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A new electronically controlled transaxle has been put into production for Chrysler's family of LH cars. Among the attributes of this new transaxle are its ability to handle engines of high torque and high power coupled with high-speed shifts. Engine torque management is used in specific operating regimes. A feature of the transaxle is electronic modulation of the converter clutch. A number of logic features have been combined with hardware to provide good performance and shift quality over a wide operating range. An output transfer chain and a hypoid gear set are used to provide torque to the front wheels in a longitudinal power train orientation. Obtaining acceptable endurance life of the hypoid gears within an aluminum housing presented a significant challenge. New approaches were required to provide a chain-sprocket system with acceptable noise characteristics.

Simplified mathematical modeling has been employed to investigate the relationship between automobile forestructure energy absorption and the restraint loads applied to passengers during a 30 mph barrier collision. A two-massmodel was developed and validated to compute restraint loading from a given passenger compartment deceleration. The effect of various deceleration curves, representing forestructure modifications, is reported. A “constant force” restraint system is also evaluated.

A unique opportunity arose to make a direct comparison of aluminum, sheet molding compound (SMC) and steel using a common hood design. In considering all possible material combinations of inner and outer panels, it was discovered that some of the combinations were incompatible due to material properties. Only the compatible material combinations were considered. Three different joining techniques - welding, bonding and bonded hem flanging - were evaluated. The cost, weight and structural performance of the chosen hood material combinations were established. Areas of further development were identified, including design optimization for specific material combinations.

The paper presents a new method, based on standard laboratory cup tests, for predicting the formability of materials; in the example provided, the forming potentials of four new materials are shown. The properties of stretchability and drawability, which are the principal factors defining a material's forming limits, may be assessed using the Olsen spherical cup test and the Swift flat-bottomed cup test. In the shape analysis procedure described, the minimum amount of deformation needed to fix a desired shape is determined. Then necessary adjustments to tooling for optimum sheet metal usage are made based on calculations from a new type of chart showing stretch forming ratio and draw forming ratio, providing a comparison of the formabilities of a number of materials.

A procedure has been developed for measuring the relative visibility of automotive instrument panel graphics and components. Through use of a Luckiesh-Moss Visibility Meter, discreet values of visibility can be assigned to visual targets and related to driver reaction time. Also, eyes off the road lapsed time boundaries may be established which will define visibility requirements necessary to serve the total driver population. These requirements can be translated into meaningful guidelines or standards for visibility attributes such as size, shape, color, contrast, and position of graphics, controls, and indicators. How visibility measurements are made and interpreted and the visibility measuring facility are discussed in this paper.

Starting in 1965 and continuing through 1972, the Radio Committee of the Motor Vehicles Manufacturers Association (MVMA) has been the coordinator of a number of electromagnetic research projects. These investigations have included extensive applications of the updated SAE Standard, Measurement of Electromagnetic Radiation From Motor Vehicles (20-1000 MHz)-SAE J551a. Furthermore, there were joint testing programs with the Electronic Industries Association which encompassed measuring degradation in the performance of Land Mobile Radio Service receivers resulting from varying levels of impulsive-type radiation from motor vehicles. In addition, efforts were expended in using statistical approaches for testing a number of hypotheses covering a conversion of impulsive vehicle noise data to the interference potential to Land Mobile receivers.

Resistance to dents and dings, caused by plant handling and in-service use, is generally recognized as an important performance requirement for automotive outer body panels. This paper examines the dent resistance improvements that can be achieved by maximizing surface stretch, through adjustments to the press settings, and substitution of a higher strength steel grade. Initially, the stamping process was optimized using the steel supplied for production: a Ti/Nb-stabilized, ultra low carbon (ULC) grade. The stamping process was subsequently optimized with a Nb-stabilized, rephosphorized ULC steel, at various thicknesses. The formed panels were evaluated for percent surface stretch, percent thinning, in-panel yield strength after forming, and dent performance. The results showed that dent resistance can be significantly improved, even at a reduced steel thickness, thus demonstrating a potential for weight savings.

The interaction ILLEGIBLEf the chest of the Hybrid III dummy with the air bag restrILLEGIBLEt system during a crash is complex. Forces applied to one ILLEGIBLEmponent of the dummy can generate an unexpected response in a distal part. Motion, both linear and angular, of the pelvis during impact can create an enigmatic spike in the acceleration of the chest. Because significant changes in the chest acceleration response can affect the development of an airbag system, this pelvis-chest interaction is cause for concern. The factors that appear to affect the chest acceleration spike as a result of the pelvis-chest interaction are: the mass moment of inertia of the pelvis, the interaction of the pelvis with the femur, the characteristic of the lumbar spine, and the differential velocity of the pelvis with respect to the chest.

INDUCTION heating is a process or method by which metal parts are heated by simply placing them in an alternating magnetic field. The action is that of the transformer, whereby electrical energy is transferred or passed over to another isolated electric or secondary circuit by means of the magnetic field; thus, no physical attachments or electrical contacts are necessary to have electrical currents, which are dissipated as heat, flow in the parts to be processed. The strength and frequency of the alternating magnetic field can be selected to produce any desired rate of heating and ultimate temperature. A circuit can be set up to dry lacquer at 160 deg. fahr. on thin sheet-metal parts or to melt in record time immense steel ingots. Induction heating is now commercially applied in automotive production to many processes, and these are specified.

Strain analysis of stampings is explained. The system is based on the strain distributions obtained from 0.2 in. inter-locking circle grid patterns etched on blanks. The strain distributions are related to a developed formability limit curve and the mechanical properties of the gridded blank. The evaluation of the graphic relation of the strains to the formability limit enables the press shop to determine what factors should be changed to produce stampings with less scrap and lower cost.

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.

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 describes the application of the Design for Manufacture and Assembly (DFMA) method at Chrysler. Attention is focused on the development of the clutch and brake pedal and bracketry system of the PL project in the Small Car Platform. The Chrysler DFMA procedure including competitive evaluation and value engineering was utilized during the initial design phase involving product concept development from the original functional and manufacturing requirements. After the first laboratory tests, a number of key design and manufacturing concerns surfaced and led to a second cycle of DFMA analysis. The procedure permits major design functions and manufacturing and assembly process issues and criteria to be incorporated in the initial design stages.

Five heats of vanadium-microalloyed steel with carbon contents from 0.29% to 0.40% and sulfur contents from 0.031% to 0.110% were forged into automotive spindles and air cooled. Three of the steels were continuously cast whereas the other two were ingot cast. The forged spindles were subjected to microstructural analysis, mechanical property testing, full component testing and machinability testing. The microstructures of the five steels consisted of pearlite and ferrite which nucleated on prior austenite grain boundaries and predominantly on intragranularly dispersed sulfide inclusions of the resulfurized grades. Ultimate tensile strengths and room temperature Charpy V-notch impact toughness values were relatively insensitive to processing and compositional variations. The room temperature tensile and room-temperature impact properties ranged from 820 MPa to 1000 MPa (120 to 145 ksi) and from 13 Joules to 19 Joules (10 to 14 ft-lbs), respectively, for the various steels.

Some of Chrysler's 1988 model year vehicles contain a serial bus. This paper discusses its implementation and general usage. It describes a type of bus that was designed for smart modules to be able to cost effectively transfer data within an automotive environment. This paper is a sixty plus page users manual describing how to use both the Chrysler's C2D* bus and the C2D chip. This manual contains descriptions of the vehicle system, the information usage, the message formats, the hardware interfacing requirements, the bus speed, and the C2D chip functions. The SAE Multiplex Subcommittee is currently attempting to standardize this type of bus via SAE J1850. However, until this happens, Chrysler will continue to develop, improve, and use this bus, since it exists now! Even though this bus was designed for automotive usage, it has many other possible industry applications, especially within noisy environments. Thus, after understanding the bus, other industries may become interested.

Energy management materials are widely used in automotive interiors in instrument panel, knee bolster, and door absorber applications to reduce the risk of injury to an occupant during a crash. Automobile manufacturers must meet standards set by the National Highway Traffic Safety Administration (NHTSA) that identify maximum levels of injury to an occupant. The recent NHTSA upgrade to the Federal Motor Vehicle Safety Standard (FMVSS) 201 test procedure(1) for upper interior head impact protection has prompted energy management materials' use in several new areas of affected vehicles. While vehicle evaluations continue, results to date show that energy management foams can be effective in reducing the head injury criterion [HIC(d)] to acceptable government and OEM levels.

In anticipation of complying with European standards for impact protection, an instrument panel design was analyzed to determine A. impact zone boundaries B. impact test velocitiesfor the head of a front seat passenger. Chrysler computer aided design (C.A.D.) surfacing capabilities were utilized in the solution. Early knowledge of impact zone location is important to intelligent design decisions; knowledge of impact velocities aids in performing compliance testing.

The basic theory and the techniques upon which the Air Conditioning Analytical Simulation Package (A/CASP) computer program system was developed is outlined. Methods for simulating car air conditioning components, systems, and cool-down performance by computerized mathematical models are presented. Solution techniques for the models of the evaporator, condenser, compressor, and vehicle are outlined. The correlation of test data and analytical predictions is demonstrated.

THIS PAPER describes balanced-life concept of gear design — in which the gear and pinion are designed to fail simultaneously. An example is presented to show how this concept allows a combination of minimum size and maximum capacity in gas turbine application. Various reasons for failure and factors in long gear life are discussed. The author analyzes the calculations needed and their programming for a digital computer. Calculating gear designs for production is a time consuming, demanding task to do manually. The use of the computer has changed this — and brought about better gear design by making it possible to study more detailed analyses to evolve optimum solutions. This paper was the Sixth L. Ray Buckendale Lecture, presented at the 1960 SAE Annual Meeting.