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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.

With the advent of upcoming stringent automobile emission norms globally, it is inevitable for original equipment manufacturers (OEMs) to shift towards greener alternatives. Use of compressed natural gas (CNG) is a preferred solution as it is a relatively clean burning fuel and it doesn’t have significant loss in vehicle efficiency and performance. Modern day customers are more aware and sensitive towards vehicle noise, vibration and harshness (NVH). Hence, OEMs must cater to this demand through optimized design and layout. In a passenger vehicle, CNG is stored at high pressure and delivered to injectors after pressure reduction at a regulator. During engine idling, the opening and closing motion of the CNG injector generates back pulsation and these pulsations cause vibrations which may propagate through other components in the delivery path and perceived as noise inside vehicle cabin.

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

During the conceptualization of vehicle, it is big challenge for automotive manufacturer to design a vehicle which has an excellent aesthetic looks as well as meet the stringent vehicle regulations. In the vehicle styling, bumper plays an important role in deciding of the contemporary looks of the vehicle. To improve customer satisfaction, it is important to design a bumper which provides feeling and sense of durability. In addition, bumper should sustain low-speed impact and protects the peripheral components such as parking lights, headlamps, hood, back door and safety related installed equipments like Rear parking camera, parking sensors, etc. Bumper should be dent resistant and be able to regain its original shape on removal of the applied load. An elegant design of bumper should be light weight with high strength. This paper explains about a new CAE methodology developed to simulate the real life loading condition of bumper and to calculate the deformation in the bumper.

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.

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.

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.

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.

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.

Computational Fluid Dynamics (CFD) is used extensively in the optimization of modern passenger car to meet the ever growing need of higher fuel economy, better engine and underbody cooling. One of the way to achieve better fuel economy is to reduce the vehicle overall resistance to flow, know as drag. Vehicle drag is a complex phenomenon governed by vehicle styling, component shape, layout and driving velocity and road conditions. To reduce the drag a lot of aero-parts are used these days such as air-dam, skirts, spoiler, undercover, dams etc. However the design of these aero-parts must be optimized to get the desired result as their addition alone does not guarantee improvement in performance. This paper aims at studying the effect of air-dam height and position on vehicle aerodynamics. Also the effect of air-dam addition was verified using fuel economy simulations.

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.

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.