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The entire commercial vehicle industry is moving towards weight reduction to leverage on the latest materials available to benefit in payload & fuel efficiency. General practice of weight reduction using high strength steel with reduced thickness in reference to Roark’s formula does not consider the stiffness & dent performance. While this helps to meet the targeted weight reduction keeping the stress levels within the acceptable limit, but with a penalty on stiffness & dent performance. The parameters of stiffener like thickness, section & pitching are very important while considering the Stiffness, bucking & dent performance of a dumper body. The Finite Element Model of subject dumper body has been studied in general particularly on impact of dent performance and is correlated with road load data to provide unique solution to the product. The impact of payload during loading of dumper is the major load case.

The usage of forging a preformed, near net shape, compacted and sintered metal powder has been widely accepted since the eighties and is now one of the mainstays for producing Connecting rods in North America. However, its use in Indian subcontinent is limited as its counterpart i.e. conventional steel forging is still the most dominant. Powder metallurgy route has many advantages like good dimensional accuracy; minimum scattering of weight etc. Despite these advantages, the Powder metallurgy process is still not preferred predominantly due to technical (endurance) and infrastructural limitations. This work envisages combining the benefits of powder metallurgy process with the required mechanical properties viz. tensile and fatigue strength alongside design modifications to meet the requirements of a connecting rod for a 2-cylinder diesel engine. The connecting rods met the fatigue life at the required FOS equaling the performance of a conventionally forged connecting rod.

In today’s manual transmissions of car, gearshift system requires high performance with particular emphasis on low effort, minimal travel and positive feel. To meet these targets, a high capacity multi cone synchronizers along with higher co-efficient of friction material used for lower gears. The design of synchronizer with these specifications is influenced by torsional fluctuations from engine. Excessive torsional vibrations leads to wobbling of synchro rings within the peripheral clearances with surrounding parts. Wobbling leads to abrasion wear of frictional area of synchro ring causing grating or crashing noise of gears during shifting. This paper presents the optimization of the multiple cone synchronizer design exposed to excessive torsional vibrations and validation of the same on test bench during development stage instead vehicle level validation.

In case of new generation of commercial vehicles, three shaft transmissions are designed with press fitted gears on counter shaft. It allows user to save the cost of transmission manufacturing by considerable amount. In case of heavy commercial vehicles, which are being used in abusive conditions such as mining and off-road applications, it becomes absolutely necessary to ensure that the gears press fit should withstand the continuous loads and impact loads. There are design guidelines available to ensure proper fit and torque carrying capacity between the mating parts. Still, there are gear slippage, shaft and gear breakage failures in the field. In this scenario, there is a need to develop bench test procedure which will capture such failures in the prototype stage. Looking at the failures in the field, it is necessary to capture all above hidden failures in design validation phase.

The changing mobility landscape of India reveals that the erstwhile transport modes of the 20th century i.e., railways and road buses are making way for airlines, personal vehicles, shared mobility, metro rails. Rapid technological changes, stricter regulations, new transport cultures autonomous, connected, electric and shared (ACES), state-of-the-art and environmental concerns are shaping up the eco-system for automobiles. Despite these challenges roadways and automobiles will continue to be most prominent solution in India for future. But for that, the automobile sector should be agile, innovative, and adaptable to changing eco-system, vigilant to thwart threat of alternate mobility solutions and must provide sustainable solutions for the future. The purpose of this paper to evaluate various mobility solutions, ascertain prominence of upcoming automobile solutions and their sustainability for future in India.

Electric motor mounts resonate at high frequency in the range of 600 to 1000Hz with motor excitation frequency resulting in isolation performance deterioration. There is a selection process of motor mounts such that the force-transfer under transient torque reduced and also avoids high-frequency resonance. The rubber dynamic stiffness plays a significant role in excitation frequency. Rubber shape factor and compound directly contribute towards the dynamic stiffness properties of the mount. Isolation efficiency depends on force transfer to the body and resonance phenomenon. In this paper, the rubber shape of motor mounts, which affect progression characteristics as well as high-frequency resonance, is discussed. The wings-effect of rubber bushes discussed which can be tuned to get the desired frequency shift in order to avoid resonance.

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.

State of Charge (SoC) estimation of battery plays a key role in strategizing the power distribution across the vehicle in Battery Management System. In this paper, a model for SoC estimation using Extended Kalman Filter (EKF) is developed in Simulink. This model uses a 2nd order Resistance-Capacitance (2RC) Equivalent Circuit Model (ECM) of Lithium Ferrous Phosphate (LFP) cell to simulate the cell behaviour. This cell model was developed using the Simscape library in Simulink. The parameter identification experiments were performed on a new and a used LFP cell respectively, to identify two sets of parameters of ECM. The cell model parameters were identified for the range of 0% to 100% SoC at a constant temperature and it was observed that they vary as a function of SoC. Hence, variable resistance and capacitance blocks are used in the cell model so that the cell parameters can vary as a function of SoC.

In the recent years steering feel characteristics have emerged as one of the important brand image attributes of automotive OEMs. Since past few decades, the hydraulic assisted steering system (HPAS) on which lot of research was done to tune the steering feel has been taken over by electric power assisted steering (EPAS) system. The EPAS primarily uses an electric motor controlled by an electronic control unit to assist the driver in maneuvering the vehicle. The next big leap in the steering system advancement is steer-by-wire (SbW) technology where the mechanical linkage between the steering wheel and the road wheels is eliminated. The advantages of this system are ease to use, elimination of noise-vibration-harshness of steering system caused by road forces, modularly of steering system for packaging, improved visibility to front-end displays and road ahead and a fun to drive concept.

Engine performance and emission control are key attributes in the overall engine development in which sealing of the mating components plays an important role to achieve the same. Rubber gaskets are being used for sealing of different Internal Combustion (IC) engine components. Gasket sealing performance needs to be ensured at initial development stage to avoid the design changes at the later part of development cycle. Design changes at later stage of development can potentially influence parameters like optimization, cost and time to market. Demand of utilization of virtual tools (front loading) is growing with the increasing challenges like stringent product development cycle time and overall project cost. This paper describes a procedure to simulate the rubber gasket and groove for different material conditions (dimensional tolerances). This entire simulation is divided into two phases. In the first phase of the simulation, Load Deflection curve (LD curve) is established.

The authors of this technical paper conceptualize and illustrate a powertrain architecture for a hybrid electric vehicle coupled with a unique strategy to reduce a real life problem of driving in snail paced traffic. This architecture utilizes a relatively low powered hybrid electric prime mover that is generally used in mild hybrid vehicles, in an arrangement similar to a parallel hybrid system. Here, the electric machine is mounted on the input shaft of the gearbox and the clutch is actuated automatically through an Automated Manual Transmission (AMT) system. Therefore, it is possible to completely disengage the engine from the driveline and drive the vehicle independently through an appropriately sized electric prime mover. The high gear ratio between the drivetrain and the electric prime mover at lower gears can be leveraged to provide low velocity electric creep mode during which the vehicle can function as a pure Electric Vehicle (EV) while engine remains off.

Structural automotive components are subjected to fatigue damage under cyclic stresses and strains. The fatigue damage initiates at stress levels lower than the elastic limit of the material and results in cracks. The Initial fatigue cracks are difficult to detect, such cracks can develop rapidly and cause sudden and brittle failure in structures. Many structural automotive components are fabricated involving weld induced local conditions such as geometry of weld toe and localized tensile residual stresses. These conditions are favorable for initiation of fatigue damage at weld toe. In current work, sever plastic deformation (SPD) which is based on high frequency impact treatment using ultrasound energy was applied on weld toe of representative weld joints. The effect of SPD on weld toe geometry modification, microstructure and residual stresses were evaluated. Microscopic and X-ray diffraction techniques were used to study the effects of SPD.

Rising environmental concerns and depleting natural resources have resulted in faster adoption of green technologies. These technologies are pushed by the government of states through certain schemes and policies as to make the orbit shift ensuring greener environment in near future. Major actions can be easily seen in transportation sector. Hybrid Electric Vehicle (EV), EV and Fuel cell EV are being deployed on roads rapidly but even though some challenges are still unsolved such as battery cost, fast charging and life cycle of the automotive battery. Automotive batteries (Lithium ions) are declared as unfit for automotive usage after the loss of 20% to 15% of their initial capacity. Still 80% to 85% of battery capacity can be utilized in stationary applications other than automotive. Stationary application doesn’t demand high current density or energy density from the battery pack as of automotive requirements.

New generation light commercial vehicles are expected to have lower steering effort, high self centering and less turning circle diameter covering large variety of wheelbases from 2.8 m to 4.5 m even with mechanical steering and keeping same number of total turns of steering wheel compared to old generation light commercial vehicles. To address above requirements, below parameters related to steering and rigid front axle were studied. 1 Caster angle of front axle 2 Steering compliance and Steering ball joint articulation angle 3 Front axle kingpin axial play 4 Steering gearbox ratio 5 Pitman arm length The effect of above parameters was studied in isolation and combination. This optimization has resulted in least steering effort and least turning circle diameter in light commercial vehicles with mechanical steering and option of power steering could be eliminated for cost reduction.

Noise Vibration and Harshness (NVH) refinement is one of the important parameters in modern vehicle development. In city traffic conditions, idling is an engine operating condition where a driver focuses attention more to his/her vehicle. Tactile vibration & noise levels inside the cab play an important role in all vehicles, especially those powered by diesel engines where combustion pressures are higher. They lead to discomfort & fatigue of passengers of even a low cost vehicle. Now its idle NVH is influenced mainly by vibration-isolation provided by power-train (PT) mounting design, This paper describes steps taken to improve the idle vibrations at a driver seat of a small commercial vehicle (SCV) with a 2-cylinder diesel engine of 800 cc through redesign of PT-mounting along with fine tuning of idle speed of the engine. A resonance was avoided between the first firing order at idling and PT rigid-body mode in pitching.

For sustainability in automobile manufacturing, recycle, reuse, and repair of used up cutting tools is now an established process. Although many types of tools were designed for one time use and then throw, an increasing awareness of the impact on the natural resources have made manufacturers to put some of these back to use or sell it back to suppliers who have put up a mechanism to extract the elements e.g. Tungsten and use it for manufacturing of new tools. There are many ways in which cutting tools can be recycled. Be it by reshaping a used up throwaway type tool [1], by redesigning of a tool holder for the use of unused cutting edges [2] or reusing short length drills that are used in making of long oil holes in crank case, cylinder head, cam shaft or connecting rods [3]. This paper demonstrates successful use of used up crankshaft grinding wheels.

A large number of metal cutting inserts are used in the manufacturing of automobile parts. These are made from hard metals like Carbide, Ceramic, Cermet, PCD and CBN. Since making of these hard metal inserts involve a high amount of energy in addition to natural resources namely Titanium, Tungsten, Cobalt etc, any attempt made therefore for reusing of the used up inserts will benefit environment because this reuse will lower down the demand on natural resource. Reuse can be done in a number of ways [ 1 ]. Many of these recycling techniques involve removing the dull portion developed during the first use by re sharpening [ 2 ]. A different approach is being suggested here in which used up inserts can be used directly. This approach leads to use of the unused cutting edges /corners of the insert without any re sharpening. Thus the cost of machining becomes half of the original cost or even more depending on the application for reuse.

Vehicle crashworthiness is an important aspect of vehicle development. Vehicle structural performance plays a critical role during crash for controlling the occupant injuries. During a crash event, vehicle energy management governs the structural performance and passenger compartment integrity. However, these parameters are dependent on material properties such as yield/ultimate tensile strength, work hardening effects, strain rate dependency, material elongations and material fracture strains. Appropriate representation of these material properties in CAE (Computer Aided Engineering) environment is very critical for reliable prediction of vehicle structural performance during development phase. Among all material properties, material fracture strain is the most complex one and needs detailed material characterization approach for failure definitions.

Due to the recent trend in auto industry to opt for higher power engines, causes increase in vibrations levels in the passenger’s compartment. This requires a better and comprehensive model to analyze vibrations from engine to seat and steering wheel much before the proto stage of development in the design stage itself. For this purpose, modelling is done in ADAMS multi dynamics and assuming the 16 degrees of freedom of the vehicle. Further, a crank drive model is developed to simulate engine excitation forces comprising unbalanced inertia forces and torque fluctuations and their effects seat rail and steering wheel vibration is derived. This tool is an attempt to predict such vibrations caused and assist in design enhancement and streamline the procedure.

Comfortable cabin environment from temperature, noise and vibration point of view is one of the most desirable aspects of any vehicle operating in hot or cold environment. Noise generated from HVAC system is one of the most irritating phenomena resulting in customer dissatisfaction and complaints. It becomes absolutely necessary to have low HVAC noise levels when the target market has hot weather all round the year. Balance between control of temperature in desired way with least possible noise and vibration is the key for HVAC performance optimization within constrains posed by design and cost. This paper describes the approach for NVH refinement of front HVAC system proposed for a vehicle with limited off-road capability for which packaging constraints and late changes related to airflow and HVAC unit design for meeting comfort and crash requirements resulted in deterioration of noise and vibrations while operation.