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Variety of metals and elastomers/plastics are used in vehicle fuel systems. Though higher ethanol in gasoline can lead to efficient burning of fuel, material compatibility of non-metals is one of the major issues of concern. Material compatibility issue needs to be addressed before using higher contents of ethanol in gasoline because of reasons like permeation, swelling, leaching and plasticization, which lead to loss of material properties and subsequently resulting into field failures. For assessment of whether the fuel system will be able to perform as intended for its complete design life, it is necessary to know the impact of use of modified fuel on fuel system components. The impact on the in-use vehicles is particularly important in Indian context, where vehicles even more than 10 years old are plying. Most of the vehicles have not been designed for the 10% ethanol gasoline blend except for a few 4-wheelers.

Damper is one of the important parts of switchgear, which smoothens the impact during opening and closing operation. The energy levels and the forces for Extra High Voltage (EHV) range of product is upto 5 kJ. To reduce the development cycle time, calibration of simulation with respect to actual result is a necessity. Crompton Greaves Ltd (CGL) has done joint effort with ARAI for the calibration of three different designs of damper. The suitably instrumented rod end of hydraulic damper was characterized for maximum axial load of +/−60 kN using servo hydraulic actuator in lab. Load vs strain data was acquired and graphs were plotted. The same instrumented rod end was fitted on three different Hydraulic Dampers and the loads acting during ‘Circuit Opening’ and ‘Circuit Closing’ operations were calculated using acquired strain data and the factors obtained from characterization of rod. For two dampers, the predicted results are within 15% with respect to actual.

A comprehensive exercise for generation of wheel load database and spectrum of different categories of vehicles was carried out. The vehicles have been chosen so as to represent the best possible variation of vehicles all over the country. Dedicated Wheel Force Transducers (WFT) for all corners of all test vehicles have been utilized along with a host of traditional transducers at identified locations of the test vehicles. An exhaustive survey and data acquisition exercise has also been carried out in different geographical regions of India in order to determine the various attributes related to various types of vehicles, type of usage, driving patterns etc. Instrumented test vehicles have been run on identified routes and regions as deciphered from the survey, as well as on proving grounds. Detailed analysis of the test data from different categories vehicles has been carried out to determine the variation of wheel forces, moments and other vehicle durability parameters.

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.

The Indian automotive industry today stands as the most vibrant, modern and upbeat automobile market in the world and is the current focus of venture for almost every leading vehicle manufacturer in the world. New variants launched in Indian market are tested by instrumenting it with different sensors and running it on proving ground and public roads and further validated in the laboratory. These testing practices may be derived from the market needs and driving pattern of that region and trying to adopt for Indian condition. The driving characteristics obtained from other markets may not represent Indian driving patterns. Similarly Indian vehicle manufacturer also need to know updated driving characteristics, which is very much dynamic and changing with new type of roads/driving habit etc. There is a need to tune the vehicle for realistic Indian conditions and driving pattern.

An open wheeled open cockpit racing-car with Maruti 800 BS III MPFI engine was designed and built for the SUPRA SAE INDIA 2011 student competition by ARAI academy students. The car won the best engineering design award and second in CAE category. The key focus was to build a car with superior safety and comfort. This work discusses in detail about the design, analysis and validation of the primary structure of the car which includes chassis and impact attenuator. This paper will serve as a reference to the future students who are participating in supra competition. A review of supra sae rules relating to chassis is used to develop realistic parameters. Based on the weight distribution calculations and the hard points the chassis is designed, modelled using cad tool and simulated for longitudinal acceleration, lateral acceleration, braking condition, braking with one circuit failure, bending stiffness and Torsional stiffness using finite element analysis.

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.

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 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.

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.

Road surface, payload and speed of the vehicle are important parameters, which affect the life of a vehicle. This paper discusses the relationship between road/load/speed and damage to the vehicle as a whole and automotive structure in particular. This will help the designer to understand non-linear relationship between different service conditions and damage and to arrive at realistic input spindle loads for design considerations. This will also help the evaluation engineer in the development of durability cycle by correlating different environmental conditions with actual service conditions.

Accelerated life evaluation of vehicle has become the order of the day with the continuously decreasing development time for product development. With the rapid progress in the computer aided design area, today it is possible to feed-in virtual test tracks so that even before a prototype is made, a life estimate could be arrived at. Further, the advent of rapid prototyping has also resulted in reducing the time required for development of prototypes considerably. This has put the proving engineers under tremendous pressure in reducing the time required for design validation. This has resulted in a number of techniques being developed for reducing number of tests required as well as test duration in validation of the prototypes. One such technique is non-square matrix simulation. This technique can also be used for the investigation of failures and validation of the modifications.

The duration for the development of a new vehicle model is continuously decreasing. This does not permit adequate time for proving component assemblies and vehicles to be evaluated for durability by conventional measures. However, increasing competition and quality consciousness calls for an assured life with a high degree of confidence. This has forced the test engineers to look for techniques for accelerating the durability evaluation. The technique calls for concepts for compressing the evaluation time. This can be achieved by compression in both time as well as frequency domain. Further, it also calls for correct techniques for the mixing of roads, extrapolation of data acquired over a small distance to the vehicle life, evaluation and elimination of non or less damaging inputs, etc. This paper reviews some of the existing techniques and describes case studies of how accelerated testing can be applied in vehicle development.