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In a typical passenger vehicle, there can be different types of noises generated which are broadly categorized as Interior Noise and Exterior Noise. The interior noise sources can be further classified into noises which can be Structure Borne or Air Borne. One of the major sources of both structure borne and airborne noise generation is the powertrain of the vehicle. The structure-borne noise and vibrations generated from the powertrain is usually transferred to the vehicle body through its attachment points to the body and the powertrain driveline. These induced body vibrations can sometimes cause the acoustic cavity of the passenger cabin to go into resonance which results in an annoying and disturbing noise for the passengers, called Booming Noise. Very often, one or more than one vehicle body panels show a dominant contribution in inducing this acoustic cavity resonance.

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.

Hood is the closure provided in the frontal portion of the vehicle for covering the engine room. Any component disposed in the frontal portion of the vehicle becomes important because of aesthetic as well as regulatory requirements. Introduction of new regulations like pedestrian protection brings new challenges for the original equipment manufacturers and the governing authorities. Introduction of Pedestrian Protection regulation, a recent development in the automotive industry, has thrown several questions in front of original equipment manufacturers. This work explains the procedure to address such question and the learning associated with it.

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.

The fuel efficiency of a vehicle depends on multiple factors such as engine efficiency, type of fuel, aerodynamic drag, and tire friction and vehicle weight. Analysis of weight and functionality was done, to develop a lightweight and low-cost Roof rack rail. The Roof rack rail is made up of a lightweight material with thin cross section and has the design that allows the fitment of luggage carrier or luggage rack on the car roof. In starting this paper describes the design and weight contribution by standard Roof rack rail and its related parts. Secondly, the selection of material within different proposed options studied and a comparison of manufacturing and design-related factors. Thirdly, it has a description of the design of Roof rack rail to accommodate the luggage carrier fitment on the car roof. Moreover, optimizations of Roof rack rail design by continuous change in position, shape, and parts used.

Recently, the Flexible Pedestrian Legform Impactor (or Flex-PLI) - an advancement over the existing EEVC legform - was included in the Global Technical Regulation for Pedestrian Safety viz. GTR-9. The legform tool undergoes impact testing with vehicle at 40kmph in order to evaluate the frontal structure of vehicle for Pedestrian Safety. Being more biofidelic design over the old EEVC legform, Flex-PLI is more flexible and sensitive towards different vehicle designs, shapes and inner bumper structure. This flexibility and sensitiveness of its design also calls for examining the Manufactured FlexPLI for its efficacy under impact testing in terms of its Durability, Repeatability and Reproducibility. This study aims at validating the performance of the test device by building a platform for computing the variations in test results. In this study, three key aspects are identified to measure the performance of this device - Durability, Repeatability, and Reproducibility.

Inside cabin of a passenger car, low frequency booming noise still presents a major hurdle for NVH engineers to fine tune a vehicle. Low frequency booming noise is presently taken care with addition of mass damper and large reinforcements. These conventional countermeasures add weight to the vehicle as well as increase the overall production cost. The study presented in this paper proposes a countermeasure model that not only reduces the booming noise but also avoids any weight and cost addition. It has been focused for low frequency booming noise around 30 ∼ 40 Hz. Within the range mentioned, one of the major reasons for booming noise in hatchback models is the bending resonance of backdoor. By modifying the mode of the backdoor in such a manner that it cancels the effect of bending on the vehicle acoustic cavity, improvement can be achieved in terms of sound pressure level at the driver’s right ear location (DREL).

With the change in the perspective of the Customers towards safer vehicles, most of the Vehicle manufacturers in India are making their vehicles Crash compliant. According to the accidental data collection, Side crashes are second leading cause of death after Frontal crash. Currently sub system level tests are done for evaluating the side impact safety performance of the vehicle. One of such sub system level test is Quasi-static side door intrusion Test. The primary purpose of this testing is to measure the Force-deflection characteristics by intrusion of the impactor into the vehicle. These characteristics are controlled by various door components like door beam, latch & striker, hinge etc. This article studies the relation between Side door intrusion and Side collision, effect of above mentioned components on this relation. A theoretical study is done to study this relationship and it is substantiated with experimental data.

BIW (Body-in White) is a type of vehicle structure formed by spot welding of different sheet metal components. The BIW structure should be designed to support the maximum load potential under various performance conditions. Thus the structure should have good strength as well as stiffness. Torsion Stiffness of BIW is the amount of torque required to cause a unit degree of twist. It is often considered as a benchmark of its structural competence due to its effect on various parameters like ride, handling, lateral load distribution and NVH performance of vehicle. The paper aims to design and develop a test methodology and test fixtures for measuring the BIW torsion stiffness with repeatability of test results and also have an (R2>0.99) for the measured values in the test.

Water Wading refers to the situation where a car is moving through relatively deep water at low speed. The challenges of an automotive Original Equipment Manufacturer (OEM) is to integrate the functional parts like bumper, bumper grille, engine undercover, intake system etc., to enhance the vehicle quality and performance. One of the challenges in vehicle front end and engine room design is to prevent water entry into the air intake system during wading. If significant amount of water enter the air intake, some of the water could subsequently enter the engine cylinder, which would damage the critical components within the engine beyond repair. In general practice wading tests have been carried out during proto stage of vehicle development program to ensure vehicle performance. However a Computational Fluid Dynamics (CFD) method for carrying out water wading calculations early during the development phase offers reduction in development cost and time for a new vehicle.

Reducing the carbon footprint by meeting stringent emission regulations and improving the fuel efficiency has become an essential feature in 21st century product design cycle for automobiles. Aerodynamic drag affects the fuel efficiency of the vehicle considerably. Various drag reduction devices such as air dam, rim cover, spoiler and undercover etc. are added in order to reduce the drag. This paper aims at understanding the effect of ground clearance on the performance of various aerodynamic drag reduction devices like - air-dam, spoiler, wheel cover and their combinations for hatchback vehicle using Computational Fluid Dynamics (CFD). CFD has been extensively used for exploring the various design configurations and has helped in selecting the optimized aero-parts configuration based on aerodynamic performance at concept stage which has ultimately reduced the vehicle drag coefficient by 10%.