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This paper reports on the efforts of the initial phase of the IMPACT program to define the underlying structural theory behind selecting the proper material(s) to reduce weight in the most efficient, cost-effective manner. Following this initial phase, the IMPACT program will proceed to design and build, optimized, proprietary, full vehicle platform prototypes that achieve up to a 25 percent weight reduction total without compromising any customer-driven vehicle attributes. Most importantly, the materials and technologies selected must be implementation ready for high volume, low cost, dual-use applications. The purpose of the initial phase and an in-depth discussion on which material properties should most influence material selection are presented.

This paper presents the results of achieving compliance with established and proposed Occupational Safety and Health Administration (OSHA) rulemaking, reducing musculoskeletal disorders (MSDs), and improving efficiency for rail and bus transportation providers by implementing an organizational-wide ergonomics program. Specifically, potential hazards affecting bus mechanics are identified, and methods to reduce exposure are detailed.

This paper describes the ergonomics program at Freightliner and how it is integrated in the engineering and design process. It will also describe how we use advanced technologies such as 3-D Digital Human Modeling with RAMSIS and how these are applied to the design process to ensure optimized ergonomics in our trucks.

Few studies have systematically examined the effects of truck and bus workstation geometry on driver posture and position. This paper presents methods for determining drivers' postural responses and preferred component locations using a reconfigurable vehicle mockup. Body landmark locations recorded using a three-dimensional digitizer are used to compute a skeletal-linkage representation of the drivers' posture. A sequential adjustment procedure is used to determine the preferred positions and orientations of key components, including the seat, steering wheel, and pedals. Data gathered using these methods will be used to create new design tools for trucks and buses, including models of driver-selected seat position, eye location, and needed component adjustment ranges. The results will also be used to create accurate posture-prediction models for use with human modeling software.

Body size, or anthropometric, data can be applied to the design of truck cabs in a number of ways. The traditional approach involves specifying single dimensions with a specific percentile (e.g., 95th percentile Seated Eye Height). However, anthropometric dimensions vary independently, so specifying multiple dimensions can result in impossible design targets. We propose the use of multivariate accommodation models that have been successfully used in aircraft cockpit design. This approach allows the simultaneous inclusion of a larger number of dimensions while simplifying design by limiting the number of actual test cases. We use a sample analysis to show how this approach can be usefully applied to truck cab design.

Modularization does not only give economic and manufacturing advantages, it also provides a basis for development of a first class ergonomic driver environment. Scania Commercial Vehicle AB has a long tradition in producing highly modularized products and throughout the years Scania has gained a reputation of having a well-planned and flexible driver interface. The key to this has been a structured system, which has adaptation capabilities, and to use the strong points of modularization to gain functionality. By using versatile and functionally unique modules, a palette of functionality is formed. This palette provides the possibility to meet different drivers needs and preferences with good ergonomic solutions.

The 21st Century Truck Initiative represents the premier partnership between government (Departments of Defense, Army, Energy, Transportation and the Environmental Protection Agency) and the U.S. trucking and supporting industries in seeking to develop and demonstrate commercially viable advanced technologies for trucks in the 21st century. At the request of senior leadership within the U.S. Departments of Defense and the Army, the Tank-automotive and Armaments Command's (TACOM) National Automotive Center (NAC), located at TACOM's Tank-Automotive Research, Development & Engineering Center (TARDEC), spearheaded the creation of this government-industry partnership to pursue the necessary leap-ahead technologies. By teaming the research and development efforts of government and industry, the partnership will improve fuel efficiency, increase safety, reduce owning and operating costs, and reduce emissions, while maintaining or enhancing the performance of military and commercial trucks.

Hybrid electric propulsion is a viable, realistic, near-term technology that can dramatically increase the fuel efficiency of commercial and military ground vehicles. Hybrid vehicles also benefit from exhaust emission reductions and the availability of an on-board source of mobile high power electrical energy for auxiliary systems.

Modern natural gas-to-liquids (GTL) conversion processes (Fischer-Tropsch liquid fuels (FTL)) offers an attractive means for making synthetic liquid fuels. Military diesel and jet fuels are procured under Commercial Item Description (CID) A-A-52557 (based on ASTM D 975) and MIL-DTL-83133/MIL-DTL-5624 (JP-8/JP-5), respectively. The Single Fuel Forward (single fuel in the battlefield) policy requires the use of JP-8 or JP-5 (JP-8/5). Fuel properties crucial to fuel system/engine performance/operation are identified for both old and new tactical/non-tactical vehicles. The 21st Century Truck program is developing technology for improved safety, reduced harmful exhaust emissions, improved fuel efficiency, and reduced cost of ownership of future military and civilian ground vehicles (in the heavy duty category having gross vehicle weights exceeding 8500 pounds).[1]

To reach its objective of reducing vehicle fuel consumption by 50 percent, the development of the 21st Century Truck (21T) will address all the aspects of truck design contributing to the achievement of that goal. [1] This paper will address one of these aspects, specifically vehicle parasitic loss reduction with special emphasis on drive train losses, concentrating on the potential benefits of replacing mechanical coolant (water) and oil pumps with electrically powered pumps.

Recently safety systems for the commercial vehicle have been rapidly developed. However, we still have many problems in the vehicle stability and the braking performance. Especially, a commercial vehicle may meet a dangerous braking condition when the vehicle is lightly loaded or empty and when the road is wet or slippery. Under these conditions, the truck can spin out or the tractor can jackknife or the trailer can swing out. To design the air brake system for the commercial vehicle, since the air brake system has many design variables, there must have been intensive researches on a method how to prevent dynamic instability and how to maximize vehicle deceleration. In this study, mathematical models of the tractor-semitrailer and the air brake system including an ABS controller have been constructed for computer simulation. Also, simple examples are applied to show the usefulness of the program.

The primary objective of this paper is to develop a model that accurately represents the dynamics of air flowing through the components of a pneumatic system configuration, which is common in many heavy duty vehicle applications, that eventually translates into braking force. This objective is met using the dynamic compressible airflow equations, which describe flow through an orifice. These equations are coordinated to describe the directional motion of dynamic airflow as commanded by the driver at the foot-pedal and as modified downstream by a modulator to facilitate ABS activity. The solenoid actuated relay valve also includes the motion dynamics of a piston in the existence of hysteresis and coulomb friction type built-in non-smooth nonlinearities. The adoption of an isentropic process, as opposed to the more general case of polytropic behavior, is experimentally determined to suffice for accuracy while yielding significant mathematical convenience.

Effective linear and nonlinear drum brake system FEA (finite element analysis) models have been developed. Such models can help engineers understand many drum brake related issues, such as lining wear and mechanical and thermal instability. The pressure distribution at the drum and lining interface is an important piece of information in drum brake design. Besides the accurate prediction of the shoe factor, the models can be used to guide designs for improving brake efficiency, reducing component weight and enhancing durability. Progress is also being made in developing hybrid models that integrate FEA models with other analysis techniques. This approach offers engineers easy-to-use design tools. The integrated design and analysis approach will help product design and development by reducing cycle time, cost and improving product quality.

A backpropagation through time algorithm was used to model and predict the rollover of a tank truck carrying varying liquid volumes, traveling at various speeds, and performing a number of steering maneuvers of up to 12 seconds duration. The training and testing data sets were built with data produced by simulations using first principle models. Because neural networks have trouble predicting behaviors beyond the boundaries of their training sets, the training set was weighted with 5 per cent of the input examples involving vehicle rollover due to sloshing. The network outputs under test data sets produced very strong correlations with first principle roll simulations in both rollover and non-extreme steering maneuvers.

The need for new symbols for controls, indicators and tell-tales is steadily increasing due to the rapid technical development in modern vehicles. When creating new symbols it is important that the different aspects, which influence symbols, are accounted for. What should a symbol depict? The actual thing that happens or the objects involved in the process? The understandability of a symbol is important and the utmost goal is that a symbol should be self-explanitory. When using a symbol it is also important that it is used in the correct context. Many times the language or cultural background of the user can influence the understandability. Testing the understanding of symbols in a survey form is an important tool in creating good symbols. These and several other factors involved in the creation of symbols, together with what the future will bring, are covered in this paper.

Communication is vital to the successful delivery of freight. A product that uses the latest communications technology, and makes that technology easily accessible to a driver would be a great benefit to the trucking industry. This paper focuses on the iterative design process of such a product called the Truck Productivity Computer™ (TruckPC). The TruckPC is a combination of an audio system, which includes radio, CD and weather, and an open platform communications and computing system. This paper discusses the driver-centered design process that was used in the development of both software and hardware interfaces. Topics discussed include the human factors guidelines that provided a basis for early design values and testing that concerned the design of the user input modes (buttons, knobs, speech recognition) and output modes (display, division of information on the display, text-to-speech synthesis).

Vehicle interior harmony has drawn increasing attention from customers in recent years. Kansei Engineering is an effective approach to quantify the relationship between design parameters and customer perceptions of the product. This article is a continuation of our previous study on commercial truck interior harmony. Herein, we investigated the customer perception of the visual aspects of commercial truck door interior design using classification methods. This article describes how these visual impressions are related to design elements using quantification theory, a commonly used method in Kansei Engineering. The results reveal that trim material, shape, color, window shape, and map pocket are design elements that strongly affect the perception of elegance and preferences of truck drivers. The results also showed a significant difference between the perception of the truck drivers and design engineers.

The distribution of the braking forces between axles has influence to the vehicle's braking ability, braking behaviour, and safety in traffic. In designing of brakes it is important to meet the most essential demands which are operating environment, structural properties of a vehicle, basic dimensioning of the brake mechanisms, and the controllability of braking forces as well as regulations on brakes. This paper introduces a study of the results during braking of 2- and 3-axle lorry and concentrates on the fulfilment of the braking force distribution according to the regulations in Finland. The friction requirements are compared with the regulations.

The design and evaluation of seating has been limited by the available technologies to measure the mechanical interaction between a seat and its user. For many years, representation of the seated torso has been by two standardized measurement manikins from the American National Standards Institute (ANSI)1 for office seating and the Society of Automotive Engineers (SAE)2 for vehicle seating. Most office and automotive seat backs recline about a single point; this motion can be measured with the available manikins. However, both the ANSI and the SAE manikins do not represent the natural anatomical movements of the upper torso (thorax) relative to the lower torso (pelvis) that occur with spinal articulation. Current tools that are useful for seat design and evaluation include the biomechanical models3,4 and experimental test methods5, 6,7 that have been developed at Michigan State University's (MSU) Biomechanical Design Research Laboratory (BDRL).

In the heavy truck market, suspension seating has evolved through research in the areas of comfort durability, and vibration exposure analysis. These areas are under constant investigation and development for the production of a suspension seat that will accommodate a larger range of occupants more comfortably, will possess increased durability, and will provide the drivers with more control of their driving environment. Some comfort technologies under current investigation for the heavy truck market that will be discussed include electromyography (EMG), benchmarking, pressure mapping, and field evaluation. Current durability research includes field data acquisition, fatigue analysis, and accelerated simulation testing. Vibration exposure research aims to develop improved occupant isolation from vehicle and road vibration. The research conducted in these areas is leading toward improvements in the development and design of seating in the heavy truck market.