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Automotive floor carpet serves the purpose of insulating airborne noises like road-tire noise, transmission noise, fuel pump noise etc. Most commonly used automotive floor carpet structure is- molded sound barrier (PE, vinyl etc.) decoupled from the floor pan with an absorber such as felt. With increasing customer expectations and fuel efficiency requirements, the NVH requirements are increasing as well. The only possible way of increasing acoustic performance (Specifically, Sound Transmission Loss, STL) in the mentioned carpet structure is to increase the barrier material. This solution, however, comes at a great weight penalty. Theoretically, increasing the number of decoupled barrier layers greatly enhances the STL performance of an acoustic packaging for same weight. In practice, however, this solution presents problems like- ineffectiveness at lower frequencies, sudden dip in performance at modal frequencies.

The most widely used type of windshield wiper system employs a coil spring for wiper arm pressure generation. This spring is fixed between the arm head (fixed part) and wiper arm (moving part) and the tension in the spring is responsible for pressure generation. The present arrangement although being unsophisticated design, has following drawbacks: Inability to change wiper arm pressure according to change in vehicle speed. Inability to provide constant arm pressure during the complete range of motion along varying curvature of windshield. Inability to reduce/remove the continuous pressure on wiper blade when vehicle is parked for long durations resulting in permanent deformation of wiper blade rubber. This paper describes how electromagnets can be used to overcome the above stated inherent limitations of the windshield wiper system. An electromagnet is a device which produces magnetic field on application of electric current.

The biggest challenge in vehicle BIW design today is to make a light, cost effective and energy absorbing structure. With the increasing competition as well as increasing customer awareness, today’s vehicle has to satisfy several aesthetic and functional requirements besides the mandatory regulatory requirements. Working on global platform is challenging in order to comply with both pedestrian protection and low speed bumper impact (ECE-R42) and, at the same time, to meet the styling intent of reducing the front overhang. Pedestrian lower leg compliance demands space between bumper member and bumper: a condition that reduces the space available for energy absorption during low speed impact (ECE-R42). Therefore, reduction in front overhang poses a problem in meeting both the requirements with limited space. This paper outlines vehicle case study in order to optimize the design of Bumper Beam structure, for complying with regulatory requirements while satisfying the styling intent.

Vehicle Hood being the face of a passenger car poses the challenge to meet the regulatory and aesthetic requirements. Urge to make a saleable product makes aesthetics a primary condition. This eventually makes the role of structure optimization much more important. Pedestrian protection- a recent development in the Indian automotive industry, known for dynamics of cost competitive cars, has posed the challenge to make passenger cars meeting the regulation at minimal cost. The paper demonstrates structure optimization of hood and design of peripheral parts for meeting pedestrian protection performance keeping the focus on low cost of ownership. The paper discusses development of an in-house methodology for meeting Headform compliance of a flagship model of Maruti Suzuki India Ltd., providing detailed analysis of the procedure followed from introduction stage of regulatory requirement in the project to final validation of the engineering intent.

With the increasing competition in the automotive industry, customer experience & satisfaction is at the top of every organization's goals. The customers have evolved & NVH refinement has become the parameter for their decision making in buying a car. The major source of rumble noise in a vehicle is the induced vibrations due to combustion forces in an IC engine. These vibrations are then transferred to the vehicle body through engine mounts. Hence engine mounts play a key role in defining the NVH & the ride performance of any vehicle. However, it is infeasible to validate every mount design through the physical test as it will be both costly & time-consuming. But multiple design iterations can be verified by the CAE approach quite effectively. This paper focuses on the novel CAE approach to evaluate the mount vibrations due to engine dynamics. The process involves preparing a FEA model of the complete Powertrain system.

Valve train system is one major contributor to engine overall friction loss and is approximately 30% of total engine friction at lower speed and approximately 20 % at higher engine speed. Valve spring loads (preload and working) are proportional to friction loss of valve train. To optimizing the valve spring design main requirement is valve train perform it function safely at maximum engine cutoff RPM with minimum preload and working load. Robustness and frictional power loss are contradicting requirement, robustness demand high stiffness spring for better valve jump and bounce performance with dynamic safe valve spring design, on the other hand low frictional power loss demand for use of low stiffness spring. To optimize the valve spring stiffness for meeting both the requirement we need accurate prediction of valve spring in design stage and good correlation with testing data to reduce the number of iterations.

Radiators are one of the major components in the automotive engine cooling system. The road excitations from the frame to the radiator are dampened using rubber bushes. In this work, we analyzed a radiator sub-assembly with bushes by applying acceleration which are recorded at the center of gravity of the radiator. The radiator is considered as the concentrated mass which is attached to the upper and the lower radiator tank which is further connected to the frame through the bushings. An implicit transient dynamic analysis is set up. The hyper elastic coefficients for EPDM rubber are determined using the experimental data fit and structural damping coefficients are applied. When excited by the acceleration applied at center of the radiator component, the rubber bushes are deformed severely. Moreover, the analysis shows high strains in certain location on the upper bush where the part showed actual failure in the testing.

The interface between human body and automotive seat contours is seat upholstery. Seating comfort has a functional correlation to the upholstery. Two seats having different upholstery will give different comfort perception. Even an ergonomically designed seat if fitted with poor quality fabric will subdue the seat comfort drastically. The effect of fabric comfort ranges from initial short term to long term comfort, driven by properties like wick-ability and factors like thermal stress. Beyond material characteristics, fabric fit also plays an important role. This paper analyses the effect of fabric parameters and construction on automotive seat comfort. A comprehensive comparative study is followed by systematic analysis and comfort improvement scope through upholstery. The research is to conclude potential of the seat fabric in enhancing the automotive seating comfort within stipulated constraints of fabric properties and cost.

Due to intense peak summer temperatures and sunny summers in tropical countries like India etc., achieving the required thermal comfort of car occupants without compromising on fuel efficiency is becoming increasingly challenging. The major source of heat load on vehicle is Solar Load. Therefore, a study has been conducted to evaluate the heat load on vehicle cabin due to solar radiations and its impact on vehicle air-conditioning system performance with various combinations of door glasses and windscreen. The glasses used for this study are classified as green, dark green, dark gray, standard PVB (Polyvinyl Butyral) windscreen and PVB windscreen having infrared cut particles. For each glass, part level evaluation was done to find out the percentage transmittance of light of different wavelengths and heat flux through each glass.

Fabrics play a vital role in defining the overall aesthetics of automotive interiors, primarily with fabric cleanliness. In this respect, the cleanliness of the fabric also becomes equally important. The fabric interior in a car is very prone to staining due to the spilling of water or any liquid substance over it. In order to protect and enhance the life of the fabric, various chemical treatments are suggested as fabric finishes. There are different chemical bases available for the same. Fluorocarbon base is the most effective treatment and is the focus of this study. This chemical treatment lowers the surface energy of the fabric by increasing the hydrophobicity of fabric. Hence, the liquid roll over the surface in the form of droplets by creating higher contact angle over the fiber surface. This study focuses on the effect of chemical treatment on the automotive fabric’s parameters, especially light color fabric.

Automobile components are usually subjected to complex varying loads. Thus, fatigue failure is a common mode of failure in automobile components. Accurately predicting the fatigue life is the key point for light weight and also reliability design of automobile components. Various life prediction theories are being used in the automotive industry for damage analysis using material S-N curves. However, due to variability in manufacturing, material spec etc. it is difficult to predict the experimental lives using conventional theories. Probability based statistical modeling is prevalent in the industry for life prediction. Probabilistic plots of cycles to failure to constant amplitude loads are plotted and used for prediction purpose. As the component is subjected to varying loads in real world, defining a single parameter i.e. damage would be more relevant compared to loads.

India is a country of diversity. From North to South, east to west, one can find altogether different culture, religions, spoken languages, foods, weather conditions, people lifestyles, dressing styles etc. This vast diversity of India poses a great challenge in front of Indian Automobile Manufacturers, so as to assimilate all the requirements (of this big nation) in one single car (design). For example, many people in India wear turban (out of their religious beliefs or cultural heritage). So, is it required to keep enough consideration for Turban wearing population in vehicle design? Turban, unlike caps or hats, is something which is tied on the head (not just only kept). It is something which cannot be removed whenever required. So, it can somehow be considered as an integral part of body (as an added head dimension). So, it becomes all the more important to thoroughly understand this aspect & keep a consideration for the same in vehicle design.

A typical wheel development process involves designing a wheel based on a defined set of criteria and parameters followed by verification on CAE. The virtual testing is followed by bench level and vehicle level testing post which the design is finalized for the wheel. This paper aims to establish the learning which was accomplished for one such development process. The entire wheel development process had to be analyzed from scratch to arrive at a countermeasure for the problem. This paper will not only establish the detailed analysis employed to determine the countermeasure but also highlight its significance for the future development proposals. The paper first establishes the failure which is followed by the detailed analysis to determine the type of failure, impact levels and the basic underlying conditions. This leads to a systematic approach of verification which encompasses the manufacturing process as well as the test methodology.

Vehicles in India will soon come with star ratings, signifying how environment-friendly they are. The OEM's have braced to improve fuel economy of their existing & upcoming models. Tyre rolling resistance is one of the significant factors for vehicle fuel consumption. Improvement in Fuel consumption is always a prime focus area & to improve it all major factors are considered. In newly launched models, the low rolling resistance tyre development was initiated. The project is challenging as it requires not only achieving low rolling resistance in smaller size tyres (12″ to 13″) but also required to meet other critical vehicle performance parameters like ride, handling, NVH & durability. Effects of Tyre construction, rubber compound were analyzed to achieve lower rolling resistance and better durability of tyre. In addition, the factors affecting the rolling resistance of tyre like inflation pressure, load, and speed in smaller tyre sizes (12″ to 13″) are discussed in this paper.

Global automobile market is very sensitive to vehicle fuel economy. Gross vehicle weight has substantial effects on FE. Hence, for designers it becomes utmost important to work on the weight reduction ideas up to single component level. Fuel delivery pipe (Fuel Rail) is one such component where there is a big potential. Fuel rail is an integral part of the vehicle fuel system and is mounted on the engine. Primarily it serves as a channel of fuel supply from fuel tank through fuel lines to the multiple fuel injectors, which further sprays the fuel into intake ports at high pressure. Due to opening and closing of injectors, pulsations are generated in fuel lines, so fuel rail also acts as a surge tank as well as a pulsation damper. All these factors make the design of a fuel rail very critical and unique for a particular engine. Materials like aluminum, plastic and sheet metal are generally used for fuel rail manufacturing.

Hardened steel is the majorly used raw material for automotive components. In spite of its abundance, its application is limited due to low fatigue life in dynamic loading. Shot peening is one of the identified processes to improve the fatigue life of the ductile steel by inducing the work hardening & surface improvement. The process of shot peening involves the bombardment of shots on the component surface. As the process & technique, the shot size selection plays very important role in the fatigue life improvement as it alters the results substantially. Also during the process, shot size decreases due to the normal wear of the shots after hitting the component surface. As a result, there is always a ratio of various sizes of the shots involved in the process. Therefore it becomes imperative to control the shot size ratio for obtaining the required work hardening & possible fatigue life improvement.

Interior sound quality is one of the significant factors contributing to the comfort level of the occupants of a passenger car. One of the major reasons for the deterioration of interior sound quality is the booming noise. Booming noise is a low frequency (20Hz∼300Hz) structure borne noise which occurs mainly due to the powertrain excitations or road excitations. Several methods have been developed over time to identify and troubleshoot the causes of booming noise [1]. In this paper an attempt has been made to understand the booming noise by analyzing structural (panels) and acoustic (cavity) modes. Both the structural modes and the acoustic modes of the vehicle cabin were measured experimentally on a B-segment hatchback vehicle using a novel approach and the coupled modes were identified.

To cater the push towards “Vehicle Light Weighting”, both sprung and unsprung mass are being reduced. This results in reduced stiffness and thus has a profound undesirable effect on the overall vehicle handling. To understand the effect of different reduction ratios of sprung to unsprung mass; it is desired to understand how changes in stiffness affect the overall vehicle handling characteristics. Therefore, the study was conducted to experiment with different values of roll stiffness, at both front and rear axles and comparing the frequency response and phase change of Yaw Gain observed through a Pulse Input test. The present work is further correlated with subjective feedback to predict the shift in vehicle balance and handling characteristics.

Electrostatic charge generation in fabric is a common phenomenon. This phenomenon of charge generation & transfer of the same to human body is more in case of fabrics made of polyester yarns due to interface property of the material. The charge generation may result in attraction of dust on the fabric surface, clinginess & may also result in uncomfortable shock to the human body. This situation is attributed to various parameters such as fabric construction, yarn properties, yarn finish & various coating on the yarn. Since, polyester fabric is prime material used in seating; there have been many incidences of rubbing of seat fabric to human body, resulting in generation of static charge. This study focuses on understanding the effect of various fabric parameters on electrostatic charge generation. The study will also look into various potential solutions to reduce the charge generation with their merits and demerits.

The biggest challenge in vehicle BIW design today is to make a light, cost effective and energy absorbing structure. With the increasing competition as well as increasing customer awareness, today’s vehicle has to satisfy several aesthetic and functional requirements besides the mandatory regulatory requirements. While working on global platform, it is challenging to comply with both pedestrian protection and low speed bumper impact (ECE-R42) and at the same time meeting the styling intent of reducing the front overhang. Pedestrian lower leg compliance demands space between bumper member and bumper, a condition that reduces the space available for energy absorption during low speed impact (ECE-R42). Therefore, reduction in front overhang poses a problem in meeting both the requirements with limited space. This paper outlines vehicle case study in order to optimize the design of Bumper Beam structure, for complying with regulatory requirements while satisfying the styling intent.