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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.

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.

In a highly competitive market, one of the major challenges for an automobile designer is to lower the product cost while improving the performance. Therefore, from the vehicle comfort point of view, achieving a good ride, handling and NVH performance, while satisfying the low cost and low weight target needs attention from the concept stage of the development cycle. To achieve this balance, it is important to optimize the static and dynamic stiffness of the vehicle body. This paper focuses on the effect of vehicle body stiffness on the ride, handling and NVH parameters. It also addresses the relation between static and dynamic stiffness of the vehicle. The correlation of the stiffness values with the ride, handling and NVH performance is also studied through various experiments on the actual vehicle

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.

As automobile design has become more sophisticated, the level of noise inside the vehicle has been dramatically reduced. The sources of noise which were previously ignored have now become relatively more significant, and it has become desirable to reduce the noise from such sources. The noise from the fuel system may be low but the fact that it operates continuously whether or not vehicle is moving, makes its noise level more noticeable. So in order to achieve overall better NVH characteristics in a car it is important to minimize the noises from fuel delivery system. The current paper addresses the fuel pulsation noise from fuel delivery line and describes countermeasure approach for noise reduction using an Experiment Based Design approach (EBD).

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.

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.

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.

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.

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.

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.

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.