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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.

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.

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.

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.

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.

Shock loads/Jerk is a major cause of gearbox failure which occurs during abusive driving condition. In passenger car torque spikes are experienced by the transmission during launch/sudden clutch release events on flat road or off-road. Whereas, in case of commercial vehicle torque spikes are generated while operation in mines and off-road application especially in tipper vehicles. Torque spikes experienced by the gearbox can lead to gear failure, gear slippage and structural failure of housing. Research has been done till now to improve the design of gearbox to address such failures. However, with increased focus on transmission downsizing and improved vehicle performance (by weight reduction and more powerful engine) it is necessary to have optimum design to meet transmission life. This paper discuss the test setup and methodology used to simulate the torque spikes on test bench. To develop the test procedure huge data was collected on commercial vehicles.

Corrosion in automotive industry is broadly categorized into cosmetic & perforation corrosion. Cosmetic corrosion comprises of superficial red rust which is deleterious to the overall aesthetic appeal of the vehicle but can be rectified. Perforation corrosion involves complete erosion of the panel, compromising structural integrity of the respective part. Perforation corrosion demands part replacement. In order to tackle this menace, automotive OEMs have formulated varied corrosion strategies in terms of selection of appropriate substrate, part design & surface protection scheme. Validation of various corrosion strategies become pivotal during the development phase of various parts and assemblies. Traditionally, Salt Spray Test (SST) has been used to determine corrosion life of materials/parts/assemblies. This test however does not simulate real-world conditions.

In regions like Indian Subcontinent, Gulf or Saharan & Sub-Saharan Africa, where the sunshine is abundant almost all year round, air-conditioning is an important aspect of vehicles (passenger cars, buses etc.). Higher heat means higher cooling demand which in turn means bigger AC system. Like other auxiliaries, AC compressor is a parasitic load on the engine. The best way to beat heat and reduce cabin heat load is to stop heat build-up itself. The present paper explores one such means of reducing cabin heat build-up by leveraging latent heat properties of phase change materials and thus improving the air condition performance. With the help of a case study this paper aims at detailing comprehensive effect of phase change material (PCM) and its application on the heat build-up inside the cabin of a vehicle, the air conditioning cooling performance, the time required to achieve comfort temperature, work of compression performed by AC compressor and COP.

Frame is one of the vital part of Light & Heavy Commercial vehicle which holds all the parts and testing the frame is not a cost effective as the complete vehicle assembly needs to be tested as the individual testing of frame is not formulated for testing. In the development stage of the vehicle we always seek for a quick, cost effective and reliable methodology so that any modification can be made by identifying the failures. In this paper we have addressed this problem by developing a generic frame test methodology by which the frame can be tested in the preliminary stage of development in a cost effective way and reliable way. The Multi Body Dynamics Simulation was carried out and rig was designed comprising of servo hydraulic actuators. The frame was instrumented to acquire the Field, Event and Torture track data for the formulation and verification of the synthetic drives.

Indian automotive market has grown extremely competitive in the recent past. In order to meet the ever growing expectations of the customers, automobile manufacturers are compelled to offer their products under superior quality with supreme comfort. Customers wish of high levels of tactile comfort in the cabin compartment and effortless operation of peripherals will result in negligible fatigue and a pleasant drive, needs to be duly fulfilled. One has to focus more on Gear shift lever and Steering wheel, which are being the most sensitive tactile points in an automobile. The gear shift lever knob is frequently used and significantly influences the perception of the shift comfort for a driver during actual vehicle application.

In current scenario, there is trend to use stainless steels in place of carbon steels and aluminized carbon steels for Exhaust application. In response to changing regulatory requirements and durability performance requirements of exhaust systems, the ferritic stainless steels are proven to be best suited for the purpose. There are multiple ferritic stainless steels available as options for exhaust system. The material in an exhaust system is subject to heat, oxidation, corrosion and condensate. These environment condition demands that exhaust material should possess high temperature corrosion and oxidation resistance along with required mechanical performance such as vibration and thermo-mechanical load cycles. This work is an attempt to develop simulated test methods for corrosion and thermal environment and evaluate performance of commonly used ferritic stainless steels.

Traditionally, vehicle ride and comfort is evaluated, subjectively as well as objectively. Based on the outcome of subjective and objective tests, it is refined by optimizing primary suspension system, secondary suspension system, seating system, rubber bushings, frame and BIW for mass, stiffness, damping, geometry etc. Many a time subjective assessment results stands in contradiction to the objective assessment results; emphasizing need for having good correlation between subjective and objective test results. In such cases, it is ambiguous to decide suitable design refinement action and can lead to no improvement situation. Hence, it is essential to have concurring test procedures for subjective and objective ride evaluation. This paper describes a novel methodology to address the above said challenge. There are defined set of test events and measurement data points to be used in subjective and objective testing.