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A comparison of the 50th percentile male THOR-LX and Hybrid III 50th percentile male dummy lower leg was conducted via component and full scale barrier testing. In the component tests, isolated THOR-LX and Hybrid III lower legs were impacted in two different test set-ups where the tibia was impacted at three different impact points. The foot without a shoe was impacted in two different test set-ups at six different impact points. A shoe impact study was also conducted to determine the effect of a shoe on the results and to determine how many impacts a shoe can withstand at each point before properties of the shoe begin to change. For these tests, the THOR-LX and Hybrid III lower legs were repeatedly impacted at four different points on the foot with a shoe. For the full scale barrier testing, the THOR-LX or Hybrid III lower legs were attached to a belted Hybrid III 50th percentile male dummy. The dummy was positioned in a compact car for each test.

With the increasing demand for safety, energy saving and emission reduction, Advanced High Strength Steels (AHSS) have become very attractive materials for automobile makers. The usage of AHSS materials is projected to grow significantly in the next 5-10 years with new safety and fuel economy regulations. These new materials have significant manufacturing challenges, particularly for welding and stamping. Welding of AHSS remains one of the technical challenges in the successful application of AHSS in automobile structures, especially when durability of the welded structures is required. In this study, 2.0 mm uncoated DP600 and 2.0 mm uncoated boron (heat treated) steel lap joint configuration was investigated. Metallurgical properties of the DP600 to boron steel dissimilar steel lap joints were evaluated using optical microscopy. Static and fatigue tests were conducted on these joints.

Bolted joint separation occurs when components of a joint are no longer capable of maintaining a clamp load. The clamp load of a joint is the resultant of various factors such as the strength of joining components, geometry, and the surface condition of the joined parts. The fastener installation torque is a very critical parameter that contributes towards achieving the desired clamping force at the joint during the assembly process. Thread rolling screws are increasingly being used in many automotive structural applications. The thread rolling screws are easy to install, are self aligning, and offer a torque prevailing feature with improved vibration resistance when mated with a un-threaded nut. This combination results in a robust joint and low field costs. They also offer increased joint strength by work hardening the mating nut interface.

A four valve controller and electronic control circuits were developed to control the displacement of hydrostatic pump/motors (P/M's) utilized in an automobile with a hydrostatic transmission and hydropneumatic accumulator energy storage. Performance of the control system was evaluated. The controller uses four high-speed, two-way, single-stage poppet valves, functioning in the same manner as a 4-way, 3-position spool valve. Two such systems were used to control the displacement of two P/Ms, each system driving a front wheel of the vehicle. The valves were controlled electronically by a distributed-control dead-band circuit and valve driver boards. Testing showed that the control system's time response satisified driving demand needs, but that the control system's error was slightly larger than desired. This may lead to complications in some of the vehicle's operating modes.

This study compared laser and fine plasma technology for cutting typical electro-galvanized steel and aluminum automotive stampings. Comparisons were made of various aspects of cut quality, accuracy, disturbance of parent material, cycle time, and capital and operating costs. A sensitivity analysis was included to determine how different scenarios would impact the operating costs. It was found that both processes were capable of high quality cuts at 3800mm/min. Capital savings were achievable through the fine plasma system, but careful consideration of the specific application was essential. This work will allow for an advised comparison of options for sheet metal flexible cutting.

As-cast or as-solution treated cast aluminum A319 has copper solutions within its aluminum dendrite. These copper solutions precipitate out to form Al2Cu through a sequence of phase changes and bring with them volume changes at elevated temperatures. These volume changes, referred to as thermal growth are irreversible. The magnitude of thermal growth at a material point is decided by the temperature history of the material point. When an under aged or non heat treated cast aluminum is exposed to non-uniform temperature such as that during engine operation, thermal growth leads to non-uniform volume change and thus additional self balanced stresses. These stresses remain inside material as residual stresses even when the temperature of the material is uniform again. In the present paper, numerical analysis method for thermal growth is developed and integrated into engine operation analysis.

Due to complexities of interaction among gears and crescent-shaped island, a crescent oil pump is one of the most difficult auto components to model using three dimensional Computational Fluid Dynamics(CFD) method. This paper will present a novel approach to address the challenges inherent in crescent oil pump modeling. The new approach is incorporated into the commercial pump design tool PumpLinx from Simerics, Inc.. The new method is applied to simulate a production crescent oil pump with inlet/outlet ports, inner/outer gears, irregular shaped crescent island and tip leakages. The pump performance curve, cavitation effects and pressure ripples are studied using this tool and will be presented in this paper. The results from the simulations are compared to the experiment data with excellent agreement. The present study shows that the proposed computational model is very accurate and robust and can be used as a reliable crescent pump design tool.

Typical automotive joints are lap, coach, butt and miter joints. In tubular joining applications, a coach joint is common when one tube is joined to another tube without the use of brackets. Various fusion joining processes are popular in joining coach joints. Common fusion joining processes are Gas Metal Arc Welding (GMAW), Laser and Laser Hybrid, and Gas Tungsten arc welding (GTAW). In this study, fusion welded 2.0 mm uncoated DP780 steel coach joints were investigated. Laser, Gas metal arc welding (GMAW), and laser hybrid (Laser + GMAW) welding processes were selected. Metallurgical properties of the DP780 fusion welds were evaluated using optical microscopy. Static and fatigue tests were conducted on these joints for all three joining processes. It was found that joint fit-up, type of welding process, and process parameters, especially travel speed, have significant impact on static and fatigue performance of the coach joints in this study.

The traditional moveable glass window seal development process has relied heavily on physical prototypes for design verification. Due to frequent styling changes and an overall reduction in design time, physical prototypes for the glass window seals have proven to be inadequate. Utilization of computer aided engineering (CAE) tools is necessary in order to shorten lead time. CAE tools will help to decrease expensive prototyping, free up valuable manufacturing line time, and improve overall quality. A cross functional approach has been applied to expand the scope beyond traditional methods of moveable glass window seal design, such as wedged boarding, into new computerized modeling methods. The CAE was used to address major requirements of the glass window seals including glass velocity, glass stall force, sealing-ability, seal durability, seal assembly, seal appearance, and regulator motor current.

The stabilizer bar attachments problem can not be simply analyzed by using linear FEA methodology. The large deformation in the bushing, the elastic-plastic material property in the bushing retainer bracket, and the contact between different parts all add complexity to the problem and result in the need for an analysis method using a non-linear code, such as ABAQUS. The material properties of the bushing were experimentally determined and applied to the CAE model. It was found that using strains to estimate the fatigue life was more accurate and reliable than using stress. Many modeling techniques used in this analysis were able to improve analysis efficiency.

While SAE double inverted flares have been in use for decades, leaking joints continue to be a problem for OEMs in production settings consuming time and energy to detect and correct them before releasing vehicles from the assembly plant. It should be noted that this issue is limited to first-time vehicle assembly; once a flared brake tube joint is sealed at the assembly plant it remains sealed during normal customer usage. From their inception through the late 1980s most brake tubes have been 3/16″ nominal diameter. With the advent of higher flow requirements of Traction Control and Yaw/Stability control systems, larger tubes of 1/4″ and 5/16″ size have also been introduced. While it was known that the first-time sealing capability of the 3/16″ joint was not 100%, leakers were generally containable in the production environment and the joint was regarded as robust.

For the application of advanced clean combustion technologies, such as diesel HCCI/LTC, a compressor with high efficiency over a broad operation range is required to supply a high amount of EGR with minimum pumping loss. A compressor with high pitch of vaneless diffuser would substantially improve the flow range of the compressor, but it is at the cost of compressor efficiency, especially at low mass flow area where most of the city driving cycles resides. In present study, an ultra low solidity compressor vane diffuser was numerically investigated. It is well known that the flow leaving the impeller is highly distorted, unsteady and turbulent, especially at relative low mass flow rate and near the shroud side of the compressor. A conventional vaned diffuser with high stagger angle could help to improve the performance of the compressor at low end. However, adding diffuser vane to a compressor typically restricts the flow range at high end.

Grunt is a structure-born noise caused by resonance of the steering gear torsion bar (T-bar) in an HPAS (Hydraulic Power Assist Steering) system. The goal of this work was to develop techniques to quantify and predict grunt in a RV (rotary valve) steering gear system. First, vehicle testing was used to identify an objective metric for grunt: y = dynamic pressure in the return line. Then, a computer simulation was developed to predict y as a function of two known control factors. The simulation results were correlated to measurements on a test vehicle. Finally, the simulation was expanded to include two additional control factors, and grunt predictions were demonstrated on a different test vehicle.

Air-conditioning (A/C) induced moan is a very commonly observed phenomenon in automotive refrigerant systems. Since most of the automotive A/C systems cycle ON/OFF four to six times every minute, the A/C induced moan is quite readily audible under engine idle and even while driving, especially under lower engine/vehicle speeds. It is not unusual for an A/C compressor to moan or not, on some vehicle/s under certain operating conditions. Most of the OEMs resolve or suppress the A/C moan potential to barely audible levels. However, under some unique and extreme operating conditions, A/C moan is quite readily induced and often results in customer complaints. This paper discusses A/C moan related root-causes, sources and paths of propagation. A systematic diagnostic test-procedure is also described to diagnose and develop the needed most cost-effective design-fixes. Finally, based on this case-study - some objective targets are recommended to suppress the A/C moan to acceptable levels.

The traditional analysis of squeal noise for drum brakes is done in a separate approach, with CAE and laboratory/experimental techniques done independently or in a non-iterative sequential manner. In this paper, an innovative approach of directing the frequency response testing based on CAE is used and the overall process is embedded in a system approach. The drum brake design was changed to accomplish higher loads in a car. The initial results of the tests came out noise during the vehicle test. After retrieving the noisy parts from the vehicle, it was tested for frequency response, but in a directional manner suggested by the CAE model. This new approach hasn't been done before in industry practice. The CAE identified that two modes (around the noise frequency) swapped their orders compared to the old design and suggested design changes. The new design was evaluated with a mocked up prototype. This was followed by getting cast parts and testing them for frequency response.

Network communications are widely being deployed in vehicle electrical architecture due to its low cost for embedded electronic and advance it provides. Nowadays, different types of protocols may be used to allow the communication among the modules (e.g.: CAN, LIN, FLEX RAIL, etc). Modules may receive or send data throughout a physical layer. And they are powered up by using different types of cables, grounds and shields which create a high complexity in terms of wiring harnesses installation, weight and cost. Data and power transmission throughout a unique line is a real and promising available technology.

Due to the challenges in quantifying hand loads in manufacturing environments it is often assumed that the load is evenly distributed between the hands, even when handling parts with non-uniform mass distribution. This study estimated hand loads for six female subjects, when handling a custom part in 8 different configurations (2 weights, 4 CofM locations). The calculated hand loads varied from 20 to 50% of the weight being handled. The magnitude of asymmetrical hand loading depended on both the part orientation and the location of the CoM. Based on this study the knowledge of part weight, CofM location and hand positioning will allow the users of digital human models to perform more realistic and reliable task analysis assessments as the force distributions will be more representative of the actual loading rather than simply assuming the load is evenly distributed between the hands.

A finite element methodology, based on implicit numerical integration procedure, for simulating oil-canning tests on Door assemblies is presented. The method takes into account nonlinearities due to geometry, material and contact between parts during deformation. The simulation results are compared with experimental observations. Excellent correlation between experimental observations and analytical predictions are obtained in these tests. Armed with the confidence in the methodology, simulations on a door assembly are conducted to study the gage and grade sensitivities of the outer panel. The sensitivity studies are conducted on three different grades of steel for the outer panel. Further studies are conducted to understand the effects of manufacturing (forming operation) on the oil canning behavior of door assembly. Results demonstrate the utility of the method in material selection during pre-program design of automotive structures.

The US Automotive Materials Partnership (USAMP) and the US Department of Energy launched the Magnesium Powertrain Cast Components Project in 2001 to determine the feasibility and desirability of producing a magnesium-intensive engine; a V6 engine with a magnesium block, bedplate, oil pan, and front cover. In 2003 the Project reached mid-point and accomplished a successful Decision Gate Review for entry into the second half (Phase II) of the Project. Three tasks, comprising Phase I were completed: (1) evaluation of the most promising low-cost, creep-resistant magnesium alloys, (2) design of the engine components using the properties of the optimized alloys and creation of cost model to assess the cost/benefit of the magnesium-intensive engine, and (3) identification and prioritization of scientific research areas deemed by the project team to be critical for the use of magnesium in powertrain applications.

This paper describes a transient, thermodynamic, crank angle-based engine model in Modelica that can be used to simulate a range of advanced engine technologies. A single cylinder model is initially presented and described, along with its validation against steady-state dynamometer test data. Issues related to this single cylinder validation are discussed, including the appropriate conservation of hot residual gases under very early intake valve opening (IVO) conditions. From there, the extension from a single cylinder to a multi-cylinder V8 engine model is explained and simulation results are presented for a transient cylinder-deactivation scenario on a V8 engine.