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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.

The paper describe investigations on the vibration characteristics of a gasoline engine due to piston slap and a diesel engine due to combustion. Engine parameters and vibration data were recorded and time series signals were obtained. The effect of speed, load and other engine parameters on vibration is investigated. Vibration due to piston slap is analysed with reference to major-minor thrust relationship, cylinder to cylinder variation, piston-slap force diagram and vibration-frequency curves. The experimental results suggest that all reciprocating engines would exhibit a complex vibration pattern due to piston slap at harmonic series of discrete frequencies, and the reason for this is analysed. The vibration transmitted by engine structure in response to the in-cylinder pressure development is termed here as ‘Vibration due to Combustion’ and is assessed from the spectrum of the Combustion Pressure curves and their derivatives in terms of time.

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.

This study was carried out to evaluate the variation in performance and emission characteristics of a multi cylinder Multi-point Fuel Injection (MPFI) automotive Spark Ignition (SI) engine after incorporating an additional manifold for gas injectors to throttle body. To install gas injectors for Compressed Natural Gas (CNG)/Hydrogen-CNG (HCNG) operation throttle body of the engine was modified using a novel manifold. The performance and emission characteristics of the existing throttle body and the new throttle body configuration were evaluated. The parameters studied were Manifold Air Pressure (MAP), Torque and Emissions (HC, CO, CO2, and NOx) for gasoline operation. The influence of installing new manifold on these parameters was evaluated. It was important to evaluate the degree of variation of the parameters on the gasoline operation so that the addition of new manifold for gas operation could be validated. The measurement was carried out at wide open throttle.

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.

In recent studies, the health implications of ultra fine particle emissions from vehicles have been investigated in a number of international studies. The adverse health effects are not only dependent on total particulate mass but also on other attributes including size, number and surface area of the particles. These ultra fine particles cause more adverse effect than larger particles. With this need UNECE GRPE had launched a Particulate Measurement Program (PMP) to formulate the regulation to control both particulate mass and number of ultra fine particles. These new regulations are applicable to the diesel and gasoline direct injection passenger cars and heavy duty engines of Euro-V/VI technology. However, at present the other vehicle categories and alternate fuels are not been covered. Limited experiments have been carried-out on the in-use vehicles which are with old technologies.

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.

Environmental pollution is of great concern; hence the emission norms for the diesel engines are made more stringent. The purpose of this work is to develop a process to optimize the FIS parameters and select a most suitable FIS by simulation to meet the target emissions. During the combustion optimization exercise of diesel engine, different hardware combinations like injector, HPP etc are matched through testing to achieve the required performance and emissions. The process requires the real testing of the engine on engine dynamometer with various hardware combinations, which is expensive and time consuming. A simulation model of diesel FIS is constructed using ‘AVL Hydsim’. The model is validated by comparing the predicted and the experimental results. The validated model is used for further work. Critical parameters were listed based on the sensitivity analysis on the base model.

Finite Element simulation of a lower extremity model is used to (1) determine which of the muscle parameters maximum force capacity (Fmax), initial activation levels (Na) and maximum muscle contraction velocity (Vmax) affect ligament strains the most and (2) to identify which muscles affect the knee response the most in low speed, just below the knee, lateral impact. Simulations have been performed with Fmax, Na and Vmax varying from their reference values. Sensitivity of ligament strains to variation in muscle parameters has been studied. It is observed that knee response is more sensitive to Fmax and Na than Vmax. Amongst the muscles varied, reduction in the Fmax and the Na in the hamstring and the gastrocnemius muscles affects the knee ligament strains the most. The hamstring parameters significantly affects the ACL, the PCL as well as the MCL strains whereas, change in the gastrocnemius parameters affects only the MCL strain.

Anthropometric data of a country is vital database for automotive design and other design applications. It is also an important parameter in population studies. Most developed countries have invested resources over the years to develop such a database and this information is accessed by many OEMs and major Design Houses. However, an updated and comprehensive Anthropometry of Indian Population is largely unknown. In the past, a few institutions have done projects to bring out a picture of the Indian Anthropometry. However, keeping in view the rapid industrialization and increase of India-specific designs which require an access to latest Anthropometric database, the project “SIZE INDIA” has been initiated. For the first time in India, a state of the art 3D Whole body scanner technology has been used and thereby large volume of data has been generated in a very short span of time.

Automotive Industry Standard (AIS)-031 specifies the requirement of strength of large passenger vehicles in case of rollover. In India the certificate is granted after the successful completion of rollover test of the vehicle as per AIS-031. Complete vehicle is used for rollover test in which the vehicle is tilted laterally in the ditch of 800 mm. Such tests with complete vehicle are costly and unaffordable to small bus body builders. So according to Annex 2 of AIS-031, manufacture can carryout rollover on body sections of the vehicle. This is an equivalent approval method which is less costly compared to rollover test on complete vehicle. It requires detailed study of superstructure and selection of weakest body sections from the given superstructure of bus, which in turn requires mass and energy calculation of body section. For doing rollover analysis using body section, bus is selected which has already passed a full-rollover test.

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.

Compressed Natural Gas (CNG) has been regularly used as a fuel for transportation sector. Hydrogen has been found to posse the unique feature close to that of a zero emission vehicles. Mixture of CNG and Hydrogen can further improve the performance and emission characteristics of a CNG-fuelled engine. This paper describes the results of an experimental study carried out on a spark ignition engine in the Engines and Unconventional Fuels Lab of Centre for Energy Studies in Indian Institute of Technology, Delhi. It has been observed that addition of 10% and 15% hydrogen on energy basis to operate a CNG-fuelled engine significantly improves the performance and emission characteristics of the system.

Biodiesel can be used as a supplementary fuel in diesel engines and it will be implemented in automotive fleets and power genset diesel engines in near future in our country. There is lot of studies available in literatures on use of biodiesel blends in unmodified diesel engines. However, it is reported NOx emission and SFC increases with the blends in the engine. It is the major problems for use of biodiesel blends in unmodified or in-use engine. The motivation of the study is to enhance performance and emission characteristics of a diesel engine for use of biodiesel by modifying fuel quality. The studies were carried out in a single cylinder, constant speed diesel engine with rated power of 7.4 kW. The percentage of karanja biodiesel in diesel was kept as constant (B20) throughout the study where as percentage of Diethyl Ether (DEE) was varied from 5% and 10% (by volume) in the biodiesel blend. The smoke opacity (%) decreased significantly for all loads.

5 belt wind tunnels are the most common facility to conduct the experimental aerodynamics development for production cars. Among aerodynamic properties, usually drag is the most important development target, but lift force and its front/rear balance is also important for vehicle dynamics. Related to the lift measurement, it is known that the “pad correction”, the correction in the lift measurement values for the undesirable aerodynamic force acting on wheel belt surface around the tire contact patch, must be accounted. Due to the pad correction measurement difficulties, it is common to simply subtract a fixed amount of lift values from measured lift force. However, this method is obviously not perfect as the pad corrections are different for differing vehicle body shapes, aerodynamic configurations, tire sizes and shapes.

The purpose of this paper is to present the past and present concepts of mechanical test optimization, which means the adjustment of a test machine command signal to achieve desired amplitude and mean levels. In particular, the methods of null pacing, dynamic frequency control, classical amplitude control, and maximum velocity limiting / control are discussed along with their respective application areas, advantages and disadvantages. Also, the factors of data verification and over-complication of the test are noted.

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.

New process development of forging component require lot of process knowledge and experience. Even lots of trial-and-error methods need to be used to arrive at optimum process and initial billet dimensions. But with help of reliable computer simulation tools, now it is possible to optimize the complete process and billet dimensions without a single forging trial. This saves lot of time, energy and money. Additionally, simulation gives much more insight about the process and possible forging defects. In this paper, a complete forging process was needed to be designed for a complex component. With the help of computer simulation, the complete conventional forging process and modified forging process were simulated and optimized. Forging defects were removed during optimization of the process. Also billet weight optimization was carried out. Deciding the pre-forming shape of the billet was the main challenge.