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The Indian automotive industry is going through a rapid transformation phase. Regulatory emission norms such as, migration from BSIV to BSVI engine, increased adoption of μ-hybrid, full electric and autonomous cars are examples of such rapid transformation. The upgradation of internal combustion engines for compliance with new regulatory norms (e.g., from BSIV to BSVI) has caused a significant change in the automotive acoustic performance. As the powertrain system are being upgraded and getting quieter, the on-board Heating, Ventilation and Air-Conditioning system (HVAC) system emerges as one of the prominent noise sources which strongly influences overall refinement levels inside the cabin. This in turns is affecting overall feeling of passenger’s comfort. The HVAC system of an automobile is a compact and yet a complex system designed to provide thermal comfort inside the car cabin.

In electric vehicles, the powertrain mounting system design has challenges different from conventional internal combustion engine (ICE) powertrains. Due to the absence of source noise, the customer predominantly experiences the buzz, squeak and rattle (BSR) noise. The 6 degrees of freedom (DOF) modal frequency target is less stringent than a three-cylinder or four-cylinder ICE powertrain. The durability loads in EV also differ due to less powertrain weight. In this paper, a study has been carried out about balancing all three main performance parameters of modal decoupling, BSR and durability through powertrain mount design optimization. The article shows that a carryover ICE powertrain mount has typical issues in Electric Vehicle (EV). A case study has discussed in detail how to manage those issues. Finally, it is concluded that a particular focus is required during an early stage of mount design to address these challenges for an EV.

For a modified electric vehicle on the same internal combustion engine (ICE) platform, the primary consideration is to have no change in long member and pendulum type conventional engine mounting system to save development cost and timeline. Electric vehicle (EV) powertrain is comparatively lighter w.r.t the ICE. As a result, the engine mount’s static preload setting point or powertrain centre of gravity under static powertrain load gets changed resulting in a change in stiffness for the same engine mount. As the static stiffness changes, the dynamic stiffness and modal frequency also change. The 6 degrees of freedom (DOF) modal frequency has almost no impact on powertrain modes as EV powertrain modes, mainly, the motor frequency, is much higher than engine mount Eigen modes. In this scenario, the gap management gets disturbed due to less static preload, and non-linearity gets affected.

In an automotive braking system, Vacuum pump is used to generate vacuum in the vacuum servo or brake booster in order to enhance the safety and comfort to the driver. The vacuum pump operation in the braking system varies from conventional to electric vehicles. The vacuum pump is connected to the alternator shaft or CAM shaft in a conventional vehicle, operates continuously at engine speed and supplies continuous vacuum to the brake servo irrespective of vacuum requirement. To sustain continuous operation, these vacuum pumps are generally oil cooled. Whereas in electric vehicles, the use of a motor-driven vacuum pump is very much needed for vacuum generation as there is no engine present. Thus, with the assistance of an electronic control unit (ECU), the vacuum pump can be operated only when needed saving a significant amount of energy contributing to fuel economy and range improvement and emission reduction.

The public transport in India is gradually shifting towards electric mobility. Long range in electric mobility can be served with High Voltage Battery (HVB), but HVB can sustain for its designed life if it’s maintained within a specific operating temperature range. Appropriate battery thermal management through Battery Cooling System (BCS) is critical for vehicle range and battery durability This work focus on two aspects, BCS sizing and its coolant flow optimization in Electric bus. BCS modelling was done in 1D CAE software. The objective is to develop a model of BCS in virtual environment to replicate the physical testing. Electric bus contain numerous battery packs and a complex piping in its cooling system. BCS sizing simulation was performed to keep the battery packs in operating temperature range.

Spot-weld joinery plays a major role in maintaining structural integrity of vehicle during an accident scenario. Robust failure definitions are important for accurate prediction of spot-weld failure in crash safety simulations. Spot welds have a complex metallurgical structure, consisting of fusion and heat affected zones. Identifying material failure definitions for huge number of spot-weld joint combinations in a typical Body in White (BIW) of a vehicle is highly challenging. In conventional LS-DYNA-MAT100 material model, spot-weld failure prediction accuracy is limited under complex crash loading scenarios, especially angular and bending load conditions. In order to enhance the failure predictions, a novel mathematical failure model is developed by considering instantaneous resultant loading along with bending moment as a key failure parameter to determine spot weld joint failure.

Electric vehicles are fast expanding in market size, and there are increasing customer expectations on all aspects of the vehicle, including its noise and vibrational characteristics. Irritable noise from traction motors account for around 15% of the overall noise in an electric vehicle, and thus, has a need to be analysed and studied. This study focuses on identifying the critical vibro - acoustic orders for an 8 pole PMSM (Permanent Magnet Synchronous Motor) for three cases - healthy, with static eccentricity and with dynamic eccentricity. PMSM motors are widely used for traction and other applications due to their higher power density along with compact size. A coupled approach between electromagnetic and vibro - acoustic simulation is deployed to characterise the NVH behaviour of the motor.

Tailgate stoppers play vital role in exerting preload on the Tailgate latch mechanism and also restrict the relative motion of the Tailgate against vehicle Body in White (BIW). These stoppers act as over-slam dampeners and reduce the transmissibility of vibrations thereby reduce the risk of Squeaks & Rattles (S&R) noises. S&R noises from Tailgate are most annoying to the rear passengers in the vehicle and are recurring in nature. Preventing these issues during design is a challenging task. S&R risk simulations enable us to conduct virtual Design of Experiments (DOEs) and arrive at optimal solutions. This approach helps in reducing the cost of the design changes that are required in the physical prototype at the later stages of product development and save time. The risk evaluation in the simulations is based on the relative displacement at the interfaces of two components.

The main objective of the exhaust system is to offer a leakage proof, noise proof, safe route for exhaust gases from engine to tailpipe, where they are released into the environment, while also processing them to meet the emission norms. New stringent emission norms demand ‘near-zero’ leakage exhaust systems, throughout vehicle life bringing the joints into focus as they are highly susceptible to leakage. Needless to say, this necessitates them to endure not only structural but also the environmental loads, throughout their life. Thus, the fatigue life or durability tests become the most critical part of the exhaust system development. Test acceleration and result correlation (for life prediction), to meet the stringent project timelines and stricter environmental norms are the key considerations for developing a new testing methodology. Quality of accelerated tests is ensured by deploying all possible multiple loads, to simulate real-life conditions.

Automotive door seal has an important function which is used extensively where interior of the vehicle is sealed from the environment. Problem with door seal system design will cause water leakage, wind noise, hard opening or closing of doors, gap and flushness issue which impair customer’s satisfaction of the vehicle. Moreover, improper design of seal can lead to difficulty in installation of door seal on body panel. The design prudence and manufacturing process are important aspect for the functionality and performance of sealing system. However, the door sealing system involves many design and manufacturing variables. At the early design stage, it is difficult to quantify the effect of each of the multiple design variables. As there are no physical prototypes during rubber profile beading-out stages, engineers need to carry out non-linear numerical simulations that involve complex phenomena as well as static and dynamic loads for door seal.

The recent vehicle development demands for electric powertrain as against conventional fuels engines. The electric powertrain offers advantages in terms of cleaner and quieter operations. In electric vehicle, the conventional engine is replaced by electric motor operated on batteries. Here, the conventional engine refers to those powered by diesel, petrol, CNG and some hybrid vehicles using fuel as primary source for power generation. Thus, the system design approach for mount also changes. At present, various approaches are being followed to mount electric powertrain like conventional pendulum type, with or without cradle, Common or different motor and electric box mountings etc. The electric powertrain differs from conventional powertrain in terms of weights, mass moment of inertia, torque, NVH requirements like Key in Key off, idling, low frequency vibrations etc. Thus conventional mount will not necessarily meet NVH requirements for Electric powertrains.

Today's automotive industry demands high quality component as well as system designs within very short period of time to provide more value added features to customers on one hand and to meet stringent safety standards on the other. To reconcile economy issues, design optimization has become a key issue. In the last few decades, many OEMs took to analytical tools like Computer-Aided-Engineering (CAE) tools in order to decrease the number of prototype builds and to speed up the time of development cycle. Although such analytical tools are relatively inexpensive to use and faster to implement as compared to the costly traditional design and testing processes: however, there are many variables that CAE tools cannot adequately consider, such as manufacturing processes, assembly, material anisotropy and residual stresses. Therefore, still smart measuring and testing techniques are required to substantiate the CAE results.

Electrical and Series Hybrid Vehicles are generally provided with single speed reduction gearbox. To improve performance and drive range, a two-speed gearbox with coordinated control of traction motor and gearshift actuator is proposed. For a two-speed gearbox, gearshift without clutch would increase the shifting effort. Active Synchronization is introduced for a smoother gearshift even without clutch. The quality of gearshift is considered as a function of applied shift force and time taken. To enhance the quality of the gearshift further, the location of the synchronizer in the transmission system is optimized. To validate the improvement in the quality of the gearshift, a mathematical model of the two-speed gearbox incorporating proposed location of synchronizer assembly along with active synchronization is developed. The qualitative and quantitative analysis of the results achieved is presented.

As the automobile industry in India is growing fast and competitive, there is a need to design the vehicle and its parts at most cost effective. This paper gives the details of design optimization and cost effective methodology followed to develop a Single Stalk Combination Switch, without degrading the end user delight. This paper describes various design criteria affecting the combination switch design.

Basic Function: Vehicle remote is used for vehicle lock/unlock/search/Hazard lights /approach light functions for customer convenience and vehicle security system. Conventional approach: 1 Use of separate RF (Radio Frequency) receiver -Additional Cost impact. 2 High remote RF power - Reduced remote battery life and bigger remote size required 3 High sensitivity RF receiver - High cost. Low Cost approach: It involves the followings: 1 Integration of RF receiver inside the Body Control Module (BCM). 2 Low Power Remote and Optimization of Remote PCB layout to get the maximum power. 3 External wired antenna taken out from BCM and proper routine need be ensured to get the best performance. 4 BCM mounting location to get the best remote range in all vehicle directions. This paper relates to the methodology for low cost approach for the RF communication between remote transmitter and receiver with achieving the best remote performance at vehicle level condition.

Power-supply forms a key hardware block for every automotive ECU. Apart from delivering robust and reliable logic supply voltages it is also burdened with many auxiliary tasks like transient protection, good EMI/EMC performance, Power-hold function, Analog Sensor supply voltage etc. It also needs to meet all automotive norms including short to battery/ground etc. This paper discusses low cost implementation techniques which maximize the value delivered to the vehicle application at minimal cost. Innovative techniques are described for combining sensor and logic supplies wherever applicable. Hurdles faced during such circuit optimization are clearly explained along with the solutions adopted to overcome hurdles yet meeting automotive test norms. A novel low cost concept which combines transient protection as well as power-hold function (without using the conventional relay based technique) further adds value to the end application.

S.A.V.E. (SOLAR-ASSISTED VEHICLE ELECTRICAL SYSTEM) is a microcontroller-based closed loop system designed to optimize the duty cycle of alternator in conventional vehicle electrical system. This has been done by integrating a SOLAR PANEL on the rooftop of a popular hatchback. The SOLAR PANEL supplies continuous power to battery for charging thereby reducing alternator duty cycle. Consequently, in order to optimize/control alternator functioning based on demand, a microcontroller has been incorporated. S.A.V.E. consists of a microcontroller which senses the instantaneous electrical load (in terms of current & voltage drawn) from battery. The controller using the intelligent algorithm keeps on checking this real-time consumption with the threshold values & decides when to activate/deactivate alternator. Thus with this controller, a) reduction in actual CO₂ emission & consequent, and b) 6% improvement in vehicle fuel efficiency has been achieved.

Automotive Industry is constantly upgrading the value offered on their products at optimized cost. Scratch and mar resistance of interiors and exterior parts, is an important attribute which is linked to perceived quality and value offered to customers. Polypropylene material is optimum material of choice for these parts due to its unique advantages. However, filled polypropylene material has poor scratch and mar resistance. Many techniques for scratch resistance improvement are available such as additions of slip agents, co additives, special fillers, siloxanes, etc. However, some of them may offer some disadvantages like stickiness or tackiness on the surfaces. The choice depends on its effectiveness & cost. This paper deals with design of experiments to evaluate effectiveness of 4 types of additives and their optimum % to give scratch resistance improvement without having detrimental impact on other critical properties.

The growing demand of fuel and cost saving on vehicle, today’s vehicle manufacturer are working on various weight reduction initiative in EV. Lighter weight vehicle have bigger challenges to meet NVH requirement. There are two types of EV called modified and adopted EV’s are commonly in use. The sub frame type of EV system comes under the category of modified EV. In this paper, a mounting system is studied and compared for a cradle type EV as well as sub frame or saddle type EV. MATLAB based optimization tools are used for parameter optimization. The focus is put on the optimization of mounting system location and stiffness for energy optimization, CoG and TRA-EA optimization. The best engine mounting system is compared and adopted based on simulation. 12 DOF studied to address high frequency resonance issues for a sub frame type EV. Finally robustness of the system is checked based on various simulation and optimization.

There are two types of EV (electric vehicle) currently in use, namely modified EV and dedicated EV. Generally, we use a modified EV in cost-sensitive markets where we can commonize platform between internal combustion engine (ICE) and EV vehicles. For modified EV, we use the cradle to support the powertrain components, which connects to the engine mount, which in turn attaches to extended members and subframe. The fabricated cradle has many welding components that cause dimensional variation at the rear-mount attachment point on gearbox, which creates a reduction in the dynamic envelops significantly. The decrease in clearance often results in BSR noise, which we have simulated in the rig as well as on rope track. On a rough road, this noise is predominant. This buzz, squeak and rattle (BSR) noise also results in Tip in/Tip out noise, which is quite uncomfortable for the customer during sudden acceleration and deceleration.