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Electric motor noise mitigation is a challenge in electric vehicles (EVs) due to the lack of engine masking noise. The design of the electric motor mounting configuration to the motor housing has significant impacts on the radiated noise of the drive unit. The stator can be bolted or interference-fit with the housing. A bolted stator creates motor whine and vibration excited by the motor torque ripple at certain torsional resonance frequencies. A stator with interference fit configuration stiffens the motor housing and pushes resonances to a higher frequency range, where masking noise levels are higher at faster vehicle speeds. However, this comes with additional cost and manufacturing process and may impact motor efficiency due to high stress on stators. In this paper, a thin sheet metal NVH ring is developed as a tunable stiffness device between the stator and the motor housing. It is pre-compressed and provides additional torsional rigidity to mitigate torsional excitations.

With reference to present literature, most OEMs are working on reducing product development time by around ~20%, through seamless integration of digital ecosystem and focusing on dynamic customer needs. The Systems Engineering approach focuses on functions & systems rather than components. In this approach, designers (Computer Aided Design) / analysts (Computer Aided Engineering) need to understand program requirements early to enable seamless integration. This approach also reduces the number of iterative loops between cross functions thereby reducing the development cycle time. In this paper, we have attempted to tackle a common challenge faced by Closures (Liftgate) engineering: meeting slam durability fatigue life while replicating customer normal and abusive closing behavior.

The world is moving towards E-mobility solutions and Battery Electric Vehicles (BEVs) are the main enabler towards it. Li-ion cells are the fundamental building block of any BEVs. There are three common types of Li-ion cell design i.e., cylindrical cells, Prismatic Cells and Pouch cells. Ensuring safety of BEVs are critical to gain customer trust and acceptance over Internal Combustion Engine (ICE) vehicles. EV fire is found to be one of the major concerns related to using higher energy batteries. During a crash event, Post-Crash Electrical Integrity of the BEV is to be ensured and hence primary focus is on mitigation of Li-ion cell internal short circuit. It has been seen in prior published articles that cell internal short circuit can be triggered by physical intrusion of cell. This paper primarily focusses on simulating the mechanical behavior of cylindrical cell under various crush conditions.

Numerical simulation of lithium-ion batteries (LIB) has become extremely vital in the understanding of thermal behaviour of LIBs to develop active and passive battery thermal management systems. The LIB is popular in consumer electronics. Beyond consumer electronics, the LIB is also growing in popularity for the automotive applications such as hybrid electric vehicles (HEVs) and battery electric vehicles (BEVs) due to its high energy density, high voltage, and low self-discharge rate. High amount of heat generally gets developed during charge and discharge of LIB based on the c-rate at which it is being discharged or charged. Hence, there should be a mechanism to understand the thermal behaviour of these cells. Thus, in this paper a numerical procedure has been developed to model electrochemical-thermal behaviour of commercially available 21700 Li-ion cells. NewmanP2D approach is used to arrive at electrochemistry performance of Li-ion cell and pack.

Automotive headlamp designs have evolved considerably over the years, shifting from a utilitarian component of a vehicle to being a major part of its overall styling, particularly for the Front of the vehicle. In addition to this, Headlamps are a ‘mission-critical’ safety feature, especially for driving at night or in poor weather conditions. For this reason, they are subject to high performance requirements and must meet stringent automotive and highway safety standards. Modern headlamps are becoming bigger and heavier to accommodate attractive features like DRL lamps, Projector lamps and Adaptive lamps. The increased weight of the headlamp poses additional challenges with respect to the durability and loss of bolt preload during high road load events.

Stamped components play an important role in supporting various sub-systems within a typical engine and transmission assembly. In some cases, the stamped components will not initially meet the design criteria, and material may need to be added to strengthen it. However, in other cases the component may be overdesigned, and there will be opportunities to reduce mass while still meeting all design criteria. In this latter case, multiple CAE simulations are often performed to enhance the component design by varying design parameters such as thickness, bend radius, material, etc., The conventional process will assess changes in one parameter at a time, while holding other parameters constant. Though this helps in meeting the design criteria, it is often very difficult to produce the best optimized design within the limited time span with this approach. With the aid of Altair-HyperMorph techniques, multiple design parameters can be varied simultaneously.

The main objective of crash sensing is to predict a vehicle collision early in the event and command vehicle’s occupant protection systems to take appropriate actions to reduce the severity of crash injury. Currently Computer Aided Engineering (CAE) models are being used to predict the sensing signals with sensors placed at front end structure of the vehicle. The front-end structure as well as other critical components packaged in the front end play important role in absorbing energy and provide sensing signals during impact, headlamp being one such critical components. The headlamp with its lens being the exterior surface, experience large magnitude of loads from barrier during full frontal, angled and offset impact. The impact with barrier usually results in scattered damage to the headlamp and its lens. In this paper, CAE model of headlamp has been improved to reflect similar deformation pattern as observed in physical tests.

Hyper-elastic seals are extensively used in automotive applications for sealing various joints in assembly. They are also used in sealing battery packs. They are used in various sizes and shapes. Most of the gaskets used are solid gaskets. Hollow gaskets are also being used. Hollow gaskets typically have a fluid like air trapped inside. Analyzing these hollow gaskets also requires involving the physics of the fluid inside. The trapped fluid affects the performance of the gasket like contact pressure and width. Objective of this study is to analyze the hollow gasket performance including the effect of air trapped inside. The effect of air on performance of the hollow seal is also studied. Fluid Cavity capability in ABAQUS was selected after literature study to simulate the effect of trapped fluid (Air) on seal performance.

Turbochargers are widely employed in internal combustion engines, in both, diesel and gasoline vehicle, to boost the power without any extra fuel usage. Turbocharger comes in different sizes based upon the boost pressure to increase. Capacity of turbocharger are available in great range in the market which are designed to match the requirement. From structural point of view, key component of an automotive turbocharger is rotor. This rotor consists of compressor wheel, turbine wheel, shaft and bearing (journal/ball) mainly. In industries, design & development of turbocharger rotor for its dynamic characteristics is done using virtual engineering technique (Computer Aided Engineering). Multibody dynamic (MBD) analysis simulation is one of the best approaches which is used to study the rotor in great details. In this current MBD procedure fluid-structure interaction problem is solved by modelling oil film in the journal bearing and solving it using “Reynolds equation”.

Traction Control System (TRCS) has become a standard feature for most of the vehicles due to safety considerations. The system provides better drivability and acceleration performance on low friction surfaces. The TRCS typically tries to maintain slip value to an optimum value to maximize traction force by modifying engine torque and/or brake force intervention. However the optimum slip value is not a constant value and varies depending upon the road surface and tyre conditions. It is challenging task to predict this value dynamically and adapt TRCS under all driving situation. This paper presents an adaptive traction control system which tries to operate at optimum slip point irrespective of prior knowledge of road condition. The system continuously monitors vehicle dynamics parameters and corrects itself to maximize available traction. The controller has been developed using Matlab Simulink platform.

Electronics is widely used for improving the vehicle safety due to its characteristics like fast response, multi sensor interface and implementation of complex control strategy. Already a majority of vehicles are fitted with some kind of Electronic Stability Program (ESP) system in many countries to improve safety performance. Yaw stability is one of the major elements under ESP system. A project was undertaken to develop Yaw Stability Control (YSC) strategy. YSC strategy development is very challenging due to several issues like dynamics of event, ability of brake hydraulics and /or Engine torque controller to respond, proving of the strategy under different user scenarios etc. This paper describes the challenges faced and solutions tried out while development. The paper presents the YSC controller strategy, different regulatory requirements, test data and results with and without YSC on a typical SUV vehicle. The controller has been developed using Matlab Simulink environment.