsing brake control system as part of a Forward Collision Warning (FCW) System for an Adaptive Cruise Control (ACC) prototype vehicle. The brake pulse is a likely candidate to be employed with visual and auditory cues in the event of an imminent collision alert level when the driver is not in ACC mode.

Utilization of direct injection systems is one of the most promising technologies for fuel economy improvement for SI engine powered passenger cars. Engine performance is essentially influenced by the characteristics of the injection equipment. This paper will present CFD analyses of a swirl type GDI injector carried out with the Multiphase Module of AVL's FIRE/SWIFT CFD code. The simulations considered three phases (liquid fuel, fuel vapor, air) and mesh movement. Thus the transient behavior of the injector can be observed. The flow phenomena known from measurement and shown by previous simulation work [2, 7, 10, 11] were reproduced. In particular the simulations shown in this paper could explain the cause for the outstanding atomization characteristics of the swirl type injector, which are caused by cavitation in the nozzle hole.

The structure of the racecar has been the subject of much discussion with regard to crash safety. The stiffness of the structure, the amount of crush and the resulting deceleration were being judged, in some instances, as too stiff or not stiff enough for the driver. Much of this discussion centered on crash incidents for which no deceleration data were available from crash recorders (black boxes). In this paper, crash test dummy (Anthropomorphic Test Device ATD) results are compared for various idealized deceleration-time histories (deceleration pulses) that represent various structural crush characteristics. A crash velocity of 64.4 KPH (40 MPH) against a wall was used to represent a life threatening energy level.

The purpose of this paper is to evaluate through simulations the effects of active chassis systems on vehicle propensity to rollover caused by aggressive handling maneuvers. A 16 degree-of-freedom computer model of a full vehicle is used for this purpose. It includes models of active chassis systems and the associated control algorithms, and allows for simulation of vehicle dynamic behavior under large roll angles. The controllable chassis systems considered in this investigation are active rear steer, brake based vehicle stability enhancement system and active anti-roll bar. The maneuvers used in simulation are the double lane change and the fishhook maneuvers with increasing steering amplitudes. The vehicle represents a midsize SUV with a marginal static stability factor of 1.09 and aggressive tires. The results of simulations demonstrate that the uncontrolled vehicle rolls over in both maneuvers when the steering angle is sufficiently large.

The focus of this study is to validate the predictive capability of a recently developed physiology based thermal comfort modeling tool in a realistic thermal environment of a vehicle passenger compartment. Human subject test data for thermal sensation and comfort was obtained in a climatic wind tunnel for a cross-over vehicle in a relatively warm thermal environment including solar load. A CFD/thermal model that simulates the vehicle operating conditions in the tunnel, is used to provide the necessary inputs required by the stand-alone thermal comfort tool. Comparison of the local and the overall thermal sensation and comfort levels between the human subject test and the tool's predictions shows a reasonably good agreement. The next step is to use this modeling technique in designing and developing energy-efficient HVAC systems without compromising thermal comfort of the vehicle occupants.

In this paper, finite element shape optimization is used to determine the optimum air cleaner shape and rib design for low shell noise. Shape variables are used to vary the height and location of rib elements, as well as vary the shape of the air cleaner surfaces. The optimization code evaluates each design variation and selects a search direction that will reduce surface velocity. Sound power radiation is calculated for each optimized design using an acoustic code. Large reductions in shell noise were achieved by optimizing the shape of the air cleaner surface and rib design. Optimization of the rib pattern alone yielded a local optimization, as opposed to a global optimization that represented the best possible design.

Electric power steering (EPS) is an advanced steering system that uses an electric motor to provide steering assist. Being a new technology it lacks the extensive operational history of conventional steering systems. Also conventional systems cannot be used to command an output independent of the driver input. In contrast EPS, by means of an electric motor, could be used to do so. As a result EPS systems may have additional failure modes, which need to be studied. In this paper we will consider the requirements for successful EPS operation. The steps required to develop diagnostics based on the requirements are also discussed. The results of this paper have been implemented in various EPS-based programs.

A finite element model of a folded airbag with the module cover and steering wheel system was developed to estimate the injury numbers of a 5th percentile female dummy in an out-of-position (OOP) situation. The airbag model was correlated with static airbag deployments and standard force plate tests. The 5th percentile finite element dummy model developed by First Technology Safety Systems (FTSS) was used in the simulation. The following two OOP tests were simulated with the airbag model including a validated steering wheel finite element model: 1. Chest on air bag module for maximum chest interaction from pressure loading (MS6-D) and 2. Neck on air bag module for maximum neck interaction from membrane loading (MS8-D). These two simulations were then compared to the test results. Satisfactory correlation was found in both the cases.