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In the modern automobile scenario in developing countries, customers are getting more meticulous and market more competitive. Now even the budget vehicle customer expects desirable vehicle performance in specific use cases of the vehicle that were previously not focused by designers. Hence, the focus on perceived quality challenges automobile engineers to go the extra mile when it comes to the cost-effective design of parts that are tangible to the customer. A vehicle's cowl cover is one such exterior component. The primary functions of this part are to provide air intake opening for the HVAC system and cover the components like wiper motor. The aesthetic function is to cover the gaps between windshield, hood, and fender as seamlessly as possible. A specific role of cowl cover, which calls for a designer's attention, is its load-bearing capability.

With ever increasing demand for vehicle safety and fuel efficiency, Body in White (BIW) designers are striving for vehicle's body mass optimization leading to the development of lean designs. Nevertheless, considerations like ergonomics also play a significant role while deciding the vehicle structure. As an example, A-pillar (front pillar) plays a major role in vehicle's passive safety. Increase in its cross section size, beyond a particular grade and gauge optimization is eminent to meet target requirements of rigidity and crash. However, the increased obstruction because of the wider section would not only lead to poor visibility and a claustrophobic feeling to the driver but also lead to a lesser response time for him or her to prevent a collision. Obstruction from A-pillar can be a subjective feeling of driver but it should also be quantified and measured to optimize the A-pillar structure. Numerous methodologies are being adopted globally to measure the A-pillar obstruction.

Automotive OEMs quest for vehicle body light weighting, increase in Fuel efficiency along with significant cut in the emissions pose significant challenges. Apart from the effect on vehicle handling, the reduction of vehicle weight also results in additional general requirements for acoustic measures as it is an important aspect that contributes to the comfort and the sound quality image of the vehicle, thus posing a unique challenge to body designers and NVH experts. Due to these conflicting objectives, accurate identification along with knowledge of the transfer paths of vibrations and noise in the vehicle is needed to facilitate measures for booming noise dampening and vehicle structure vibration amplitude. This paper focuses on the application of a unique design and development of vehicle body structure anti-vibration dynamic damper (DD), unique in its aspect in controlling booming noise generated at a specific RPM range.

Offset crash compliance of a compact car is severe due to the compact layout and stringent fuel economy, weight and cost targets. Scope of the current work is to improve the structural crash performance of a compact car through CAE, in order to meet the offset frontal crash requirements as per ECE R94 Regulation. The project has been classified in three main phases. First phase includes the evaluation of baseline vehicle in CAE. In order to ensure the accuracy of CAE prediction, a methodology for predicting Spotweld rupture was implemented. Using this methodology, it is possible to find out the location and time of spotweld rupture as well as propagation of spotweld rupture in CAE. CAE results of spotweld rupture prediction showed good agreement with the physical test. In second phase, design iterations were carried out in order to meet the performance targets of structural deformation.

Front end accessory drive (FEAD) system explained in this paper is a sub-system of an engine. In FEAD system, a poly-v belt is used to drive the alternator and water pump by transmitting power from crankshaft pulley. In a new vehicle development program, durability targets of FEAD system are based on required life of poly-v belt, its static tension readjustment interval and replacement frequency. To meet these durability targets following methodology is applied in design stage:- 1 Simulation of FEAD system to calculate the theoretical life of belt 2 Part level testing of belt as per SAE J2432 These methods give sufficient information on belt durability. However in actual usage, certain failures are prone to happen and enormous difference is always observed between theoretical and actual life of belt. This paper describes the traditional stair-case approach followed to optimize the FEAD system based on the outcome of durability tests.

This article brings a practical analysis for determination of gravity center in unsymmetrical three dimensional bodies practically and graphically. The gravitational center of an object is the point from which if suspended, the object remains stable at all times, this is also called as center of mass of the object, or the theoretical point at which the entire weight of the object is assumed to be concentrated. In certain tests, the Center of Gravity (CG) of the Seat is required to be known, for load application. The CG is the point at which a SEAT would balance if it were possible to suspend it at that point. This paper deals with use of applied engineering and theoretical calculations to ascertain the CG of First and Second Row seats (individual and bench type). In this case the center of gravity location is expressed in units of length along each of three axes (X, Y and Z). Load balance equation is used to calculate the CG of the seat.

Road accidents are a major concern worldwide and vulnerable road users make up more than half of the victims of road accident deaths. In order to combat this issue, several countries worldwide have mandated pedestrian safety test regulations viz., AIS100 & UN-R127. One of the requirements of the regulations is when Flexible Pedestrian Legform Impactor (Flex-PLI) is impacted onto the frontal structure of the vehicle at a speed of 40kmph, the Bending moment (BM) of tibia bone of Flex-PLI shall not exceed the regulatory limit of 340Nm. In this paper, we have built a statistical model for predicting the BM of tibia in Flex-PLI using regression analysis. 13 vehicles have been selected from all applicable vehicle categories viz., Sedan, hatchback, Coupe & SUV/MUV for this undertaking. An exhaustive analysis of the vehicle frontal structures and Flex-PLI test videos have been done to identify & measure the design parameters to be used as predictor variables.

Clutch actuation system in manual transmission is one of the key systems of power-train with which driver interacts frequently. Therefore its load and travel feeling are important to customer. Clutch actuation system consists of clutch pedal assembly, flexible cable mounted on body panel, and clutch release arm/ shaft assembly inside transmission unit assembly. Clutch pedal load, travel and engagement point are important parameters to specify the actuation feeling while designing the clutch actuation system. Validation of actual values is being done at proto vehicle testing stage, as final output calculation may not be accurate due to dependency on variables difficult to estimate. To overcome these difficulties a virtual dynamic model of the entire clutch actuation mechanism has been created in MBD software. Model input factors are based on actual testing results to improve the accuracy. The model predicts the clutch pedal load and travel values for a given set of vehicle inputs.

The Indian passenger vehicle market has grown by more than 40% by volume in the last decade and has reached a record high in FY23. This has created a more diverse and demanding customer base that values interior design and quality. The modern customer expects a high level of aesthetics and sophistication in their vehicle interiors - including in the luggage area. The Luggage Cover (Parcel Tray) is a component in the luggage area of a passenger vehicle that is used to conceal the luggage & improve its aesthetics. The cover is generally made of thermoplastic material with rotating hinges and is held in its place by the compression from the back door, which is frequently opened and closed. The parts that connect the cover to the door (usually an elastomer interface on the thermoplastic tray) tend to change over a period due to climatic conditions and leads to rattling concerns over a period.

Plastic plays a major role in automotive interiors. Till now most of the Indian automobile industries are using plastics mainly to cover the bare sheet metal panels and to reduce the weight of the vehicle along with safety concerns. Eventually Indian customer requirement is changing towards luxury vehicles. Premium look and luxury feel of the vehicle plays an equal role along with fuel economy and cost. Interior cabin is the place where aesthetics and comfort is the key to attract customers. Door Trims are one of the major areas of interiors where one can be able to provide premium feeling to the customer by giving PVC skin and decorative inserts. This paper deals with different types of PVC skins and its properties based on process constraints, complexity of the inserts. Door trim inserts can be manufactured by various methods like adhesive pasting, thermo-compression molding and low pressure injection molding process etc.

In laboratory car crash tests, Anthropomorphic Test Devices (ATD) are equipped with piezoresistive and resistive sensors for occupant injury assessment. Accelerometers are inertial transducers that convert acceleration into electrical output which can be easily recorded by a Data Acquisition System (DAS). For an accelerometer, this electrical output mainly depends upon subjected acceleration, sensitivity of the accelerometer, excitation voltage and gain provided. Before use in testing, accelerometers are calibrated at a standard excitation (manufacturer decided) voltage to determine characteristics like Sensitivity, Sensitivity per unit excitation voltage, Zero Measurand Output (ZMO), Transverse Sensitivity etc. It is observed that these characteristics are highly dependent on the excitation voltage. In testing, due to limitations of DAS and/or other unwanted noise in the excitation voltage, these accelerometers are sometimes used at a different excitation voltage.

Single body architecture designed for various global markets and subjected to varied load cases is a challenge for Body in White (BIW) engineers. Optimization of structural design to meet regulatory, insurance and assessment requirements is an iterative and time consuming task. With focus on reduction of vehicle's damageability and ease of repairability Original Equipment Manufactures (OEM), insurance companies and Research Council for Automobile Repairs (RCAR) [1] are striving for better designs. A space constraint crash box structure installed behind the bumper plays a significant role in absorption of energy, before transmitting to longitudinal rails. In this study, crashworthiness of a multipurpose crash box for a hatch segment vehicle is presented with the various design of experiments conducted with a focus on light weighting, cost and ease of manufacturing.

Seats, seat belts, seat belt anchorages, etc., are safety critical items for the passenger in case of sudden acceleration/deceleration and accidents. Seat belts have become mandatory fitments on front seats of M and N categories of vehicles from April 1994 in India[1]. Seat belt without a proper anchorage does not serve any purpose. Hence, seat belt anchorage testing became mandatory in India in year 2002. In real accident situation seat belts come in to action within few ms and complete phenomenon is finished in 150 ms. However the regulatory requirements prescribed in AIS: 015, ECE R14 and 76/115/EEC specify the application of loading to be achieved as rapidly [2].A number of seat belt anchorage tests were conducted on BIW and laboratory model setups. This paper highlights the effect of loading rate, and loading method on the load bearing capacity of the seat belt anchorages, floor area and seat structures.

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.

Head form impact tests are carried out on instrument panel as part of meeting the requirements of the interior fitting regulation ECE R21. India adopted the ECE R21 regulation and interior fitting impact tests became mandatory in April 2005 for models manufactured from April 2005 and April 2006 for models being manufactured before April 2005. Energy dissipation testing of vehicle’s interior fitments is done at various selected and defined locations. With the implementation of interior fitting regulation in India, it is mandatory that every manufacturer tests and certifies their product to comply with the energy dissipation standards as defined in the regulation ECE R21. Extensive interior fitting test program is carried out for various models ranging from MY1993 to MY2003.During the development testing following types of failures were observed: Occurrence of surface cracks due to sharp edges and component dislocation.

Recent advancement in numerical solutions and advanced computational power has given a new dimension to the design and development of new products. The current paper focuses on the details of work done in order to improve the vehicle performance in Offset deformable Barrier (ODB) crash as per ECER-94. A Hybrid approach involving the Structural Crash CAE as well as Multi-body Simulation in MADYMO has been adopted. In first phase of the development, CAE results of Structural deformation as well as Occupant injury of the baseline model were correlated with physical test data. The second phase includes the improvement in intrusion and crash energy absorption by structural countermeasures in the vehicle body. In third phase parametric study has been carried out via Madymo simulation in order to decide on the factors which can be controlled in order to mitigate the Occupant injury. Recommendations of Madymo simulation have been confirmed by conducting Physical sled tests.

The side impact accident is one of the very severe crash modes for the struck side occupants. According to NHTSA fatality reports, side impact accounts for over 25% of the fatalities in the US. Similar fatality estimates have been reported in the EU region. Side crash compliance of a compact car is more severe because of the less space available between the occupant and the vehicle structure, stringent fuel economy, weight and cost targets. The current work focuses on the development of Side body structure of a compact car through Computer Aided Tools (CAE), for meeting the Side crash requirements as per ECE R95 Regulation. A modified design philosophy has been adopted for controlling the intrusion of upper and lower portion of B-pillar in order to mitigate the injury to Euro SIDII dummy. At first, initial CAE evaluation of baseline vehicle was conducted.

Increased engine thermal load, front end styling and compact vehicle requirements have led to significant challenges for vehicle front end designer to provide innovative thermal management solutions. The front end cooling module design which consists of condenser, radiator, fan and intercooler is an important part of design as it ensures adequate heat removal capacity of radiator over a wide range of operating conditions to prevent overheating of engine. The present study describes the optimization of cooling air flow opening in the front end using CFD methodology of a typical passenger car. The predicted vehicle system resistance curve and coolant inlet temperature to the radiator are used for the selection of cooling modules and to further optimize the front end cooling opening area. This leds to the successful optimization of the front end, selection of cooling modules with significant cost savings by reducing prototype testing and design cycle time.

Use of safety belts inside a vehicle is necessary to ensure the safety of passengers as well as drivers. To promote the use of seat belts, a seatbelt reminder system is utilized. This system incorporates a sensor for checking seat occupancy for the passenger seat. Activation of these sensors depends on various parameters like seat pad shape, seat upholstery, vehicle H-point, a load on the seat, etc. In this study, the load factor on the seat is studied. The load on the seat may come from occupants or due to the objects placed on the seat. The detection of objects as an occupant may result in false seat belt reminder alarm and cause inconvenience to the customers. Subjective analysis and surveys, covering a broad range of market population, were done to identify such objects. Consequently, performance requirements were determined to facilitate sensor optimization and selection.

The outside visibility through the windshield and ORVM visibility through the side glasses are critical for safe driving. The frost deposition on the Windshield and side glasses in the cold climatic condition impairs the outside and ORVM visibility during driving and hence leads to an unsafe driving condition. In India, the regulation AIS-084 governs the defrosting standard. The defrosting performance evaluation by testing cannot be performed at concept stage when the vehicle prototype is not available. It also increases the cost of vehicle development due to increase in the number of prototype used for testing. This paper explains about the in-house developed CFD methodology to evaluate the windshield defrosting performance of the vehicle in the concept stage when no vehicle proto is available and cost of countermeasure for defrosting performance improvent is very less. This methodology is implemented for some of the existing models.