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Globally, automotive sector is moving towards improving off-road performance, durability and safety. Need of off-road performance leads to unpredictable overload to powertrain system due to unpaved roads and abuse driving conditions. Generally, shafts and gears in the transmission system are designed to meet infinite life. But, under abuse condition, it undergo overloads in both torsional and bending modes and finally, weak part in the entire system tend to fail first. This paper represents the failure analysis of one such an incident happened in output shaft under abuse test condition. Failure mode was confirmed as torsional overload using Stereo microscope and SEM. Application stress and shear strength of the shaft was calculated and found overstressing was the cause of failure. To avoid recurrence of breakage, improvement options were identified and subjected to static torsional test to quantify the improvement level.

The cabin cool down performance is influenced by heat load, AC system components and Air handling components. The air handling components are AC duct, vane and vent. Design of AC duct vane plays a crucial role in the airflow directivity in cabin which enhances the cabin cool down performance. Simulations are carried out by rotating the vanes manually and requires post process for every iteration. It leads to more time consuming and more number of simulations to achieve the target value. Research articles focusing on automation and optimization of vane articulation studies are scanty. Thus, the objective of this work is to execute the vane articulation study with less manual intervention. A parametric approach is developed by integrating ANSA and ANSYS FLUENT tools. With Direct Fit Morphing and DoE study approach from ANSA delivers the surface mesh model for the different vane angle configurations.

Vehicles with manual transmission are still the most preferred choice in emerging markets like India due to their benefits in cost, simplicity and fuel economy. However, the ever-increasing vehicle population and traffic congestion demand a smooth clutch operation and a comfortable launch behaviour of any manual transmission vehicle. In the present work, the launch performance of a sports-utility vehicle (SUV) equipped with dual mass flywheel (DMF) and self-adjusting technology (SAT) clutch could be improved significantly by optimizing the clutch system. The vehicle was observed to be having a mild judder during clutch release (with 0% accelerator pedal input) in a normal 1st gear launch in flat road conditions. An extensive experimental measurement at the vehicle level could reveal the launch judder is mainly due to the 1st order excitation forces created by the geometrical inaccuracy of the internal parts of the clutch system.

The present work is focussed on the real-world challenges of a dual mass flywheel (DMF) equipped vehicle in the Indian market. DMFs are widely used to isolate the drivetrain from the high torsional vibrations induced by the engine. While DMFs can significantly improve noise, vibration and harshness (NVH) characteristics of a vehicle, there are multiple challenges experienced in real-world operating conditions when compared with the single mass flywheel (SMF). The present work explains the challenges of using a DMF in a high power-density diesel powertrain for a multi-purpose vehicle (MPV) application in the Indian market. Measurements on the flat-road operating conditions revealed that the DMF vehicle is very sensitive for launch behaviour and requires a higher clutch modulation. Vibration measurements at the driver’s seat confirm that the SMF vehicle could be launched more comfortably at the engine idle speed of 850 RPM.

Across the automotive industries, objective measurements and subjective assessment of vehicle ride performance are routinely carried out during development as well as validation phase. Objective measurements are receiving increased attention as they are generally believed to offer a higher degree of objectivity and repeatability compared to the subjective assessment alone. Typical industry practices include the acquisition of vehicle-occupant vibrational response on specified road sections, test surfaces on proving grounds or in a controlled input environment such as four-poster test rig. In presented work, a study is performed on the repeatability of vehicle ride performance metrics such as weighted RMS acceleration and frequency responses using the data acquired in repeated trials conducted using three different sports utility vehicles (SUVs) on a sufficiently long designated road section.

Aeroacoustics of vehicles is becoming an important design criterion as it directly affects passenger’s comfort. The wind noise at highway speeds (>80 KMPH) is a critical quality concern under normal and crosswind conditions and dominant factor in assessing acoustic comfort of the vehicle. Wind noise is caused by the vortex air flow around a vehicle body and air leakage through the sealing gaps of attached parts. This majorly contributes to high frequency noise (>250 Hz). Accurate identification and control of noise sources and leakage paths result in improved acoustic comfort of the vehicle. In this paper, aero-acoustic quality characteristics of validation prototype vehicle are studied. The major wind noise sources and leakage paths in the vehicle are identified through in-house blower set up in the semi anechoic room. The overall wind noise level and articulation index of vehicle at various speeds are determined through on- road measurements.

Indian Automobile Industry has started using Six Sigma for Vehicle Design and process improvement to compete with Global competition. This Paper describes how the Tools of Six Sigma shall be used as an Effective Tool for both redefining the Design and the Process Improvement. This Paper talks on the evolution of DMADV approach in Indian Automobile Industry compared to the related Trends in Other Manufacturing Sectors. The Author describes how the warranty failures in Commercial Segment Vehicle Category which was the selling talk for the Competition was addressed in Leading Indian Automobile OEM. As this Failure was adversely impacting customer satisfaction and no solution seemed forthcoming, top Management indicated to use a radically different approach to solve the problem within a years’ time.

Increasing complexity in E/E architecture poses several challenges in developing comfortable, clean and safe cars. This mandates robust processes to mitigate potential hazards due to malfunction of electronic systems throughout the product life cycle. With the advent of ISO 26262 [1] which provides guidelines for developing safe cars, the process is getting standardized towards safer mobility. In this paper, the functional safety process is briefly covered and a case study of Hazard Analysis and Risk Assessment for specific E/E system is presented. An in-house tool developed for functional safety process and management is covered.

The emerging business imperative of frequent new product introduction in market throws up challenge to shorten testing and evaluation time. Advanced test facilities and statistical tools have a greater role in reducing the evaluation cycle time. Considering limitations of field testing, a need was felt to simulate field condition in the laboratory i.e., ‘Bringing field to lab’. In this paper, an effort is made to explain the concept of ‘Bringing field to lab’ and the approach towards accomplishing it. The methodology developed for assessing effectiveness of laboratory tests i.e., ‘Power of Lab’ is shared. Various means of accelerating the tests and verifying field to lab correlation are explained. In quest to pursue the vision of ‘Bringing field to lab’ program, a new test facility has been developed to evaluate tractor i.e., Three-Poster Test System. Features of this test system, along with it’s role in ‘Bringing field to lab’, are shared along with the test results obtained.