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A state-of-the-art review of the technical meaning and application of the term ‘maneuver’, used by the U.S. Army and ground vehicle engineering communities, was performed with regard to various military activities, including modeling and simulation (M&S), to focus on the value and applicability of the term to military vehicle dynamics. As shown, U.S. military doctrine has built through history and experience a unique concept of maneuver-in-general and its application in U.S. Army unified land operations. Yet, the term ‘maneuver’ needs further technical categorization and characterization for the purpose of dynamics of military unmanned ground vehicles (UGVs) and vehicle design for maneuver. While the NHTSA and SAE standards and definitions provide solid foundations for M&S of cars and trucks to enhance the safety of those vehicles (manned and autonomous), occupants, and pedestrians on roads, the standards cannot address all needs of military vehicles in maneuver.

Supervised, unsupervised and active learning techniques can be used to develop prognostics and diagnostics in connected vehicle networks, where a wide variety of sensors are available for data collection. However, constraints placed by the on-board equipment, vehicle network, time, and human resources limit the amount of sensor data and labels for machine learning. When no prior information about the data distribution or domain knowledge is available, it becomes a challenging task to collect limited and relevant data to train a machine learning model matching the desired performance threshold. To tackle this challenge, techniques such as experimental design, feature selection, and active learning can be applied, and the data collection process can be advanced to a closed-loop system where new data collection decisions are made based on the feedback from collected data.

There are many opportunities for lightweighting with ductile iron castings. Current research shows ductile iron castings free of massive carbides can be achieved at under 2 mm (0.080”) through alloying or process changes which means that significant weight reductions are possible. In fact, for aluminum components over 4 mm thick, ductile iron may provide lightweighting opportunities at a cost savings. However, the conventional guidelines for casting design are inadequate when using ductile iron at dimensions less than the typical machine stock. This paper will discuss the current research on thin walled ductile iron, when it is superior to aluminum, design considerations, and current DOE SBIR funded research efforts to address these inadequacies. Research results on efforts to quantify and improve surface roughness in expanded polystyrene for lost foam casting are also discussed.

An automotive cockpit module is a complex assembly, which consists of components and sub-systems. The critical systems in the cockpit module are the instrument panel (IP), the floor console, and door trim assemblies, which consist of many plastic trims. Stiffness is one of the most important parameters for the plastic trims' design, and it should be optimum to meet all the three functional requirements of safety, vibration and durability. This paper presents how the CAE application and various other techniques are used efficiently to predict the stiffness, and the strength of automotive cockpit systems, which will reduce the product development cycle time and cost. The implicit solver is used for the most of the stiffness analysis, and the explicit techniques are used in highly non-linear situations. This paper also shows the correlations of the CAE results and the physical test results, which will give more confidence in product design and reduce the cost of prototype testing.

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.

It is postulated that the value-adding intellectual activity in an enterprise can be formulated as an engineering design problem, using axiomatic design. Axiomatic design formulates a decomposition structure that includes four domains: customer, functional, physical, and process. Knowledge exists within the entities in domains and in the relation between the entities in adjacent domains. Once an entity has been identified in one domain, a properly designed knowledge management system can suggest all the known solutions in the adjacent domains, and the interactions between the domains, along with details about how well these solutions work.

Anthropomorphic Test Devices (ATDs) or crash test dummies are an integral part to running automotive safety tests. ATDs require periodic dynamic verification and certification tests to ensure they are responding as designed prior to use in a vehicle crash test. In safety test laboratories, ATD certification has to be completed efficiently and reliably. For high volume safety testing, a PC based software package was required to conduct and manage ATD certification tests efficiently. This paper outlines a modular application that performs the following functions: conducting ATD verification tests, processing test data, generating certification reports, and managing dummy inventories and scheduling. The application seamlessly integrates off-the-shelf software with visual C++, ASP, and Oracle.

This paper introduces a comprehensive system of production planning for mass customization of non-rotational parts. The combined features are defined based on the concept of part families. The process parameters are associated with the feature parameters so that a rapid production planning can be achieved for product design changes. Setup planning is carried out based on both the best practice knowledge in industry and the analysis based generation of setups. Manufacturing resource, fixture design, and tolerance issues are considered in the system. The cycle time estimation and standard documentation are included in the system.

Microcellular urethane jounce bumpers are used in many automotive suspension systems. This study experimentally determined the dynamic force, acceleration, displacement, dynamic stiffness, and natural frequencies of constant-cross-section bumper samples made with microcellular urethane materials of three different densities. Four impact energy levels were used. Dynamic responses were analyzed in both time and frequency domains. The dynamic displacement, acceleration, and force responses are nonlinear and the dynamic stiffness exhibits a hysteresis loop. A mathematical model for dynamic stiffness and damping is developed. Average dynamic stiffness proved to be approximately twice that of the static stiffness for the same materials as independently measured over the same range of deflection by the bumper manufacturer. Natural frequencies of the sample bumpers were measured by two methods with close correlation of the results which ranged from 320 to 420 Hz for the samples tested.

A systematic life cycle management (LCM) approach has been used by Chrysler Corporation to compare existing and alternate hydraulic fluids and lubricating oils in thirteen classifications at a manufacturing facility. The presence of restricted or regulated chemicals, recyclability, and recycled content of the various products were also compared. For ten of the thirteen types of product, an alternate product was identified as more beneficial. This LCM study provided Chrysler personnel with a practical purchasing tool to identify the most cost effective hydraulic fluid or lubricant oil product available for a chosen application on an LCM basis.

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.

This study analyzes the vibration characteristics of the valve train of a 2.0L SOHC Chrysler Corp. Neon engine over a range of operating speeds to investigate and demonstrate the advantages and limitations of various dynamic measurements such as displacement, velocity, and acceleration in this application. The valve train was tested in a motoring fixture at speeds of 500 to 3500 camshaft rpm. The advantages of analyzing both time and frequency domain measurements are described. Both frequency and order analysis were done on the data. The theoretical order spectra of cam displacement and acceleration were computed and compared to the experimental data. Deconvolution was used to uncover characteristic frequencies of vibration in the system. The theoretical cam acceleration spectrum was deconvolved from measured acceleration spectra to reveal the frequency response function of the follower system.

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.

Hand dismantling of certain automotive parts has been an accepted process to remove high value materials, but in large scale recycling this may not be economical. In plastics, a pure non contaminated material stream is critical for maintaining high material values and this means designing plastic parts that can be machine separated. One candidate for separating the plastics in vehicle subsystems such as instrument panels and door trim panels is density separation. In order to better understand what processes are required to develop design requirements for automated plastic separation methods Chrysler and the Vehicle Recycling Partnership have undertaken a major materials separation study with MBA Polymers. In this paper, we describe the material separation methods and the application of these methods to three automotive interior assemblies.

In many instances, automotive companies wish to create both a left-hand drive and a right-hand drive version of the same vehicle. When the vehicle has relatively low sales volumes, it is imperative to reduce investment costs wherever possible. One successful - if challenging - way is by producing the instrument panel system for both versions off the same tooling. This feat was accomplished in the case of the '97 Jeep® Wrangler, saving the company approximately $7 million.

Environmental costs are a delayed financial burden that result from product decisions made early in the product life cycle--early material choices may create regulatory and waste management costs that were not factored into the acquisition cost. This paper outlines a step-wise approach to determine decision points; environmental, health, safety and recycling (EHS&R) cost drivers that affect decisions; and sources of information required to conduct a Life Cycle Management (LCM) review. Additionally, how LCM fits into the larger concurrent engineering framework is illustrated with an electrocoat primer example. Upstream and downstream supply chain processes are reviewed, as well as organizational challenges that affect the decision process.

In recent years, strict weight reduction targets have pushed auto manufacturers to use lighter gauge sheet steels in all areas of the vehicle including exterior body panels. As sheet metal thicknesses are reduced, dentability of body panels becomes of increasing concern. Thus, the goal becomes one of reducing sheet metal thickness while maintaining acceptable dent resistance. Most prior work in this area has focused on quasi-static loading conditions. In this study, both quasi-static and dynamic dent tests are evaluated. Fully assembled doors made from mild, medium strength bake hardenable and non-bake hardenable steels are examined. The quasi-static dent test is run at a test speed of 0.1 m/minute while the dynamic dent test is run at a test speed of 26.8 m/minute. Dynamic dent testing is of interest because it more closely approximates real life denting conditions such as in-plant handling and transit damage, and parking lot damage from car door and shopping cart impact.

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.

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.