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This paper discusses simplified lumped parameter thermal modeling of power train components. In particular, it discusses the tradeoff between model complexity and the ability to correlate the predicted temperatures and flow rates with measured data. The benefits and problems associated with using a three lumped mass model are explained and the value of this simpler model is promoted. The process for correlation and optimization using modern software tools is explained. Examples of models for engines and transmissions are illustrated along with their predictive abilities over typical driving cycles.

This paper discusses the feasibility and issues associated with integrating a consumer off-the shelf product into a vehicle. For this evaluation, we selected a handheld personal computer (HPC), cellular telephone and modem to integrate with the vehicle audio, climate and system controls. Connectivity between the HPC and the vehicle is established by the use of the standard infrared serial data link that comes with the HPC. Connectivity outside the vehicle uses a cellular telephone for voice and a cellular digital packet data (CDPD) modem for data. This system is built into the Dodge ESX-2 hybrid powered concept vehicle for demonstration.

The rapid growth of information technology has the potential to affect many of the reasons why people drive. The Internet is arguably the most significant recent milestone in the growth of information technology. This paper examines the ways Internet communication might affect the travel experience by a) eliminating traditional reasons for personal travel, b) providing new reasons, c) changing the balance between personal and freight travel, and d) changing trip length distribution. Changes of the types listed could affect the product demand "mix" for electric, hybrid-electric and fuel cell vehicles being developed.

To understand how the passenger compartment cavity interacts with the surrounding panels (roof, windshield, dash panel, etc) a numerical panel contribution analysis was performed using FEA and BEA techniques. An experimental panel contribution analysis was conducted by Reiter Automotive Systems. Test results showed good correlation with the simulation results. After gaining some insight into panel contributions for power train noise, an attempt was made to introduce beads in panels to reduce vibration levels. A fully trimmed body structural-acoustic FEA model was used in this analysis. A network of massless beam elements was created in the model. This full structural-acoustic FEA model was then used to determine the optimal location for the beads, using the added beams as optimization variables.

A few years ago, electric vehicles (EVs) were considered to be objects of the distant future … technology that was still in its infancy, not yet ready and for those outside the “high pollution” areas probably not even worth the expenditure. But the present day scenario has changed dramatically. In the United States of America, several states are following California's lead and the need for the operating fleets to commit to purchase of Zero Emission vehicles (ZEVs) is becoming a requirement. In order to make the technology available to the utilities … as well as the public, state of the art, affordable batteries are essential for making EVs a reality and an effective means of transportation.

Due to new regulations, emissions development and compliance testing have become more complex. The amount of data acquired, the number of test types, and the variety of test conditions have increased greatly. Due to this increase, managing test information from request to analysis of results has become a critical factor. Also, automated test result presentation and test storage increases the value and quality of each test. This paper describes a computer system developed to cope with the increasing complexity of vehicle emission testing.

The J1850 bus requirements promote an unique and well characterized physical layer behavior developed through the learning curve of previous multiplex solutions. Design requirements such as: 1) Reliably interconnecting all of the vehicle's most complex modules, 2) Consistently withstanding the vehicle's harsh environment, and 3) Meeting SAE's functionality requirements, were all a formidable task to achieve. This paper will highlight the path taken to achieve a J1850 Bus interface which successfully met all of the design and functional goals. Chrysler's C2D insights will be discussed and related to goals for J1850. Other design considerations will also be discussed such as EMC issues, custom test equipment, and vehicle and component testability. In turn, silicon processes with special structures and topologies will be discussed relating the specific design with the needed electrical behavior. The HIP7020 J1850 BUS TRANSCEIVER I/O for MULTIPLEX WIRING accomplishes these requirements.

MIL 3's OPNET simulator was used to model Chrysler's J1850 bus. Modeled were both J1850 bus characteristics and those portions of control modules (e.g., the engine controller) which communicate on the bus. Current Chrysler control module algorithms and proposed Chrysler J1850 message formats were used to design the control module models. The control module models include all messages which are transmitted at fixed intervals over the J1850 bus. The effects of function-based messages (e.g., messages to be transmitted on a particular sensor or push-button reading) on system load were investigated by transmitting an additional message with a fixed, relatively high priority at 50 millisecond intervals.

The UBHC emissions during cold starting need to be controlled in order to meet the future stringent standards. This requires a better understanding of the characteristics of the time resolved UBHC signal measured by a high frequency FID and its phasing with respect to the valve events. The computer program supplied with the instrument and currently used to compute the phase shift has many uncertainties due to the unsteady nature of engine operation during starting. A new technique is developed to measure the in-situ phase shift of the UBHC signal under the transient thermodynamic and dynamic conditions of the engine. The UBHC concentration is measured at two locations in the exhaust manifold of one cylinder in a multicylinder port injected gasoline engine. The two locations are 77 mm apart. The downstream probe is positioned opposite to a solenoid-operated injector which delivers a gaseous jet of hydrocarbon-free nitrogen upon command.

Engine misfires cause a negative impact on exhaust emissions. Severe cases could damage the catalyst system permanently. These are the basic reasons why CARB (California Air Resources Board) mandated the detection of engine misfires in their OBD II (On-Board Diagnostics II) regulations. For the last several years, automobile manufacturers and their suppliers have been working diligently on various solutions for the “Misfire Detection” challenge. Many have implemented a solution called “Crankshaft Velocity Fluctuation” (CVF), which utilizes the crank sensor input to calculate the variation of the crankshaft rotational speed. The theory is that any misfires will contribute to a deceleration of the crankshaft velocity due to the absence of pressure torque. This approach is marginal at best due to the fact that there could be many contributors to a crankshaft velocity deceleration under various operating conditions. To sort out which is a true misfire is a very difficult task.

Voltage and current surges are a major concern when it comes to ensuring the functional integrity of electrical and electronic components and modules in an automobile system. This paper presents a computer simulation study for analyzing the effect of high voltage spikes and current load dump on a new Integrated Driver/Receiver (IDR) IC, currently being developed for a J1850 Data Communication Bus in an automobile. It describes the modeling and simulation of the protection structure proposed for the device. The simulation study yields a prediction of current and voltage capability of the protection circuit based on thermal breakdown and transient responses of the circuit. Two levels of modeling, namely, the behavioral level model and the component level model, are used to generate the simulation results. Experimental data will be acquired and used to validate the simulation model when the actual device becomes available.

As a cost effective solution to making microcontroller based systems “J1850[1] aware”, a peripheral device (the HIP7010) was developed to extend the capabilities of standard microcontrollers. From the perspective of the Host, the peripheral device handles J1850 messages as a series of bytes (similar in concept to a universal asynchronous receiver/transmitter [UART]). The architecture of the HIP7010 is discussed. The design of the J1850 interface, state machine, status/control blocks, cyclical redundancy check (CRC) hardware, host interface, and fail-safe features are detailed. Illustrations are provided of: Host/HIP7010 interfacing; message transmission and reception; error handling; and In-Frame Response (IFR) generation.

The changes in reliability of the Electrical/Electronic Systems of a vehicle-line during its early design and development engineering processes have been studied. A computerized vehicle failure tracking system was used to provide results from several stages of early development vehicle testing at the proving grounds. The data were analyzed using a software program that assumes that failures in a repairable system, such as a car, occur as a nonhomogeneous Poisson process. Results suggest that, under normal circumstances, a significant and quantitative improvement in reliability is achievable as the system or component design progresses through the early design and development processes. This also provides a means of predicting future system(s) reliability when the system(s) is in production.

Federal legislation mandates that automotive OEMS provide occupant protection in collisions involving front and side impacts This legislation, which is to be phased-in over several years, covers not only passenger cars but also light-duty trucks and multipurpose passenger vehicles (MPVs) having a gross vehicle weigh rating (GVWR) of 8,500 lb (3,850 kg) or less. During a frontal impact, occupants within the vehicle undergo rapid changes in velocity. This is primarily due to rapid vehicle deceleration caused by the rigid nature of the vehicle's metal frame components and body assembly. Many of today's vehicles incorporate deformable, energy-absorbing (EA) structures within the vehicle structure to manage the collision energy and slow the deceleration which in turn can lower the occupant velocity relative to the vehicle. Occupant velocities can be higher in light-duty trucks and MPVs having a full-frame structure resulting in increased demands on the supplemental restraint system (SRS).

Chrysler Corporation Interior Electrical\Entertainment Department currently has three different mounting tab configurations on the radio escutcheon required by five platforms for radio installation. Prior to the re-organization into platforms, the corporation had one corporate mounting configuration. The reorganization into platforms encouraged diversification including different radio mounting locations. This however, requires three separate part numbers for the same radio unit, resulting in additional cost. How can we assure product diversification between platforms while controlling cost and managing complexity?

To evaluate and refine interior architecture of the new Dodge Ram pickup truck three years before production, a road worthy interior package validation buck was built using a fiberglass body shell. Molds for the shell were made using CAD/CAM techniques. Advanced CAD/CAM techniques were used to build the interior buck of a subsequent model from individual panels molded in carbon fiber. This buck also included inner structural panels and interior trim components taken from CAD data. For this and subsequent new vehicle programs, refinement of construction techniques allows the bucks to serve as aids in product design and manufacturing feasibility studies.

Chrysler Corporation has developed an 8.0-liter engine for light truck applications. Numerous features combine to produce the highest power and torque ratings of any gasoline-fueled light truck engine currently available while also providing commensurate durability. These features include: a deep-skirt ten-cylinder 90° “V” block, a Helmholtz resonator intake manifold that enhances both low and mid-range torque, light die cast all-aluminum pistons for low vibration, a unique firing order for smooth operation, a “Y” block configuration for strength and durability, a heavy duty truck-type thermostat to control warm up, and a direct ignition system.

Chrysler Corporation's Jeep and Truck platform implemented a new design and prototype process for the body-in -white of a new pickup truck. A team approach achieved concurrent body design, stamping die design, assembly process development, and assembly tooling development. The first domestic US industry use of a 100% electronic design and release system was instrumental in the process. The new process produced a prototype body-in-white on time at 95 WBVP (weeks before volume production) with the highest level of production-intent components ever achieved within Chrysler at this stage of development.

This paper presents the development of a test procedure for evaluation of inadvertent deployment of air bags. The methodology and early development of the procedure is discussed along with additional criteria thought to be required for trucks and sport utility vehicles. Tests conducted address severe off-road use in relation to air bag sensing systems. Data is collected from accelerometers. After worst case test conditions are identified (examples include rough road, snow plowing and jerk towing events), the data is analyzed and comparisons for design decisions can be made.

A Methanol Concentration Smart Sensor has been developed to support the demand for alternately fueled vehicles operating on blends of methanol and gasoline in any mixture up to 85% methanol. The sensor measures concentration by exploiting the difference in dielectric properties between methanol and gasoline. The measurement is made based on the distributed capacitance of a coil of wire, contained in a reservoir through which the fuel passes. This signal, along with temperature compensation inputs, is then fed to an integral microprocessor, which provides a voltage output proportional to the methanol concentration of the fuel. The Powertrain Controller uses this information to modify injector pulse width and provide proper spark advance. This paper will explain the sensor's development methodology and function.