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This paper is a status report of the New Car Assessment Program's data on light trucks. In 1983, the New Car Assessment Program (NCAP) began including light trucks in its testing program. To date, data on light trucks, vans, and multipurpose vehicles are inadequate to draw conclusions. Because of consumer demands for crashworthiness information on these vehicles, the National Highway Traffic Safety Administration will continue to expand its NCAP database on these vehicles in subsequent years.

This paper presents the method applied in the development and optimization of a powertrain driveshaft for a Light Truck Diesel. The focus of this optimization is to reduce the vibration consequently improve the NVH (Noise and Vibration Harshness) quality of the vehicle. The paper describes the basic 6sigma methodology, inputs required to perform the 6Sigma method, the experimental work required. The experimental results for an optimized version are also presented and compared to the original one.

The Budd Company designed, prototyped, and laboratory/field tested a fiberglass leaf spring for a Ford Econoline Van. Prior to design and materials selection, extensive development work was conducted on fiber/resin systems. Computer design programs were written which would accept conventional leaf spring parameters and output nominal stresses, tooling data, and weights for a selection of unidirectional monoleaf configurations. Extensive prototype testing was conducted on a laboratory leaf spring fatigue tester equipped with a simultaneous brake torque simulator (for attachment testing). Field testing was conducted on urban roads and at Ford and G. M. Proving Grounds to correlate materials, design, and laboratory-field data.

New relationships are being developed between original equipment manufacturers and their suppliers. Early supplier involvement, long-term relationships and simultaneous engineering are commonplace in today's new vehicle development. Simultaneous engineering is the synthesis of the product design, analysis, development, test, process, reliability and manufacturing functions. It results in a synergy between the OEM and their first tier supply base and, in turn, second tier suppliers. The scope of this paper is the development and implementation of the new frame designs for the General Motors 1988 GMT 400 product line.

During the last decade, political and economic forces have prompted the United States Government to issue regulations establishing minimum fuel economy standards for trucks. In response to this challenge, powertrain engineers took steps to design more efficient powertrain components. These components had to be matched to achieve optimal vehicle performance and fuel economy. It was the responsibility of the Powertrain Optimization Engineer to develop vehicle simulation programs and analytical methods, which could be used in powertrain matching studies. The purpose of this paper is to explain what role the Powertrain Optimization Engineer plays in the overall vehicle design process. Also, its purpose is to describe the analytical methods used by the POE to design powertrains that achieve a reasonable balance between good fuel economy and acceptable performance.

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.

The demands for safe, reliable, lighter, energy efficient and competitively priced products put a new emphasis on predictability of rolling bearing performance. This has prompted designers and engineers to estimate bearing life and optimize the design by taking into account different market requirement. Estimation of actual dynamic bearing load and life for specified class of vehicle depends upon various factors such as usage pattern, vehicle Gross Vehicel Weight (GVW), type of roads, speed, driving pattern, geographical area, ambient temperature, acceleration etc. For estimation and prediction of life of the particular wheel bearing type it is required to identify and measure customer usage loads for different targeted markets. The measurement maps all the affecting parameters to arrive at a generalized duty cycle for bearings. A software tool is developed to predict the bearing life with these measured inputs and this enables designers to optimize bearing designs for target markets.

New test procedures for the control of light vehicle noise have been under discussion recently in Europe and America as there is some dissatisfaction with the established procedures. This paper sets out the origins and characteristics of light vehicle noise and reviews the data available on light vehicle operation. It is then shown how the two opposing philosophies of a maximum noise test and of a test representing average operating conditions develop from this background. An appendix gives details of many test procedures that have been used or proposed for light vehicle noise since the original German and proposed United Kingdom legislation of 1935. Six of these procedures have been chosen for detailed evaluation, three maximum noise and three representative driving tests. Data from these tests are used to illustrate the practical as opposed to the theoretical effects of the two philosophies.

Body in white (BIW) forms a major structure in any automobile. It is responsible for safety and structural rigidity of the vehicle. Also, this frame supports the power plant, auxiliary equipments and all body parts of the vehicle. When it comes to judging the performance of the vehicle, BIW is analyzed not only for its strength and shape but also the weight. Light weight BIW structures have grown rapidly in order to fulfill the requirements of the best vehicle performance in dynamic conditions. Since then lot of efforts have been put into computer-aided engineering (CAE), materials research, advanced manufacturing processes and joining methods. Each of them play a critical role in BIW functionality. Constructional designing, development of light materials with improved strength and special manufacturing practices for BIW are few research areas with scope of improvement. This paper attempts to review various factors studied for BIW weight reduction.

In an off-road vehicle, Vehicle Structure plays a major role in passenger safety, Aesthetics, Durability, through a validated construction of canopy structure. This structure is to maintain the shape of the vehicle and to support various loads acting on the vehicle. In present market a safe, Durable, Robust, Waterproof, Noise less, Light weight and cost-effective off-road vehicle will always be a delight for any customer. However, the current conventional way of Soft top vehicle structure use metal brackets and formed sheet parts to create a structure to retain the canopy shape in place. These conventional structures are often heavier and would have many demerits such as heavy weight, Corrosion, Risk of canopy tear due to metallic structure edges and inappropriate draining, water management. Considering this we replaced the heavy metal brackets in to blow molded plastic parts.

Front suspension frame is an integral part of automobile chassis which acts as a major load carrying structural member and connects different suspension components with body. It provides the required stiffness for achieving desired vehicle dynamics performance. Acting as a major road load path from tire to body, it also acts as a mounting base for suspension arm, steering and compression rod. Considering the competitive market conditions, increased fuel efficiency demand along with enhanced structural durability, it is important to evaluate suspension frame for stiffness and durability using Computer Aided Engineering (CAE) methodology so as to reduce product development time and First Time Right cost effective design. In this paper focus is given on CAE methodology used to design a light weight tubular kind of suspension frame for light commercial vehicle with stiffness comparable to conventional sheet metal suspension frame and similar durability performance with reduced weight.

The automotive industry needs sustainable seating products which offer good climate performance and superior seating comfort. The safety requirement is always a concern for current seating systems. The life of the present seating system is low and absorbs moisture over a period of time which affects seat performance (cushioning effect). Recycling is one of the major concerns as far as polyurethane (PU) is concerned. This paper presents the development of an alternative material which is eco-friendly and light in weight. Thermoplastic Polyolefin (PO) materials were tried in place PU for many good reasons. It is closed cell foam which has better tear and abrasion resistance. It doesn't absorb water and has excellent weathering resistance. Also it has a better cushioning effect and available in various colours. Because of superior tear resistance, it is possible to eliminate upholstery and would reduce system level cost.

Usually conventional iterative methods of optimization will consume more time to optimize the given design. Mostly, it becomes very difficult if multiple loads are acting on the structure contradicting each other. CAE based optimization technique becomes more useful in such cases to optimize the given design and achieve weight reduction. Optimization methods offers guidance to expedite solutions, resulting in a substantial reduction in product development time. Nowadays, optimization became inevitable part among the virtual validation processes of design in industries. A wide range of optimization methods have been effectively employed in the design of tractor components, especially mounting brackets, chassis and skid housing for the development of off-road vehicle. Based on the design stage, various optimization techniques were followed i.e. Topology, size and shape. Depending upon the available analysis time & Design freedom, determines the type of optimization approach to be used.

Light duty truck fuel economy trends from model year 1975 through 1984 are examined, with special emphasis placed on model year 1984. Actual production volumes are given for model years 1975 through 1982. Data for 1983 and 1984 model years include EPA estimates of sales, in which projected sales data submitted by manufacturers were adjusted using the same procedure as described in (1)*. For fuel economy trend analysis, a modified truck classification system is presented and discussed. In addition, the model year 1975 to model year 1979 light truck data bases have been updated to include those trucks with gross vehicle weights (GVWs) between 6000 and 8500 lbs; accordingly the paper treats all model year trucks from 1975 through 1984 as 0-8500 lb GVW fleets. This paper, along with the passenger car fuel economy trends paper (1), gives a complete picture of fuel economy trends through 1984. Combined car/truck fleet analyses are presented in Appendix A.

The use of Aluminum Metal Matrix Composites (MMC's) is becoming a viable solution to help meet the new regulations of the medium to heavy-duty truck markets. The objective of this paper is to present both analytical and dynamometer data that demonstrate the damage tolerance of a selectively reinforced Aluminum MMC brake drum. In particular, dissimilar coefficients of thermal expansion (CTEs) between the MMC and Aluminum portion of the drum results in favorable compressive stresses in the Aluminum. This state of stress facilitates the slowing of crack growth for flaws whose depth reaches the boundary between MMC and Aluminum. This paper will present an analytical study utilizing finite-element models to predict stress levels in a drum subject to thermal and mechanical loading. Examination of the stress-fields for braking events at room temperature and elevated temperature provides evidence of the aforementioned compressive stresses in the Aluminum portion of the drum.

Rising fuel costs, shorter stopping distance requirements, and the growth in hybrid vehicles all lead to an increased demand in lightweight vehicle components. Changing market needs generate innovative products. One innovative product is a lightweight aluminum metal matrix composite (MMC) brake drum that is substantially lighter than the traditional cast iron product. The objective of this paper is to present the lightweight brake drum using both analytical and dynamometer data to demonstrate the effectiveness during speed sensitivity testing. Thermal analysis tools were developed to predict brake temperatures. These predictions utilize system parameters and braking event characteristics to create realistic predictions of temperature, which have been validated with dynamometer testing. This paper will also present dynamometer data that shows the effectiveness of braking events at varying brake speeds and system pressures.

As the automotive industry focuses on fuel-efficient and eco-friendly vehicles along with reducing the carbon footprint, weight reduction becomes essential. Composite materials offer several advantages over metals, including lighter weight, corrosion resistance, low maintenance, longer lifespan, and the ability to customize their strength and stiffness according to specific loading requirements. This paper describes the design and development of the Rear Under Run Protection Device (RUPD) using composite materials. RUPD is designed to prevent rear under-running of passenger vehicles by heavy-duty trucks in the event of a crash. The structural strength and integrity of RUPD assembly are evaluated by applying loads and constraints in accordance with IS 14812:2005. The design objective was to reduce weight while maintaining a balance between strength, stiffness, weight, manufacturability, and cost.

The increasing demand for engines with higher efficiency, reduced fuel consumption and high power density is driving the future engine technologies in the direction of downsizing and reduction of number of cylinders, especially for Otto engines. Specifically the Power Cell Unit (PCU) components are of extreme interest due to its potential for weight and friction reduction. To cope with these demands a new lightweight connecting rod design for flex fueled engines was developed. The combination of thinner web thickness and bushingless small end (coated and profiled), through the optimization by Finite Element Analysis (FEA) simulation, enabled on the new lightweight design a weight reduction of 25% maintaining safe connecting rod fatigue limits in a studied flex fueled engine. The connecting rod bearings were evaluated using Elasto-Hydrodynamic Lubrication (EHL) simulation, and demonstrated suitable results. The connecting rod material selected was the premium 46MnVS6 forged steel.

In this paper the lightweight design and construction of road vehicle aluminum wheels is dealt with, referring particularly to safety. Dedicated experimental tests aimed at assessing the fatigue life behavior of aluminum alloy A356 - T6 have been performed. Cylindrical specimens have been extracted from three different locations in the wheel. Fully reversed strain-controlled and load-controlled fatigue tests have been performed and the stress/strain-life curves on the three areas of the wheel have been computed and compared. The constant amplitude rotary bending fatigue test of the wheel has been simulated by means of Finite Element method. The FE model has been validated by measuring the strain at several points of the wheel during the actual test. From the FE model, the stress tensor time history on the whole wheel over a loading cycle has been extracted.

High definition (HD) maps can provide comprehensive and accurate knowledge of the environment for highly autonomous vehicles. However, HD maps have large data volumes, which pose high demands on data acquisition, analysis, and storage. To balance data volume and map definition between HD maps and low-accuracy road network maps, this paper is focused on the construction of lightweight HD maps for autonomous vehicles running with non-paved roads. Firstly, we introduce the representation of a lightweight HD map which contains several special elements, e.g., operating areas, parking lot, junction, borders, and centerlines, to describe the closed environment. Then, we propose a border generation algorithm and a border expansion algorithm to find the real border of the map and construct the drivable area. Meanwhile, a two-step method is proposed to extract the centerline of the road. An experiment is conducted to demonstrate the effectiveness of the proposed algorithms.