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Vehicle manufacturers strive hard to achieve best in class fuel economy. Apart from light weighting of the structures, driveline optimization and reduction of tire rolling resistance, tapping of parasitic losses is also important and helps to optimize the design of auxiliary power consuming systems. One of such system studied in this work is power steering system. The effect of parasitic losses on fuel economy is predominant for small commercial vehicle compare to heavy vehicles. The evaluation of deterioration in the fuel economy due to implementation of power steering system on one of the small commercial vehicle is carried out using multiple virtual simulation tools. Virtual route profile is modelled using longitude, latitude and altitude data captured through GPS and steering duty cycle is mapped in terms of steering rotation angle. A system level model of hydraulic power steering system is developed.

In the modern era of automotive industry, occupant comfort inside the cabin is a basic need and no more a luxury feature. With increase in number of vehicles, the expectations from customers are also changing. One of the major expectations from real world customers is quick cabin cooling thru all seasons, particularly when the vehicle is hot soaked and being used in summer conditions. Occupant thermal comfort inside the vehicle cabin is provisioned by a mobile air conditioning (MAC) system, which operates on a vapor compression-based cycle using a refrigerant. The main components of a direct expansion (DX) based MAC system are, a compressor, condenser, evaporator, and expansion valve. Conditioned air is circulated inside the cabin using a blower, duct system and air vents. The AC condenser is the most critical component in AC circuit as it rejects heat, thereby providing for a cooling effect inside the cabin.

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.

The global and Indian automotive industry is transitioning from use of Internal Combustion Engine (ICE) vehicles towards Battery Electric Vehicles (BEVs). BEV applications with high voltage (HV) battery require optimal thermal management to have a longer life, higher efficiency and to deliver superior year-round performance. In most electric vehicles, the Heating Ventilation and Air Conditioning (HVAC) system operates thru a dual loop; one loop for maintaining desired cabin comfort and a second loop to ensure optimum cell temperature for HV battery operation at varying climatic conditions, which the vehicle experiences over different seasons of the year This paper evaluates the limitations of a baseline system, in which the HVAC system consists of two parallel low-pressure cooling lines, one for maintaining cabin comfort and another for the purpose of battery cooling.

To cope up with the market requirements, OEMs need to react fast and develop advanced and highly refined vehicles keeping in mind multiple factors and Perceived Quality is one of the most important amongst those. Annoying squeak and rattle noises from the vehicle, whether it is new or used car, is the most customer irritant factor; which needs to be addressed in the vehicle development program. BSR (Buzz, Squeak and Rattle) and NVH (Noise, Vibrations and Harshness) performance is the critical in providing quieter experience to the customer and it is becoming more and more important due to transformation from ICE (Internal Combustion Engine) to Hybrid and Electric Powertrains. Among BSR noises, body squeak and creak is the most annoying and difficult to detect and correct, if reported on the prototype test or customer cars. Whereas, squeak and rattles from body fitment and underbody aggregates are relatively easy to address and correct.

This paper is an application of ISO 26262 functional safety standards for fail-safe design, development and validation of Electric Power Assisted Steering (EPAS) System. As part of safety feature to save lives, prevent injuries and reduce economic loss due to accidents, many research institutes are working to ensure the safety and reliability of emerging safety-critical Electronic Control Systems in automobile applications. As, Advanced Driver Assistance Systems (ADAS) and other emerging technologies are introduced in the automobile application, the overall safety of these advanced electronic systems relies on the vehicle safety systems, such as steering systems. This paper outlines the approach of performing the Hazard Analysis & Risk Assessment (HARA) and developing a Functional Safety Concept. This approach incorporates several analysis methods, including Hazard and Operability study, Functional Failure Modes and Effects Analysis.

The small commercial vehicle business is driven by demand in logistic, last mile transportation and white goods market. And to cater these businesses operational and safety needs, they require closed container on vehicle. As of now, very few OEM’s provide regulatory certified container vehicle because of constrains to meet inertia class of the vehicle. This paper focuses on design of a durable and extremely reliable container, made of the low-cost economy class glass fibre & core material. The present work provides the means to design the composite container for the N1 category of the vehicle. The weight of after-market metal container ranges between 300-350 Kg for this category of vehicle, which affects the overall fuel economy and emission of the vehicle. A detailed CAE analysis is done to design composite container suitable to meet inertia class targets and to achieve weight reduction of 30-40% as compared to metal container.

During every clutch engagement energy is dissipated in clutch assembly because of relative slippage of clutch disc w.r.t. flywheel and pressure plate. Energy dissipated in clutch is governed by many design parameters like driveline configuration of the vehicle vis-a-vis vehicle mass, and operational parameters like road conditions, traffic conditions. Clutch burning failure, which is the major failure mode of clutch assembly, is governed by energy dissipation phenomenon during clutch engagement. Clutch undergoes different duty cycles during usage in city traffic, highways or hilly regions during its lifetime. A test schedule was derived using energy dissipated during every clutch engagement event as a base and using road load data collected on the vehicle. Road load data was collected in different road mix conditions comprised of city traffic, highway, hilly region, rough road for few hundred kilometers.

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.

Vehicle aerodynamic design has a critical impact on fuel efficiency of the vehicle. Reducing aerodynamic wind resistance of the vehicle's exterior shape and reducing losses associated with requirements for engine compartment cooling through vehicle front openings plays key role in achieving desired aerodynamic efficiency. Today fairly large number of computational fluid dynamics (CFD) simulations are being performed during the vehicle aerodynamic design and development process and it is rapidly increasing day by day. Vehicle aerodynamic design and development process involves mainly aerodynamic shape development, aerodynamic optimizations of vehicle external components (side view mirror, spoilers, underbody shield etc.) and number of” what if studies during preliminary design process. Licensing costs of the available commercial CFD simulation solver has significant impact on product development cost when numbers of aerodynamic simulations expand.

In the emerging technology trend, there is continuous demand for increase in engine performance in terms of power & torque while providing competitive fuel efficiency. Understanding and fulfillment of complex customer requirements with affordable technology is extremely challenging. In order to meet potential conflicting needs and offer ‘fun to drive’ experience to customers, Tata Motors has developed first in segment turbocharged gasoline MPFI engine. Further in order to create market differentiator, multi drive modes were introduced as segment first feature. The boosted compact 1200 cc engine while developing 90 Ps power, delivers 140 N-m torque over a wide range of 1500-4000 rpm, best suited for Indian drive conditions. This performance boost is nearly 40% over and above performance of comparable NA engine without any compromise on vehicle level fuel efficiency.

Battery cooling system plays a vital role in all kind of Electric vehicles. For Indian applications where vehicles will be subjected to slower speeds due to heavy traffic, higher ambient conditions and excess loading pattern in commercial vehicles, designing a Battery cooling system (BCS) is a challenging task. There are various options for cooling of battery i.e. Natural air cooled, forced air cooled, indirect cooling. This paper discusses about indirect coolant based cooling of battery of a small commercial vehicle. Battery cooling system works on the principle of Indirect cooling with the combination of vapor compression cycle and water-coolant mixture path. R134a gas used for VCRS system and for cooling system used 50-50% water glycol coolant mixture. For this type of battery cooling system typically There are challenges of packaging of various battery cooling parts, hose routing, pipe bends which may result in de aeration issues.

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.

Automotive suspension system forms the basis for the design of vehicle with durability, reliability, dynamics and NVH requirements. The automotive suspension systems are exposed to dynamic and static loads which in turn demands the highest integrity and performance against fatigue based metallic degradation. The current focus in automotive industry is to reduce the weight of the automotive parts and components without compromising with its static and dynamic mechanical properties. This weight reduction imparts fuel efficiency with added advantages. High-Strength Low Alloy steel (HSLA) offers optimum combination of ductility, monotonic and cyclic mechanical properties. Furthermore, welding processes offer design flexibility to achieve robust and lightweight designs with high strength steels.

Environmental regulation, operating cost reduction and meeting stringent safety norms are the predominant challenges for the automotive sector today. Automotive OEMs are facing equally aggressive challenges to meet high fuel efficiency, superior performance, low cost and weight with enhanced durability and reliability. One of the key technologies which enable light weighting and cost optimization is the use of fiber reinforced polymer (FRP) composite in automotive chassis systems. FRP composites have high specific strength, corrosion and fatigue resistance with additional advantage of complex near net shape manufacturing and tailor made properties. These advantages makes FRPs an ideal choice for replacing conventional steel chassis automotive components. However, FRP’s face challenges from operating environment, in particular temperature and moisture.

Regular vehicle has the advantage of Engine resistance even when it is not fired, hence chances of vehicle roll back on gradients will be minimized. This is not the case for Electric vehicles, which uses an electric motor that does not have any resistance offered to wheels that prevent vehicle roll back on gradient. This leads to increased load on the conventional hydraulic brakes due to absence of engine inertia. Hence, there is a need for a low cost and reliable automatic braking system which can help in holding the vehicle and assists the driver during launch in case he need to stop at a gradient. An Electromagnetic brake (EM brake) system can be used as a solution for the above-mentioned requirement. EM brake can provide hill hold and hill assist effect in addition to automatic parking brake application when the vehicle is turned-off. This system will assist anyone who need to halt the vehicle at a gradient and then relaunch it without much struggle.

In the recent years, Hybrid and Electric Vehicles (EVs) have gained attention globally due to conventional non-renewable fuels becoming expensive and increasing pollution levels in the environment. Li-ion battery EV’s are most popular because of their better power density, spe. energy density and thermal stability. With the advent of battery EV’s, concerns regarding thermal safety of vehicle and its occupants has grown among the prospective customers. Temperature plays an important role in the performance of the Li-ion battery which includes cell capacity, charge output, vehicle range, mechanical life of the battery etc. For Li-ion cells, optimum operating range should be between 15-35 °C [1], and all cells must also be maintained within a ±5 °C variation band. Computational Fluid Dynamics (CFD) simulation can be used to get better insight of cell temperature inside battery. But CFD simulation process is complex, time consuming involving multi-physics and exhaustive computations.

A hydraulic-assisted power steering system on a vehicle has a steering pump which is directly driven from the engine continuously. In real world, the assistance from the steering pump is useful only while maneuvering. During a typical highway drive, assistance from this power steering pump remains unused for majority (76%) of the time; although the continuously rotating power steering pump keeps consuming energy from the engine. An electronic controller has been provided for the electro-magnetic pairing device of the power steering pump in order to provide assistance for steering based on driver demand only. The electromagnetic pairing device integrated on the steering pump can be made to engage/disengage based on the driver demand through the electronic controller.

The primary function of an engine mounting bracket is to support the powertrain system in all road conditions without any failure. The mount has to withstand different road conditions and driving maneuvers which exert loads on it. Also, it is challenging to change the mounting locations and types after the engine is built; hence it is paramount to verify the mounting brackets against all abuse loads in the design stage. The Car manufacturers ensure engine mount bracket design meets CAE's (Computer-aided engineering) static and fatigue load cases. The CAE is performed using digital RLD (Road load data) loads. The design checks cumulative strain or stress against specified service life requirements during break and fatigue FOS (Factor of safety) calculations. However, it is difficult to simulate the material's fracture toughness to estimate the effect of the impact load on the mounting bracket.

Powertrain mounts locations and stiffness in vehicle plays very important role in improving vehicle noise and vibration, which is caused by engine firing forces and road disturbances. Once locations are finalized, based on initial calculation and packaging then it is very much critical to play with mount stiffness to achieve required NVH level in vehicle. This paper describes the effect of mount stiffness on the bolted joint integrity. Stiffness fine tuning is done to improve vehicle level NVH and various iteration are done with change in stiffness values of A, B and C mounts. When stiffness specifications are finalized, it is recommended to acquire road load data on the finalized stiffness mount and check for bolted joint integrity since load signature is varying significantly on mount w.r.t stiffness change. If we change mount stiffness value from 128N/mm to 98N/mm, then loads on particular mount is getting increased from 4.5KN to 6.5KN in one of the track testing.