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This paper describes the procedure of root cause analysis and evaluation of the life of a component that is prone to fatigue failures. The durability testing of components subjected to continuous vibrations in their operating conditions tend to fail after long period of exposure. This makes it difficult and time consuming to test and analyse them in the actual operating conditions. This paper establishes a method of accelerated durability testing for failure modes and life cycle based on the results of Frequency Response Function and modal analysis. This helped in reducing the product development / improvement time.

One of the primary concern during assessment of structural integrity of vehicle bodies is the quality of joints used therein. The increased trend in vehicle weight reduction (through use of thin sheet panels) calls for more critical evaluation of the quality of such joints. The electric Resistance Spot Welding (RSW) is one of the largely used joining process for vehicle body structure. Besides the quality of sheet metal, the quality of RSW joints is largely governed by the process parameters e.g. weld current, hold time, squeeze time etc. The quality of RSW joints for durability can be assessed by mechanical strength and fatigue life. The paper presents a methodology for durability assessment of such joints using laboratory specimens and arriving at optimum values of process parameters to maximise the fatigue life. The methodology presented makes extensive use of Design of Experiment (DOE) techniques for better reliability of the results.

In the absence of Anthropometric and Ergonomic data on Indian Driving population, a project entitled “Ergonomic study on Indian driving population” was under taken by The Automotive Research Association of India, Pune with assistance of the Government of India and the Indian Automotive industries. The objective was to survey and compile anthrpometric data in standing, sitting and preferred driving position for 4-wheeler and 2-wheeler driving positions to assist the automobile manufacturers in India to cater their design to Indian population and make an Indian driver comfortable. This paper briefly presents the methodology adopted for the survey along with the results. Also studies were conducted on finger pressure, hand pressure and foot pressure exerted by the driver, which would serve as the baseline data for designing controls for the vehicle. A comparison with a typical American data has revealed many correlation and differences.

The paper contains experimental results related to the driver's visibility and polarized headlighting system. The interpretation of visibility is done in terms of contrast in almost every situation. Results showing the variation of high and low beam intensity as a function of lateral displacement between the vehicles are presented. Parameters like headlamp mounting height and height of driver's eye point (DEP) have also been considered. A comparative study between polarized and conventional headlighting systems is performed under different situations. The performance metrics chosen for this purpose are visibility and glare.

Strain controlled tests were performed on 35 C8 steel specimens (IS 3930-1979) to determine cyclic stress-strain curve (CSSC) by Companion Specimens Test (CST), Multiple Step Test (MST) and Incremental Step Test (IST) procedures. A good agreement was found between the CSSCs obtained by CST and MST procedures. The CSSCs obtained by IST procedure using Incremental Step Loading Blocks (ISLB) of different maximum strain amplitude indicate that the parameters of CSSC depend on the maximum strain amplitude in the ISLB and resulted in a family of CSSCs. The dependence of CSSC parameters on the maximum strain amplitude in the ISLB are approximated by polynomials. Fatigue lives estimated based on IST results for irregular strain-time histories were found to be comparable with the experimentally evaluated fatigue lives.

With ever-increasing concern for the occupant safety, it is desirable that the design of truck cab should meet the safety requirements specified in ECE R-29. The cab must be designed in such a way that, sufficient survival space to be guaranteed in the event of accident for the safety of the driver and co-driver. It was found that there are some areas, which are not covered by the standard or the standard is not very clear. This paper discusses about the practical problems incurred during implementation of the standard in Indian scenario and also suggests possible practical solutions.

In India, three wheelers are the major mode of the public transport used by common people. The competition in the market necessitates to develop a vehicle for maximum customer satisfaction. One of the important attribute of vehicle is passenger ride comfort. In the past, majority of the work on the ride comfort study has been carried out on passenger vehicles, which are mostly owner driven, but no detailed study has been carried out on quantification of driver as well as passenger ride comfort for a three-wheeler. In the present exercise, major emphasis has been given to ride comfort of the passenger and to characterize them with different makes of three wheelers. There are number of algorithms available to quantitatively measure the performance of ride comfort. The most popular one is ISO 2631. These standards are primarily developed based on response of human organs to different frequency range.

With increasing competition and number of global players entering the Indian market, the Indian tractor scenario is as hot and fluid as that of the passenger car. Tractor manufacturers are under tremendous market pressure to become internationally competitive and bring out new tractor models in the shortest time possible as well as keeping the validation costs to a minimum. This is making them to look for advanced techniques for reducing the development time such as service load data acquisition and analysis, life prediction and accelerated simulation tests for design validation. This paper presents such an effort by an Indian tractor manufacturer along with ARAL Design validation of the chassis was carried out as a complete structure instead of carrying out on individual components.