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Two-poster rig plays a very important role in accelerated durability evaluation in a motorcycle industry, similar to what a four-poster rig does in a car industry. The rig simulates the exact road conditions in the vertical direction through tire coupling by applying feedback control on displacement. On account of its ability to simulate to the exact customer usage conditions, it reproduces the failures realistically as it happens on the field. However, as complete vehicle is required for testing on the rig, the testing happens mostly in the advanced stages of product development. Any failures beyond the concept stage have a huge impact on the development time and cost and the same should be avoided. Therefore, in this paper, a virtual testing methodology is proposed, based on which potential failures on the vehicles can be captured at the concept design stage itself. An ADAMS model of a motorcycle was created.

A numerical method for generating a blockloading profile from a rainflow histogram is described. Unlike previous techniques, this method produces a blockloading profile which, when rainflow-counted, yields a rainflow histogram identical to the original. When implemented with modern data acquisition and signal-processing techniques, this generation method provides a means of developing blockloading test profiles which are correlated with actual service data. This key benefit elevates existing simple testing systems as useful and productive tools despite the emrgence of more complex testing systems.

Product development processes generate large quantities of experimental and analytical data. The data evaluation process is usually quite lengthy since the data needs to be extracted from a large number of individual output files and arranged in suitable formats before they can be compared. When the data quantity grows extremely large, manual extraction cannot be done in a limited timeframe. This paper describes a set of tools developed by MTS engineers to automatically extract the desired information from a large number of files and perform data post-processing. The tools greatly improved both speed and accuracy of the evaluation process during the development of a sound quality-based end-of-line inspection system for seat tracks [1]. It allowed engineers to quickly gather a comprehensive understanding of the relative importance of individual design parameters and of their correlation to the subjective perception of the sound quality of the seat track.

Plastics (polymers) are nowadays clearly a material of choice in all application sectors including in Automobile sector. Automotive manufacturer have relived on new technology for vehicular accessories which are all made-up of different polymers like Acrylonitrile-Butadiene-Styrene (ABS), Poly Carbonates, Poly Methyl Methacrylate (PMMA), Acrylic, glass, resin etc. Although these components offer an impressive range of attractive properties, the effect of climatic conditions on the durability and performance of these materials is not fully understood. The durability, performance and rate of deterioration of these products are all significantly influenced by both the material composition, as well as the climatic conditions to which they are exposed. The degradation/ variation of the mechanical properties of the specimen treated at different environmental/ atmospheric conditions are a primary concern when recommending such a composite for particular use.

Accurate quantification of residual stresses is critical to predict expected fatigue life of the component. Quantification of residual stresses by X ray diffraction method offers substantial accuracy in results as compared to other methods of stress measurements. Depending on component processing and geometry, various stress measurement techniques are used to analyze stress patterns induced by these processing. This paper describes some of the stress measurement techniques by results obtained on two compressor valve (reed) samples which are undergone different processing. First reed sample is analyzed after blanking operation which is expected to give low compressive or tensile stresses whereas second reed sample is analyzed after tumbling operation which is done to get high compressive stresses.

Recently, the use of laboratory-based physical prototype testing as well as the design of virtual models and virtual test equipment has accelerated the pace and quality of racing vehicle development. In particular, the combined use of both virtual and physical testing, when correlated to racetrack improvements, yields a powerful development tool(1), (2),(3). In this study, we applied these techniques from the first stages of the design of a unique Grand Prix racing motorcycle. First, a wire-frame CAD model, then a parametric CAD solid model of the motorcycle was created after preliminary calculations specified the approximate design of structural elements. Subsequently, a virtual dynamic model was created and subjected to a variety of inputs, including sine sweeps, shaped white noise and simulated road time-histories. Loads and other dynamic responses were measured on the virtual model, so that it's design could then be optimized to yield acceptable performance and durability.

The effect of different cold- rolling and cryo-rolling routes on the strength and ductility of Al-6061 alloy was thoroughly investigated. Rolling decreased the grain size and increased the strength according to the Hall-Petch relationship. However subjecting the samples to ageing at different temperatures and for different time period increased the strength and improved the ductility. The ductility was improved due to the rearrangement and even decrease in dislocation density due to recovery and recrystallization during ageing while the strength was maintained due to ageing. Evolution of microstructure was investigated by optical microscopy, scanning electron microscopy. Preliminary hardness measurements coupled with tensile tests indicate the improvement of both yield strength and ductility. The disparity in ultimate tensile strength, yield strength and the elongation to failure with different ageing temperatures and for different time period is determined and discussed.

Rapid development of advanced multi-axial load transducer systems now requires the use of computer-based analytical tools to assist the development engineer optimize the design to meet often-conflicting design targets. This paper presents a case study based on the development of a wheel force load transducer to meet a challenging set of performance goals including accuracy, repeatability, durability and insensitivity to the external environment. The paper also highlights the limitations of some of the current analytical tools when used for load transducer design, and how these limitations can be overcome by cost-effective combinations of analytical performance prediction and physical test confirmation.

Light weighting is significant in for automotive industry as it helps in less fuel consumption and to achieve better performance. Aluminium is a candidate material for light weighting. To design a component made of aluminium material, it is necessary to understand the fatigue performance of the material. In this paper, a study is carried out to understand the fatigue performance of aluminium 6xxx series alloys at an early stage of design without carrying out comprehensive fatigue testing. Coffin Manson Parameters are used to predict fatigue life. This research focusses on determining the gaps in existing models for aluminium alloys by carrying out comprehensive review of various models developed for 6xxx series which uses monotonic tensile data. Two models are developed and the predicted fatigue properties for this class of material are further compared with experimental fatigue, monotonic data and literature.

Automobile industry is shifting towards lighter materials in order to meet the high strength to weight ratio as required for better performance, safety, and environmental concern. The objective of this review is to evaluate and compare the different advanced and light weight materials like advanced high strength steel (AHSS), Magnesium and Aluminium alloys, which will help in selection of appropriate materials for their intended application. In this paper comparison of materials on the basis of their current, applications, limitations, cost, potential future applications and percentage wise use in automotive vehicles are discussed. Solutions and suggestions are discussed to overcome the limitations of materials which will widen their future application. Case studies and charts for cost evaluation of different materials, on the basis of structural properties like stiffness and strength are also discussed.

It is an established fact that virtual knowledge based engineering has revolutionized R & D activities by streamlining processes, ensuring productivity and accuracy. This has resulted in freeing up time for quality interpretational work and decision making for engineering the best of products. Subsequently, homologation is a mandatory requisite activity for product signoff. It certifies the quality of the product and is an important factor in giving the product an authenticity for sale in the market. Homologation entails compliance to regulations existing in form of well-established standards which elaborate systematic and detailed guidelines on conducting physical testing for automotive systems, sub-systems or components for specific vehicle types.

Suspension development is one of the key steps in a complete vehicle development program. Computer simulation and analysis tools such as Multi Body Dynamics (MBD) simulation are used to refine initial concept and suspension parameters. Later on when a physical prototype is available the suspension system can be experimentally optimized at vehicle level. In this paper a new methodology is proposed which integrates virtual and experimental tools so that design, development and validation of the suspension system is carried out in the early phase of the vehicle development cycle with actual suspension components and without the need of a vehicle prototype. With this new approach, the design of any critical suspension components such as dampers can be optimized at the vehicle level. The new approach consists of combining the actual physical components on loading rig in closed loop with vehicle dynamic model running in real time.

In this work, the effect of tool rake angle and cutting speed on residual stresses of tool was studied, the rake angles of 0°, 5°, 10°, 15°, and 20° and a constant clearance (Relief angle) of 8° were used to turn bright mild steel on the lathe machine, A total of 15 experiments were carried out with three different cutting speeds (37.69, 59.37, 94.24 m/min) for each rake angle, keeping the feed rate and depth of cut constant. During the experimentation, the residual stresses were measured using an x-ray diffractiometer. This is all in order to explore the energy savings opportunities during regrinding of tools, useful production time and energy is being wasted due to regrinding or re-sharpening of tools when cutting tools got worn or blunt, selection of the rake angle which generate the optimum residual stresses in the tool, goes a long way in saving these time and energy.

Dual Phase (DP) steels with their high energy absorbing capacity are fast emerging as materials for automotive body applications with improved crashworthiness. The unique combination of high strength and good ductility associated with the DP steels originates from its specially developed microstructure that consists of martensitic islands in ferritic matrix. The high strength and good ductility are expected to give very good resistance to fatigue crack generation and propagation respectively. This paper discusses the fatigue properties determined for a DP steel grade viz. DP 800. The strain controlled fatigue tests were carried out on the un-notched specimens prepared from 1.2 mm sheets to generate E-N curves. The force controlled axial fatigue tests were carried out on two types of specimens prepared from 1.2 mm sheets to generate S-N curves for two Stress Concentration Factors (SCF) viz. 2.5 and 4.4.

Wheel force and moment transducers (WFT) are widely used in vehicle testing and analysis [1], [2], [3]. There are many benefits of using these sensors. To install the transducer, vehicle wheel has to be modified. Transducer mounting adaptors are required to interface the sensor with the modified wheel rim. To study the effect of added mass with wheel force transducers, three vehicles, two types of passenger cars, and one SUV, were instrumented with an MTS spindle wheel force transducer (SWIFT 30A) as well as with regular wheels. The instrumented vehicles were driven on multiple proving ground surfaces with three passes for each vehicle. This experimental data was analyzed using RPC Pro software to assess both per pass variation and data trends from 3 passes without WFT (baseline) and 3 passes with WFT added mass. A validated ADAMS model of a production passenger vehicle, with and without added weight of the wheel force transducers, was also used to assess the added weight effect.

The value of crash simulation has long been recognized by carmakers as an essential tool for vehicle development and certification programs. Driven by the need to minimize time-to-market for new models, cost reduction, and by consumer demand for safer cars and trucks, the industry is moving to newer technologies in crash simulation. Crash simulation provides an inexpensive means to quickly simulate the effects of a barrier crash by reproducing its basic elements - acceleration, velocity and displacement - in a nondestructive test. Crash event timing and accuracy of reproduction are critical performance factors. This paper describes the unique features and capabilities offered by a new generation of crash simulators.

In a developing country like India, Two-wheelers dominate the automotive market with around 80% market shares. In Indian city traffic conditions, driving a two wheeler is a tiresome job. Manual transmission makes this task even further uncomfortable. So an automatic transmission is a better solution. A new automatic transmission system is developed which can reduce fatigue of drivers. Steps of ARIZ (Algorithm for Inventive Problem Solving) were followed. Ideas or concepts for the design were proposed from various fields and were compared for various parameters like size, weight, complexity, manufacturability, feasibility, efficiency and cost. They were also compared with the existing transmission systems. Based upon the results of the comparison, 5 designs were selected and they were analyzed thoroughly. Finally one design was selected.

The use of polymers in automobiles is increasing constantly and this trend is expected to continue. This clearly indicates that polymer are choice of materials in all the application sectors including in Automobile sector. The main properties in selecting the plastics materials as compared to other materials applied in automobiles are the aesthetic of automotive vehicles, their functionality and cost effective solution, as well as fuel efficiency. These materials are offer remarkable range of appealing properties, the effect of climatic conditions on the degradation and performance of these materials is not fully understood. It is necessary to know the variation of the mechanical properties of any polymer component in automobile after exposed to different atmospheric conditions before particular application. Generally when these components are subjected to weathering effects, they are prone to underperform.

Vehicle structural resonance modes are classified generally into rigid and flexible (non–rigid) body modes. During motorcycle testing and development for design validation, it is often useful to understand these modes of vibration. Understanding rigid and flexible body modes helps to improve the ride and handling performance. Understanding the flexible body modes helps to isolate noise, vibration, and harshness (NVH) problems. It can also help to find the root causes of structural durability failures. Flexible body modes can also be annoying or unsafe to the operator. For example, handlebar vibrations may cause numbness in the hands or arms. Flexible body modes also can contribute to motorcycle dynamic instability modes such as the weave instability. Similarly, the rider's ability to see approaching traffic from the rear may be reduced if mirrors are vibrating due to a flexible body mode in the handlebars, frame, or front fork.

Seat system resonant frequencies play an important role in seat design and ride dynamics. So NVH performance of the seats should be assessed from the viewpoint of tactile, acoustic and visual sense. Tactile response is the response of sub-systems, which is induced when the human body contacts steering wheel, footrest or seats. Acoustic response is the behavior of the seat system at the cavity resonance frequencies and visual sense is what we perceive under actual operating conditions. The objective of the present work is to conduct and correlate experimental modal test with FE modal test to identify tactile vibrations. Then the identified main seat modes will be used to set the mode map (seat target) at the stage of full vehicle level. This work will present a practical approach in understanding varied methods and techniques for determining resonant characteristics and for subsequent refinement of FE model.