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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.

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.

As a part of the Safety Test Facility Building initiated by ARAI, the bungee sled facility has been designed, setup and proven to meet the National and International Regulatory Requirements. The facility is being extensively used for Type Approval tests of safety belts, seats and their anchorages. The paper describes the capabilities of the facility, shares the first hand experience of the conflicting design considerations, infrastructure viz., civil structure, lighting, data acquisition, high speed videography and motion analysis software.