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Automotive exterior lighting systems has to meet several regulatory requirements & manufacture specific internal standards to achieve desired performance. These test specifications are usually generic in nature and formulated mainly to validate the standalone product under standard laboratory conditions. Most of the time these specifications are common for entire vehicle portfolio. The rationale of these standards is to define the basic illuminance in the safe braking distance. Thus, however, using the requirements in these standards to evaluate the performance of front lighting systems is only qualitative. Research on working out method for quantitative evaluation of front lighting system is necessary [1] In practice, however, the luminance levels at road surfaces are usually very dynamic; depend largely on the variations in vehicle parameters, ambient weather conditions, road surface uniformities and effects of light intensity & color contrasts on target visibility.

This paper discusses the test setup and methodology required to validate complete lift axle assembly for simulating the real time test track data. The correlation of rig vs track is discussed. The approach for reduction of validation time by eliminating few of the non-damaging tracks/events, its correlation with real life condition is discussed, and details are presented. With increased competition, vehicle development time has reduced drastically in recent past. Bench test procedure using accelerated test cycle discussed in this paper will help to reduce development time and cost. Process briefed in this paper can also be used for similar test specification for other structural parts or complete suspension system of heavy commercial vehicles.

Self-soiling or surface contamination is usual phenomenon observed during rainy season wherein dirt on road are picked by rotating wheel and later released in air as fine particles. These released dirt particles are further carried by airflow around vehicle and as a result stick on vehicle exterior surfaces leading to surface contamination. Surface dirt contamination is one of critical issues that need consideration during early phase of vehicle development as vehicle styling plays a critical role for airflow around vehicle and therefore settling of dirt on vehicle exterior surfaces. Non consideration of such aspects in design can lead to safety issues with likely non-functioning of parking sensors, camera and visibility issues through ORVM, tailgate glass etc. Hence it is important to understand physical as well as digital techniques for assessment of vehicle for surface dirt contamination.

The automotive engineering fraternity is facing tremendous challenges to improve fuel economy and emissions of the internal combustion engine. The stringent CAFÉ standards for CO2 emissions are expected to become further demanding as time progresses. Indian OEM engineering experts have been considering various technology options to improve vehicle fuel economy. However, the time and costs associated with the development of these strategies and technologies remains a point of major concern and challenge. The potential of a technology to reduce fuel consumption can be estimated in three basic ways. One approach involves developing an actual prototype engine and vehicle with the technologies under evaluation, performing the actual measurements. Some variability from test to test is although expected, this method is the most accurate but time consuming and very expensive.

Nowadays, E- commerce and logistics business model is booming in India with road transport as a major mode of delivery system using containers. As competition in such business are on rise, different ways of improving profit margins are being continuously evolved. One such scenario is to look at reducing transportation cost while reducing fuel consumption. Traditionally, aero dynamics of commercial vehicles have never been in focus during their product development although literature shows major part of total fuel energy is consumed in overcoming aerodynamic drag at and above 60 kmph in case of large commercial vehicle. Hence improving vehicle exterior aerodynamic performance gives opportunity to reduce fuel consumption and thereby business profitability. Also byproduct of this improvement is reduced emissions and meeting regulatory requirements.

Polymers are substituting traditional materials, such as metals, in existing as well as new applications, both for structural and aesthetic applications as they are lightweight, customizable and are easy to mould into complex shapes. With such an extensive use of polymers, there is a need to carefully scrutinize their performance to ensure reliability. This is particularly the case in the automotive and electronic industries where the aesthetic appeal of their products is of prime concern and any visible scratch damage is undesirable. Concern for aesthetics has led to a need for the quantification of visibility due to scratch damage on polymeric surfaces Many painted plastic parts used in vehicles are being replaced with the molded-in color plastics for cost reduction and also due to environmental concerns associated with solvent emissions. There are multiple methods used for scratch evaluation of polymers and paints.

This paper highlights the transition of multi-axis suspension test rig from fixed reacted type to semi-inertial type and the benefits derived thereof in simulation accuracies. The critical influence of ‘Mx’ and ‘Mz’ controls on simulation accuracies has been highlighted. The vital role of ‘Mz’ control in the resonance of wheel pan along ‘Z’ axis and thereof arresting unwanted failures modes in spindle has been duly emphasized. Finally, the role of constraints and boundary conditions on simulation accuracies has been demonstrated by replacing the reaction frame with vehicle body.

The small commercial vehicle business is driven by demand in logistic, last mile transportation and white goods market. And to cater these businesses operational and safety needs, they require closed container on vehicle. As of now, very few OEM’s provide regulatory certified container vehicle because of constrains to meet inertia class of the vehicle. This paper focuses on design of a durable and extremely reliable container, made of the low-cost economy class glass fibre & core material. The present work provides the means to design the composite container for the N1 category of the vehicle. The weight of after-market metal container ranges between 300-350 Kg for this category of vehicle, which affects the overall fuel economy and emission of the vehicle. A detailed CAE analysis is done to design composite container suitable to meet inertia class targets and to achieve weight reduction of 30-40% as compared to metal container.

Corrosion testing and simulation has played a critical role in the development of corrosion resistant automobiles. Much has been learned over a period of time with respect to the automotive corrosion protection and its assessment. A range of coatings and platings are being used in the automotive sector. In this field of application, designs are very complex and focus is on enhanced vehicle level corrosion protection, given the high corrosion warranty costs. The objective of the present study was to develop a electrochemical test method to rapidly and quantitatively screen the corrosion performance of automotive coating systems. The present study compares electrochemical results obtained using a linear polarization resistance (LPR) to results obtained via the standard ASTM B117 salt spray test. Salt spray tests were done on a separate series of these coating systems according to ASTM B117, and the results were ranked from 10 (excellent performance) to 1 (very poor performance).

Oil seal leakage is one of the major failure mode in gearbox / transaxle. Oil seal failures can be due to various reasons like high temperature, insufficient lubrication, failure due to external environment, incorrect fitment etc. Major reason for oil seal failure is insufficient oil flow inside gearbox when vehicle is running on gradient for long duration. When vehicle is running in hilly region, transmission will get incline leading to oil deficiency at one half of the transmission. Oil seal in this location will not get sufficient lubrication and will run dry. Also, there will be rise in local temperature at seal lip to shaft interface leading to failure of oil seal lip. Subsequently, oil leakage from transmission will start from this location when vehicle is running in different terrain. Due to continuous seepage, oil quantity in the transmission will get reduced and may lead to gear failure or seizure of bearing.

Reduction in the drivetrain losses of a vehicle is one of the important contributing factors to amplify the fuel economy of vehicle, particularly in heavy commercial vehicle. The conversion of 6 × 4 drive vehicle into 6 × 2 drive has a benefit of improving the fuel economy of a vehicle by reducing the drivetrain losses occurring in the second rear axle. It was cultured by calculation that in 6 × 2 drive the tractive force available at the wheels, of heavy commercial vehicle with GVW of 44 tons and above, will be much higher than the frictional force transmission capacity of tires, when the engine is producing peak torque on the driving duty cycle like going on steep gradient road. In such situations the tires will start to slip and may result in deteriorating the fuel economy and excessive tire wear. On the other side the flat road driving duty cycle in 6 × 2 drive will give better fuel economy than 6 × 4 drive.

The automotive sector is going through a phase of stiff competition among various Original Equipment Manufacturers for increasing their profitability while ensuring highest levels of customer satisfaction. The biggest challenge for such companies lies in minimizing their overall cost involving investments in Research and Development, manufacturing, after sales service and warranty costs. Higher warranty costs not only affect the net profit but in turn it also affects the brand image of the company to a large extent in the long run. An effort is made here to target such warranty costs due to frequent tail pinion and hub seal leakages on single reduction/hub reduction axles of Heavy Commercial Vehicles in the field. A preliminary study involving the severity analysis of such failures is followed by a step by step investigation of these failures.

Traditionally the bushes used for automotive suspension are tested by methods which either don't address the environmental conditions including dust or mud, which convert a 2-body wear condition to 3-body wear condition prevailing in the field or not representative of the complete load bearing area of the bushes coming in contact with the pin. To address the above issues, a novel method of testing has been designed to take care of the loading type, environmental conditions and load bearing area of the bushes to simulate the field conditions.

A 4t off-road military application vehicle was offered to the customers for assessment. During the evaluation adverse feedback of 1) harsh ride in off-road terrain, particularly during hump-crossing and 2) issues during high mobility were reported. Vehicle configuration was front and rear rigid axle suspension with leaf spring anti-roll bar, 4×4 and all terrain tyres. Vehicle application was “on-road” [GS (General-services)], as well as “off-road” (Reconnaissance purpose). The feedback was critically analyzed on the vehicle with the simulation of field conditions. Since the vehicle was still under customer evaluation, solution for the feedback required was quick and within boundary condition (maximum possible allowable limits of modification) of no major change in the suspension design as it was affects homologation cycle. Present paper describes the detailed analysis of the influence of each parameter on system.

Globalization has intensively driven focus of car manufacturers on comfort and ergonomics. Luxuries are becoming essential features of product mix. Customer’s expectations and desires are changing because of cut throat competition and increasing variety of options. In order to sustain in marketplace, OEM has to be competitive while providing features and options with appropriate quality. Vigorously changing dimensions and definitions of comfort level, luxury and aesthetics has driven the intense focus of OEM’s on customer touch points, customer touch points are those components of vehicle which customer accesses while driving the vehicle and they play vital role in generating drive feel of vehicle. Customer’s drive feel about the vehicle is most complex and critical factor and is of subjective nature. Now days drive feel is an important aspect of product differentiation. Gear shift feel is very crucial touch point in overall drive feel of vehicle.

In today’s automobile market, most OEMs use manual transmission for cars. Gear Shifting is a crucial customer touch point. Any issue or inconvenience caused while shifting gears can result into customer dissatisfaction and will affect the brand image. Synchronizer is a vital subsystem for precise gear shifting mechanism. Based on vehicle application selection of synchronizer for given inertia and speed difference is a key factor which decides overall shift quality of gearbox. For more demanding driver abuse conditions like skip shifting, conventional brass synchronizers have proved inadequate for required speed difference and gear inertia, which eventually results into synchronizer crashing and affects driving performance. To increase synchronizer performance of multi-cone compact brass synchronizer, a ‘Grit blasting process’ has been added. These components tested with an accelerated test plan successfully.

Small goods carrier and passenger vehicles powered by Naturally Aspirated (NA) Direct Injection (DI) diesel engines are popular in Indian automobile market. However, they suffer from inherently high radiated noise and poorly perceived sound quality. This paper documents the steps taken to reduce the radiated noise level from such an engine through structural modifications of major noise radiating components identified in the sound power analysis. The work is summarized as follows; Baseline radiated noise measurements of power train and identification of major noise sources through sound intensity mapping and noise source ranking (NSR) in an Engine Noise Test Cell (ENTC) Design modifications for identified major sources in engine structure Vehicle level assessment of the radiated noise in a Vehicle Semi-Anechoic Chamber (VSAC) for all the design modifications. A reduction of 7 dB at hot idle and 4 - 8 dB in loaded speed sweep conditions was observed with the recommended modifications.

The vehicle pull (sideways) is a complex outcome of many parameters in an automobile vehicle. This is mainly due to steering, suspension, brake, wheels and chassis parameters. The road conditions like road camber also plays an important role in vehicle pull behavior. All efforts are put in design and manufacturing processes to maintain controlled vehicle pull in normal driving condition. Even though normal vehicle pull seems to be in acceptance limit (subjectively), its intensity increases many folds at the time of harsh braking. In these kind of panic situations where driver firmly holds on the steering wheel, it is expected that the vehicle should stop without deviating too much sideways from its intended straight line path to avoid any kinds of accidents. This work is an outcome of systematic study carried out to understand the root cause of brake pull as a field complaint on current production vehicles and adopting best possible solutions to minimize the brake pull.

Tire plays an important role in frontal impacts as it acts as a load path to transfer loads from barrier to side sill or rocker panels of passenger vehicles. In order to achieve better correlation and more reliable predictions of vehicle crash performance in CAE simulations, modeling techniques are continuously getting refined with detailed representation of vehicle components in full vehicle crash simulations. In this study, detailed tire modeling process is explored to represent tire dynamic stiffness more accurately in frontal impact crash simulations. Detailed representation of tire internal components such as steel belts, body plies, steel beads along with rubber tread and sidewall portion have been done. Passenger car tubeless radial tire was chosen for this study. Initially, quasi-static tensile coupon tests were carried out in both longitudinal and lateral direction of tread portion of tire.

Vehicle NVH is one of the critical performance quality parameter and it consists of vibration levels at tactile points and noise levels at ear locations for different vehicle running conditions. There are many sources of noise and vibration in a vehicle, and powertrain is one of the main source. Therefore, it is important to understand and resolve powertrain induced noise and vibration issues at early design stage with efficient simulation techniques. The work presented here deals with the use of systematic CAE approach for prediction and resolution of structure borne in-cab noise due to powertrain excitations. During NVH testing of SUV vehicle, boom noise is observed at low frequency. Detailed full vehicle level simulation model consisting of vibro-acoustic trimmed BIW, front and rear suspension, and driveline with powertrain modal model is built.