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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.

With the advancement of regulatory norms in automobile industry, there is a challenge to meet performance efficiency targets, especially with a lightweight platform, while providing superior driving experience to customers. The shift towards weight optimization, makes the vehicle structure more susceptible to transfer a diverse range of noise and vibrations through body. Although most undesirable noises perceived inside the cabin can be reduced by superior technology engine mounts and NVH packaging, all such solutions lead to cost addition. Intelligent considerations in part design can be used to supplement predictable transfer paths to quell the unwanted vibrations. One such case is of the gear whine noise in certain rpm bands caused by inherent gear meshing frequency coinciding with natural frequency of an engine mounting bracket.

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.

The Auto industry has relied upon traditional testing methodologies for product development and Quality testing since its inception. As technology changed, it brought a shift in customer demand for better vehicles with the highest quality standards. With the advent of EVs, OEMs are looking to reduce the going-to-market time for their products to win the EV race. Traditional testing methodologies have relied upon data received from various stakeholders and based on the same tests are planned. The data used is highly subjective and lacks variety. OEMs across the world are betting big on telematics solutions by pushing more and more vehicles with telematics devices as standard fitment. The data from such vehicles which gets generated in high levels of volume, variety and velocity can aid in the new age of vehicle testing. This live data cannot be simply simulated in test environments. The device generates hundreds of signals, frequently in a fraction of seconds.

To promote real time monitoring, IUPRm checks has been enforced in India from Apr’23 as a part of BS6-2 regulation. Since IUPRm monitoring is representative of diagnostic frequency in real driving conditions and usage pattern. Therefore, a clear understanding of real-world driving is required to define IUPRm targets. This paper shares methodology and Validation steps for defining IUPR routes for Indian market. Methodology objective is to standardize the market operating conditions over a particular region. Selected Methodology consist of three steps: For defining IUPR route framework, first step is to have a pre-market survey to know current IUPR status and improvement areas in existing market vehicles. Second step is to define market representative localized on road routes based on the finding of Pre-market survey. Third step is to validate defined IUPR routes and correlate the output in reference to coverage of market operating conditions.

Exhaust system of an automobile is primarily employed in automobile to purify exhaust gases and reduce noise due to combustion. However, a side-effect of the above function is the increase in backpressure. As specified in various literatures, an increase in backpressure can lead to a deterioration on engine performance (Power & torque). Benefit of backpressure reduction can be further taken in terms improving the power & torque of engine or improving the fuel economy. With growing concerns related to global warming and CO2 emissions, reducing exhaust back pressure is one of the promising areas in engine design in order to improve the fuel economy of the automobile and achieving carbon neutrality targets. However, reducing the back pressure generally tends to deteriorate the noise attenuation performance of the Exhaust system.

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.

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.

In manual transmission vehicles, Clutch has direct interaction with the driver and plays a significant role in defining the drivability and NVH of a vehicle. These key performance factors depend on the interaction of diaphragm and cushion springs of a clutch. For an automobile manufacturer, it’s essential to optimize the characteristics of these springs based vehicle performance requirements. A state of the art analytical model has been developed by modeling the diaphragm and cushion spring with exponential equations. Based on these models, response functions for release load, torque build-up, and pressure plate lift have been derived. Results achieved from these response functions are correlated with test data. Key contributing factors for peak clutch pedal load, vehicle launch acceleration, and disengagement point have been identified by sensitivity analysis. Multi-objective optimization is performed to select optimized parameters for vehicle performance improvement

Increasing customer expectations of comfort and convenience inside the vehicle has resulted in OEMs working on various solutions to improve interior ergonomics and overall layout. One of the key areas of focus has been the ease of ingress into and egress from the vehicle. But with increased sharing of platforms in OEM Model Lineup, due to obvious benefits like cost and common tooling/parts, it is very difficult to achieve improved results in different vehicles (like Hatchback, Notchback, SUV etc.) but with same underpinnings. One of the commonly used approaches is provision of false flooring via floor pads for front / Rear Passengers for easy Egress-Ingress. Floor Pads are used to maintain similar comfort levels across different vehicles sharing common platform and to maintain similar relationship between Foot resting positions and Side Sill.

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.

The aim of the research was to explore and establish aspects that affect ageing of non-woven fabrics used in automobiles. One of the most vulnerable parts in a vehicle, at the behest of the customer, is the Floor Carpet. Original Equipment manufacturers are continually binging at doable options for providing low cost carpets that are functionally and aesthetically durable throughout the vehicle life. [1] Car interiors, especially carpet, must remain in impeccable condition to uphold a good resale value. Targeting the analysis of causes that affect ageing of non-woven fabric material will form the core study of the literature to follow. The establishment of which shall ascertain some viable solutions to augment quality of the contemporary non-woven automotive carpet.

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.

The automobile market is witnessing a different trend altogether - the trend of shifting preference from powerful to fuel efficient machines. Certain factors like growing prices of fuel, struggling global economy, environmental sensitiveness and affordability have pushed the focus on smaller, efficient and cleaner automobiles. To meet such requirements, the automobile manufacturers, are going stringent on vehicle weights. Using electric and hybrid power-plants are other options to meet higher fuel efficiency and emission requirements but significant cost of these technologies have kept their growth restricted to only few makers and to only few regions of the globe. Optimizing the vehicle weight is a more attractive option for makers as it promises lesser time to market, is low on investment and allows use of existing platforms.

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.

Continuously rising fuel prices and global concern on climate change have resulted in a need to deliver vehicles with increased fuel economy. This has to be achieved without compromising on performance, durability and cost. Passenger car manufacturers are looking at various ways to maximize fuel economy. Major part of fuel saving can be tapped from engine itself. This can be done by activities on engine as below: Improving overall combustion efficiency and hence BSFC Efficient thermal management. Weight reduction of engine parts or complete downsizing Hybridization. Reducing engine losses i.e. parasitic losses from auxiliaries and frictional losses. This paper is focused on the reduction of engine frictional losses (FMEP) through the use of low viscosity lubrication oils. Various factors in lubrication oil contribute to friction. Experimental approach to quantifying the effect of different parameters of lubrication oil on total engine friction is presented.

Powertrain Control development has gone through many changes in terms of process, tools and practice at all OEM's across the geography. This is mainly driven by increased number of powertrain components for control, shorter development schedules, cost control, and the need to realize the potential of electronic control to increase the performance, efficiency, safety and comfort. With the significant advancement in Powertrain Controls and additions of electronic functions, it has become imperative to automate the controller development process in the V-cycle to reduce the time and make the process more efficient while detecting any logic failures upfront at the early stage of the development cycle. Traditional practices and tools of defining the controls cannot meet new requirements. Model Based Design (MBD) approach is a promising solution to meet the critical needs of powertrain control engineering to define the control logic and validate.

Hydromount plays an important role in isolating vibration during idling. To meet ideal NVH criteria, a properly tuned Hydromount is required otherwise there will be abnormal noise due to cavitation effect. Cavitation noise is such a noise which is very difficult to identify in initial vehicle development stage. The effects of cavitation in the Hydromount become increasingly important for noise and performance goals. Cavitation is the formation and collapse of vapor bubbles in a working fluid when local static pressure falls below the vapor pressure of the working fluid. Technique to detect cavitation in Hydromount is presented in this paper. The countermeasure technique concentrates on increasing the fluid flow rate betweens fluid chambers. The results for different design countermeasure performance have been measured and the performance is compared in the vehicle. The results of vehicle level tests show the same trends as bench test results.

In developing countries steel wheel is generally used in the low end passenger cars. Steel wheel has a hole at center, known as wheel bore which give the provision for tightening & un-tightening of axle nut. Due to this hole, the surrounding parts are visible which reduces the aesthetic appearance of the wheel. To cover the center portion of the wheel, “Cap, Wheel Center” also called as “Center Cap” is used, which is an aesthetic oriented part as shown in Figure 1. Center Cap is designed in such a manner that it can be easily removed & re-fitted during the service of vehicle. This paper explains the systematic methodology to optimize the weight of the “Center Cap” without compromising the performance & aesthetic appearance. Various analytical calculations have been done to achieve base line value of the design which was further justified using CAE (computer aided engineering) to optimize the performance & weight.

Engine noise is a major source of noise inside the vehicle compartment. Recently, the quietness of the occupant cabin has become an important dimension to the quality of product. OEMs are finding it challenging to meet the customer expectations for “Powerful yet quiet” attribute. Several focused studies have been made to reduce the under hood component noise in automobiles. This paper summarizes the optimization of the vibro-acoustic sensitivity (VAS) of the engine mounts of a small car engine. The contribution of each engine mount on the structure-borne noise transfer inside the cabin is the prime focus of this study. In the current analysis, the body side and engine side mounting bracket stiffness analyses are carried out to reduce the vibro-acoustic transfer. Experimental methods like conventional FRF, on-road data acquisition and physical prototyping have been used.