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The bolted joints in suspension systems are subjected to severe external service loads during vehicle operation. To prevent the loaded joint from loosening and allowing it to retain its potential energy stored during assembly, a holistic design approach is needed. This paper explains the methodology to design and optimize bolted joints for the suspension systems of a modern 7-seater sports utility vehicle.

Foundry industries are very much familiar and rich experience of producing ferrous castings mainly Flake Graphite (FG) and Spheroidal Graphite (SG) cast iron. Grey cast iron material is mainly used for dampening applications and spheroidal graphite cast iron is used in structural applications wherein high strength and moderate ductility is necessary to meet the functional requirements. However, both types of cast iron grades are very much suitable in terms of manufacturing in an economical way. Those grades are commercially available and being consumed in various industries like automotive, agriculture etc, High strength SG Iron grades also being manufactured by modifying the alloying elements with copper, chromium, manganese andcobalt. but it has its own limitation of reduction in elongation when moving from low to high strength SG iron material. To overcome this limitation a new cast iron developed by modifying the chemical composition.

Original Equipment Manufacturers (OEMs) should innovate ways to delight customers by creating affordable products with improved drive experience and occupant comfort. Vehicle refinement is an important initiative that is often take-up by the project teams to ensure that the product meets the customer’s expectations. A few important aspects of vehicle refinement include improving the Noise Vibration Harshness (NVH), ride and handling performance pertaining to the Functional Image (FI) of the product. Optimizing the suspension design variables to meet both ride and handling performance is often challenging as improving the ride will have a deteriorating effect on handling and vice-versa. The present work involves Multi-Objective Design Optimization (MDO) of the suspension system of an automotive Sports Utility Vehicle (SUV) platform considering both ride and handling requirements, simultaneously.

As a car OEM, we continuously strive to set the bar for competitors with every product. Consumer travel experiences are enhanced by increasing passenger cabin silence. There is only one steering system opening in the firewall panel, which is used for allowing intermediate shaft's fitment on the pinion shaft of the steering gear. The steering grommet is the sole component that covers the firewall cut-out without disrupting steering operations, which has a substantial impact on the NVH performance of the vehicle. It is typically used in cars to eliminate engine noise and dust entering to passenger compartment. The part is assembled inside the vehicle where the steering intermediate shaft passing through BIW firewall panel. We use a bearing, plastic bush, or direct rubber interference design in the steering grommet to accommodate the rotational input the driver provides to turn the automobile.

The maximum power produced by the Engine is utilized in overcoming the Aerodynamic resistance while the remaining has been used to overcome rolling and climbing resistance. Increasing emission and performance demands paves way for advanced technologies to improve fuel efficiency. One such way of increasing the fuel efficiency is to reduce the aerodynamic drag of the vehicle. Buses emerged as the common choice of transport for people in India. By improving the aerodynamic drag of the Buses, the diesel consumption of a vehicle can be reduced by nearly about 10% without any upgradation of the existing engine. Though 60 to 70 % of pressure loads act on the frontal surface area of the buses, the most common techniques of reducing the drag in buses includes streamlining of the surfaces, minimizing underbody losses, reduced frontal area, pressure difference between the front & rear area and minimizing of flow separation & wake regions.

A hydraulic power train assembly of an agricultural tractor is meant to lift the heavy implements during field operations and transportation. As it is a crucial member of the tractor for its usage, so the power train assembly needs a properly designed lift arm, rocker arm assembly with better strength and stiffness. There are a standard like IS12224, IS4468 which regulates the test method for hydraulic power and lift capacity of tractor and the layout of hydraulic three point linkage. Computer aided engineering techniques followed by laboratory testing have been deployed in the earlier stages of the product design & development itself to deliver the first time right products to the customer. In this paper, a virtual simulation process has been established to design an agricultural tractor hydraulic lift arm to meet the above requirements. A Design Verification Plan (DVP) has been developed consisting of 3 load cases.

The input shafts are conventionally developed through Hot forging route. Considering upcoming new technologies the same part was developed through cold forging route which resulting in better Mechanical properties than existing hot forging process. It has added benefit of cost as well as environmental friendly. Generally, the part like Input shaft which having gear teeth, splines etc., will be manufactured through Hot forging process due to degree of deformation, availability of press capacity, diameter variations etc., This process consumes more energy in terms of electricity for heating the bar and also creates pollution to the atmosphere. Automotive input shaft design modified to accommodate cold forging process route to develop the shaft with press capacity of 2500T which gives considerable benefit in terms of mechanical and metallurgical Properties, close dimensional tolerances, less machining time, higher material yield when compared to hot forging and metal cutting operation.

The Indian automotive industry has migrated from BS IV (Bharat stage IV) to BS VI (Bharat Stage VI) emission norms from 1st April 2020. This two-step migration of the emission regulations from BS IV to BS VI demands significant engineering efforts to design and integrate highly complex exhaust after-treatment system (EATS). In the present work, the methodology used to evaluate the EATS of a high power-density 1.5-liter diesel engine is discussed in detail. The EATS assembly of the engine consists of a diesel oxidation catalyst (DOC), a diesel particulate filter with selective catalytic reduction coating (sDPF), urea dosing module and urea mixer. Typically, all these components that are needed for emission control are integrated into a single canning of shell thickness ~1.5mm. Moreover, the complete EATS is directly mounted onto the engine with suitable mounting brackets on the cylinder block and cylinder head.

The excitation to a vehicle is from two sources, road excitation and powertrain excitation. Vehicle Suspension is designed to isolate the road excitation coming to passenger cabin. Powertrain mounts play a vital role in isolating the engine excitation. The current study focuses on developing an analytical approach using Low-Fidelity computer programs to design the Powertrain Mount layout and stiffness during the initial stage of product development. Three programs have been developed as a part of this study that satisfy the packaging needs, NVH requirements and static load bearing requirements. The applications are capable of providing the Kinetic Energy Distribution and Static Analysis (Powertrain Enveloping and Mount Durability) for 3-point and 4-point mounting systems and the ideal mount positions and stiffness for 3-point mounting systems.

This paper deals with an analytical method to calculate the press-fit tolerance and fits between gears and shaft for automotive applications. The relative interferences increase sharply in the small diameter range, therefore one must be especially careful when designing small diameter joints. The strength of press-fit depends on the amount of relative interference; extreme interference leads to excessive contact stresses between the gear and shaft eventually leading to failure. Too little interference leads to slippage of gear on the shaft. In the press fit connection a shaft's spline rolling operation and gear internal broaching is eliminated. It is more economical than a conventional spline connection. Press fit connections are used in various transmission between a shaft and a gear. They are used in 6 speed transmission to 9-speed transmission for (German based Vehicle Manufacturer) heavy and light commercial vehicle company.

Vibrational fatigue is a metal fatigue caused by the forced vibrations which are purely random in nature. The phenomenon is predominantly important for the components/systems which are subjected to extreme vibration during its operation. In a vehicle, an engine is the main source of vibration. The vibrational fatigue, therefore, plays a key role in the deterioration of engine mounted components. Multiple test standards and methodologies are available for validating engine mounted parts of an automobile. These might not be appropriate in the case of an off- road vehicle as the vibrational exposure of engine mounted components of an off-road vehicle is entirely different. In the case of an off-road vehicle, the engine mounted components are subjected to a comparatively higher level of vibration for a longer duration of time as compared to the passenger cars.

The emission norms around the world are continuously changing and getting stringent with every revision. India is on its way to make its emission norms at par with that prevailing in the developed nations. The cold-start condition is an important factor affecting vehicle emissions from gasoline direct injection (GDI) and port fuel injection (PFI) vehicles. In this paper, the effects of change in torque converter losses on emissions are experimentally investigated in a TGDI AT vehicle. The instant engagement of the torque converter puts a sudden load on the engine and thus affects its stability. Thus, to overcome the stability issue, Engine Torque has to be simultaneously increased for smooth engagement. As a result, the likelihood of the slightly leaner air-fuel mixture in the cylinder, which results in higher NOx formation, is much greater in an AT vehicle than that of a similar MT vehicle.

Lubrication system is a critical factor for engine health. But it creates parasitic load and increased fuel consumption of the engine. The oil demand of an engine depends on engine speed, load, bearing clearances, operating temperature and engine's state of wear. Ideally, the oil pump should adapt the delivery volume flow to actual engine oil demand and should avoid unnecessary pumping of oil which causes increased power and fuel consumption. However in a conventional mechanical oil pump, there is no control on the oil flow and it is purely a function of operating speed. A variable discharge oil pump (VDOP) is an approach to reduce the parasitic losses wherein the oil flow is regulated based on the mechanical needs of the engine. This study is based on the results of a two stage VDOP installed on a 1.2 litre, 3 cylinder MPFI engine. The oil supply is regulated by a solenoid control which receives command from Engine Control Unit (ECU). The study was done in two stages.

This paper presents the analysis and experimental validation of c-spring and its stiffness properties in the gear shift synchronizer system. A synchronizer assembly for a transmission comprises of a synchronizer hub carried by a torque delivery shaft and a cone clutch member carried by a gear and a synchronizer blocking ring. The gear shift sleeve is meshing over the teeth of the clutch hub. The c-spring is positioned in the inner circumference of the rim position of the clutch hub and strut keys will be positioned at the slots on the clutch hub, which are usually 120 degree apart. As the sleeve moves while gear shifting, it pushes down the strut keys which compress the C-spring radially inward; this gives the strut load. The strut keys, which are pushed down by the sleeve, will apply force on the c-spring from radial directions. Since the c-spring is in the shape of an arc it is assumed as a curved beam for the analysis.

To comply with the stringent future emission mandates of light-duty diesel engines, it is essential to deploy a suitable combination of emission control devices like diesel oxidation catalyst (DOC), diesel particulate filter (DPF) and DeNOx converter (LNT or SCR). Arriving at optimum size and layout of these emission control devices for a particular engine through experiments is both time and cost-intensive. Thus, it becomes important to develop suitable well-tuned simulation models that can be helpful to optimize individual emission control devices as well as arrive at an optimal layout for achieving higher conversion efficiency at a minimal cost. Towards this objective, the present work intends to develop a one-dimensional Exhaust After Treatment Devices (EATD) model using a commercial code. The model parameters are fine-tuned based on experimental data. The EATD model is then validated with experiment data that are not used for tuning the model.

Plastics are prone to photo oxidative and thermal oxidative degradation under usage conditions due to their chemical nature. From sustainability and cost standpoint, there is an increasing focus on Mold-In-Color (MIC) plastic materials. Simultaneously customer’s expectations on the perceived quality of these MIC parts has been increasing with attractive color and glossy appearance. A study was conducted to analyze the product quality and durability aspects over a prolonged exposure to accelerated weathering condition. Material selected for this study were injection molded specimens of ABS and PC-ABS used in automotive passenger vehicles. Comparative analysis was conducted before and after weathering exposure at defined intervals by using Fourier Transform infra-red spectrometer (FTIR), differential scanning colorimetry (DSC), universal testing machine (UTM), Izod impact tester and microscope to understand the impact on their chemical and mechanical properties.

One of the major challenges for automotive industry today is to reduce tailpipe emission without compromising on fuel economy especially with the EURO 6, RDE, LEV III emissions and CO2 norms coming up. In case of diesel engines, with the emission norms becoming stringent more and more, it's difficult to improve tradeoff between NOx and PM emissions. After treatment systems give some edge in terms of tail pipe emission reduction but not on the cost, fuel economy and system simplicity front. For diesel engines the compression ratio and design of the bowl geometry plays a crucial role in controlling emission and CO2. The target was to achieve EURO 6 tailpipe emissions with minimum dependency on after treatment. With the target after treatment conversion efficiency the engine out targets were framed. A study of different bowl geometries were made that would help achieve this target of improving reduced engine out emissions.

India's high Air Pollution level is the focus of discussions as we grow. Plans to combat this menace and implement the latest Technologies are gathering pace. The increasingly stringent emission legislations provide a continuous challenge for the non-road market. Tractor manufacturers are evaluating the need for cost-effective technology to meet upcoming stringent emissions targets. Simply following global approach may not work for Indian market considering the customer usage pattern & perceptions. With an anticipation of upcoming emission norms being based on US-EPA TIER-4 final up to 75 Hp, major technology up gradation is expected for farm equipment sold in India. The enormous diversification of engines within the different power classes as well as the operation specific requirements regarding various duty cycles, robustness and durability, requires specific solutions to meet these legal limits.

The SAE J1100 based standard cargo volume index methods and predefined luggage objects are very specific to United States population. The European luggage volume calculation and standard luggage calculations are primarily based on DIN and ISO standards. Luggage volume declaration by manufacturers are based on any of these methods. The calculations are complicated and there is a possibility of declaring different values for similar luggage compartments. The major purchase decision of vehicle is based on its luggage capacity and current methods are very limited to make an intelligent decision by a customer. Market specific customer usage patterns for luggage requirements and protecting them in vehicle architecture upfront in concept stage is important to retain the market position and buying preference of customers. The usage patterns is collected from customer clinics and marketing inputs.

Powertrain complexity rapidly increasing to meet fast moving regulation requirements. The BS6 Phase-1 regulation norms were implemented in India from April 1, 2020 and replaced the previous BS4 norms. Phase-2 of the BS6 regulation norms were came into effect on April 1, 2023. To meet this stringent regulation requirement, need effective performance of after treatment systems like DOC, DPF and SCR demands critical hardware selection and implementation. In Indian market, LCV application is cost sensitive and highly competitive where operational cost is most critical factor. Naturally aspirated engine has less operating cost, which is the best for LCV applications, but is has its own challenges to meet BS6 norms like higher engine out NOx, dynamic temperature profiles etc. A robust DeNOx emissions strategy is developed in naturally aspirated engine LCV application to meet cycle emissions, real drive emissions and OBD requirements.