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Three-cylinder Engine without balancer shaft is a recent trend towards development of lightweight and fuel-efficient powertrain for passenger car. In addition, customer's expectation of superior NVH inside vehicle cabin is increasing day by day. Engine mounts address majority of the NVH issues related to transfer of vibration from engine to passenger cabin. Idle vibration isolation for a three-cylinder engine is a challenging task due to possibility of overlapping of Powertrain's rigid body modes with engine's firing frequency. This Overlapping of rigid body can be avoided either by modifying mount characteristic or by changing the position of mounts based on multi-body-dynamics (MBD) simulation. This paper explains about two types of engine mounting system for a front-wheel drive transversely mounted three-cylinder engine. The base vehicle was having three-point mounting system i.e. all three engine mounts were pre-loaded.

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.

India is a country of diversity. From North to South, east to west, one can find altogether different culture, religions, spoken languages, foods, weather conditions, people lifestyles, dressing styles etc. This vast diversity of India poses a great challenge in front of Indian Automobile Manufacturers, so as to assimilate all the requirements (of this big nation) in one single car (design). For example, many people in India wear turban (out of their religious beliefs or cultural heritage). So, is it required to keep enough consideration for Turban wearing population in vehicle design? Turban, unlike caps or hats, is something which is tied on the head (not just only kept). It is something which cannot be removed whenever required. So, it can somehow be considered as an integral part of body (as an added head dimension). So, it becomes all the more important to thoroughly understand this aspect & keep a consideration for the same in vehicle design.

Automobile Catalyst are used to convert Harmful gases emitted by vehicle (CO, HC, and NOx) to less Harmful gas (CO2, H2O and N2), Catalyst Loading comprises of Platinum, Palladium and Rhodium (Rare earth metals) metal powders combined in slurry and wash-coated onto a ceramic brick. Ever since the introduction of BS6 Emissions norm (stricter emission regulation), Catalyst loading content has increased in all vehicles. The Price of these rare earth metal are increasing day by day. Typically, a BS6 regulation catalyst contains a few grams of loading content. In some vehicles there are more than one catalyst (due to regulation requirement) and in some cases catalysts are also located in the underbody, in such cases, Number and location of catalyst makes the vehicle an easy target for thieves. Recently local police authorities around the country have captured many catalysts theft gangs.

Trunk lid (TL) can be opened using hydraulic or pneumatic balancers, coil springs, torsion bars or combination of the above. TL Opening Mechanism specific to Trunk Lid Torsion Bar (TLTB) is being discussed in the paper. After de-latching, TL should open smoothly and stop at such a height that it is visible from driver seat. The system consists of a four bar linkage mechanism, in which the fixed link is formed by BIW Bracket. Connecting link, TL Hinge Arm and Torsion bar arm form the other three links. Hinge has its one end attached to TL and the other end to BIW bracket. Torsion bar arm transfers torque to TL hinge through the connecting link. Major challenges in designing TLTB mechanism are part tolerances, C.G position and Weight variations in individual parts, Torsion bar Raw Material variation, uncertain friction in the system etc.

Riding comfort for automobile seating can be classified into two categories, long time riding comfort and short term riding comfort. The attributes that govern the riding comfort includes static spring constant and energy lost due to hysteresis. The emerging trend towards long term riding comfort could be governed by the above mentioned factors. The hysteresis loss characteristic is related to Poly-Urethane (PU) properties used extensively in automotive seating application. The nature with which the energy is released considering the same material and varying the hardness directly contributes to the comfort analysis for automobile seating and vice versa. Two curves can define the same area but the loading and unloading trend for the two cases could be different and so be the riding comfort. A conclusion would be drawn by obtaining hysteresis loss rate by changing the different parameters (hardness, density). One parameter would be varied by keeping the others constant.

Electrostatic charge generation in fabric is a common phenomenon. This phenomenon of charge generation & transfer of the same to human body is more in case of fabrics made of polyester yarns due to interface property of the material. The charge generation may result in attraction of dust on the fabric surface, clinginess & may also result in uncomfortable shock to the human body. This situation is attributed to various parameters such as fabric construction, yarn properties, yarn finish & various coating on the yarn. Since, polyester fabric is prime material used in seating; there have been many incidences of rubbing of seat fabric to human body, resulting in generation of static charge. This study focuses on understanding the effect of various fabric parameters on electrostatic charge generation. The study will also look into various potential solutions to reduce the charge generation with their merits and demerits.

The interface between human body and automotive seat contours is seat upholstery. Seating comfort has a functional correlation to the upholstery. Two seats having different upholstery will give different comfort perception. Even an ergonomically designed seat if fitted with poor quality fabric will subdue the seat comfort drastically. The effect of fabric comfort ranges from initial short term to long term comfort, driven by properties like wick-ability and factors like thermal stress. Beyond material characteristics, fabric fit also plays an important role. This paper analyses the effect of fabric parameters and construction on automotive seat comfort. A comprehensive comparative study is followed by systematic analysis and comfort improvement scope through upholstery. The research is to conclude potential of the seat fabric in enhancing the automotive seating comfort within stipulated constraints of fabric properties and cost.

As we transition towards Internet of Things (IoT) - humans are connected to each other & outside world through the smartphone. Customers tend to use smartphones for varied purposes ranging from communication to entertainment. However, the concern of distraction exists due to poor visibility & accessibility of the phone’s screen in driving condition. One of the repercussion of being connected to smartphone particularly in driving condition includes higher number of road accidents due to distraction. This paper explains one of the key initiatives taken by Maruti Suzuki India Limited to address the same.

Automobile industry is shifting its focus from conventional fuel vehicles to NexGen vehicles. The NexGen vehicles have electrical components to propel the vehicle apart from mechanical system. These vehicles have a goal of achieving better fuel efficiency along with reduced emissions making it customer as well as environment friendly. Idle start-stop is a key feature of NexGen vehicles, where, the Engine ECU switches to engine stop mode while idling to cut the fuel consumption and increase fuel efficiency. Engine restarts when there is an input from driver to run the vehicle. There is always a clash between the Engine ECU and automatic climate control unit (Auto-AC) either to enter idle stop mode for better fuel efficiency or inhibit idle stop mode to keep the compressor running for driver comfort. This clash can be resolved in two ways: 1 Hardware change and, 2 Software change Hardware change leads to increase in cost, validation effort and time.

Due to intense peak summer temperatures and sunny summers in tropical countries like India etc., achieving the required thermal comfort of car occupants without compromising on fuel efficiency is becoming increasingly challenging. The major source of heat load on vehicle is Solar Load. Therefore, a study has been conducted to evaluate the heat load on vehicle cabin due to solar radiations and its impact on vehicle air-conditioning system performance with various combinations of door glasses and windscreen. The glasses used for this study are classified as green, dark green, dark gray, standard PVB (Polyvinyl Butyral) windscreen and PVB windscreen having infrared cut particles. For each glass, part level evaluation was done to find out the percentage transmittance of light of different wavelengths and heat flux through each glass.

Vehicle cabin comfort emphasizes a specific image of a brand and its product quality. Low frequency powertrain induced noise and vibration levels are a major contributor affecting comfort inside passenger cabin. Thus, using hydraulic mount is a natural choice. Introduction of lighter body panels coupled with cost effective hydraulic mounts has resulted in some additional noises on rough road surfaces which are challenging to identify during design phase. This paper presents a novel approach to identify two such noises i.e. Cavitation noise and Mount membrane hitting noise based on component level testing which are validated at vehicle experimentally. These noises are encountered at 20~30kmph on undulated road surfaces. Sound quality aspect of such noises is also studied to evaluate the solution effectiveness.

With increase in product diversity in passenger car market, the need for NVH comfort has gained very strong foothold in every segment. This needs in depth analysis for limiting the noise at part level. Radiator Fan Module is one of such part which contributes to Cabin comfort in major way. In this paper, author is focusing on designing of RFM (Radiator Fan Module) in order to have low noise. Primary objective of RFM is to meet Heat rejection requirement with optimized air flow. Radiator Fan is primarily responsible for meeting air flow requirement within specified noise limit. For flow inducing components like Radiator Fan, there is always a trade-off between the functional requirement and the noise from various sources (Electrical / Mechanical / Flow). Design of Fan blades and Motor Support ribs in RFM is critical to improve Flow noise, i.e. Air cutting noise.

The biggest challenge in vehicle BIW design today is to make a light, cost effective and energy absorbing structure. With the increasing competition as well as increasing customer awareness, today’s vehicle has to satisfy several aesthetic and functional requirements besides the mandatory regulatory requirements. While working on global platform, it is challenging to comply with both pedestrian protection and low speed bumper impact (ECE-R42) and at the same time meeting the styling intent of reducing the front overhang. Pedestrian lower leg compliance demands space between bumper member and bumper, a condition that reduces the space available for energy absorption during low speed impact (ECE-R42). Therefore, reduction in front overhang poses a problem in meeting both the requirements with limited space. This paper outlines vehicle case study in order to optimize the design of Bumper Beam structure, for complying with regulatory requirements while satisfying the styling intent.

Infotainment has always been an important aspect of life which has made its way to car design. The cars today are much more advanced compared to their predecessors. The in-vehicle Infotainment advancements have followed the consumer electronics market in terms of technologies such as Touchscreen; App based Navigation, Voice Assistant and other multimedia services. This trend is going to expand further as smartphones have revolutionized the Infotainment domain with awareness and accessibility to customers. The Infotainment system in the cars are expected to be connected not only to the cloud but various vehicle controllers to display host of information & controls at customer`s fingertips. To design a system that supports connectivity to both cloud and vehicle is challenging in terms of cost and design for the OEMs. With focus on Indian market condition and global trends, this paper analyzes the customer expectation for Connected Infotainment system.

Gear noise and vibration in automobile transmissions is a phenomenon of great concern. Noise generated at the gearbox, due to gear meshing, also known as gear whine, gets transferred from the engine cabin to the passenger cabin via various transfer paths and is perceived as air borne noise to the passengers in the vehicle. This noise due to its tonal nature can be very uncomfortable to the passengers. Optimizing micro-geometry of a gear pair can help in improving the stress distribution on tooth flank and reducing the sound level of the tonal noise generated during the running of the gearbox when that gear pair is engaged. This technical paper contains the study of variation in noise level in passenger cabin and contact on tooth flank with change in micro-geometry parameters (involute slope and lead slope) of a particular gear pair. Further scope of study has been discussed at the end of the paper.

As per the 2018 MoRTH accident report, there were 467,044 accidents, out of which 137,726 were fatal which resulted in 151,417 fatalities. In order to get an idea of the reasons for injuries and estimate the benefits of any intervention, a mathematical model should go a long way. This study is aimed at the development of such a model to predict the injuries sustained by the occupants of an M1 vehicle. We used a detailed accident database of 'Road Accident Sampling System India' (RASSI). RASSI, since 2011, has been collecting traffic accident data scientific across various locations in India. In the data, the occupant injuries are classified as No injury, Minor, Serious and Fatal We used the data of about 4700+ M1 occupants for the study & used almost 40 input parameters to determine the outcome. Based on the data, an algorithm was developed with an overall accuracy of about 67%. The parameters represented human, infrastructure, and environment.

In a Passive suspension, a shock absorber generates damping force by pressurizing the oil flow between chambers. Typically, vehicle responds with suspension deflection, which significantly depends on damping forces and suspension velocity. Tuning dampers for various roads and steering input is an iterative balancing process. In any setting, damping force w.r.t velocity is tuned for optimum ride and handling performance. Practically, to achieve a balance between the two is a tedious task as the choices & arrangements of inner parts like piston, port, valve etc., which defines the forces set up [soft / hard] are almost infinite. The objective of this paper is to measure, objectify and evaluate the performance of two such optimum setting in various ride and handling events. A passenger car set up with an optimum soft & hard suspension damping force is studied for various ride and handling sub-attributes and their conflicts are examined in detail from a performance point of view:

Government’s focus on road safety requirements is resulting in faster adoption of stringent automobile safety regulations in India. In addition, due to changing customer preference, automobile companies are also working to provide safer vehicles in the market. Due to the complexity and high cost of the vehicle safety testing, more focus is given to development of CAE simulation technologies to validate the design for meeting regulatory norms, reducing design cycle time and number of physical tests. Safety requirement in vehicle safety regulations is to minimize the impact transfer to the occupants in case of vehicle crash. During vehicle crash condition, there is possibility that driver head may hit the gear shift lever assembly (GSLA) knob as it falls in the hitting area with respect to driver seat reference point (SRP). There is a regulatory requirement for the maximum acceleration level that is to be experienced by the driver during impact to prevent serious head injury.