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An agricultural tractor is often modified for special farming applications such as horticulture where the standard design is not suitable or accessible. In such cases, farm equipment manufacturers are demanded frugal and cost effect Engineered farming solutions. One such design is the innovative High Ground Clearance Tractor (HGCT) kit offered to increase the Tractor height without damaging the crop during farming operations. In this paper, the author proposes a durability assessment method to evaluate the HGCT kit attachments to meet the durability criteria. Road load data acquisition is done to measure the acceleration and strain levels for various horticulture operations such as tillage, spraying and transportation. Actual operating conditions are simulated with the help of four poster durability setups inside the lab which helps to reduce the field testing for design iterations.

Tractors primarily serve agricultural functions but are also employed in various other applications such as loading, construction, and hauling. Tractors comprise several key assembly, including the engine, transmission, front hood assembly, and skid, among others. The hood is a critical assembly of the tractor, enclosing the engine and its associated parts. It is constructed from sheet metal with a 'Class A' surface finish for aesthetic purposes. The Hood is locked using latch mechanism mounted on the tractor chassis. The primary function of the hood is to facilitate the opening and closing of the hood assembly during servicing, and it often undergoes rough handling. Therefore, it becomes imperative to validate the durability of the hood assembly to ensure it can withstand the real-world conditions it encounters during these operations.

Tractor is primarily used for Haulage and agricultural applications due to this high tractive effort. A tractor usage has been increased in recent times for its wide range of implement applications. Considering environmental factors and sustainability, restrictions are set on the Tractor emissions. This brings new challenge in the Tractor industry to reduce the carbon footprint. Conventional casting process involves preparation of die & mold, material removal and machining in the final stage to get the desired final product. Alternatively Additive Manufacturing Process (AMP) helps in creation of lighter and stronger parts by adding material layer by layer. By saving the material, weight of the overall Tractor is reduced which helps in reducing carbon footprint. But the disadvantage of this process is the limited availability and high cost of AMP material and lack of infrastructure/skill set for operation handling.

In the realm of modern powertrains, the paramount objectives of weight reduction, cost efficiency, and friction optimization drive innovation. By streamlining drive trains through component minimization, the paper introduces a groundbreaking approach: the integration of fuel pump and vacuum pump drive systems into the main camshaft of a two-valve-per-cylinder push-rod actuated 4-cylinder diesel engine. This innovation is poised to concurrently reduce overall weight, lower costs, and minimize drive losses. The proposed integration entails the extension of the camshaft with a tailored slot, accommodating a three-lobed cam composed of advanced materials. This novel camshaft configuration enables the unified propulsion of the oil pump, vacuum pump, fuel pump, and valve train, effectively consolidating functions and components.

Regenerative braking is an effective approach for electric vehicles (EVs) to extend their driving range. To enhance the braking performances and regenerative energy, regenerative braking control strategy based on multi objective optimization is explained in this paper. This technical paper would be focusing on extracting optimum Range with effective brake performances without affecting drivability and performances in different drives modes. An extensive research study on public road driving patterns is done to understand the percentage utilization of brakes at various (low-mid-high) speeds as per the customer driving behavior. Multi-Objective optimization function with three vital factors is defined where output generated power, torque smoothness and current smoothness are selected as optimization objective to improve the driving range, braking comfort, and battery lifetime respectively.

Construction equipment off highway vehicles are heavy industry vehicles that run on diesel engines. To meet the emission norms, these engines have the Exhaust After Treatment System (EATS) which includes two primary subassemblies, i.e., a Diesel Oxidation Catalyst (DOC) subassembly to reduce the HC and CO emissions and a Selective catalytic Reduction (SCR) subassembly to reduce NOx emissions. Because of the excessive vibrations in the engine and continuous heavy-duty usage of the Construction equipment, any failures in the EATS system leading to escape of exhaust gas is a statuary non-compliance. Hence, understanding the effect of engine vibrations and proposing a cost-effective solution is paramount in designing the EATS system including the SCR assembly. A field-testing failure of an SCR assembly has been taken in consideration for this study.

In automotive market, with competitive car prices, build quality of a car will be a major distinguishing factor. Consumer's need for acoustic comfort has evolved from the removal of annoying noises to perceived sound quality. Operational sounds from electromechanical systems like sunroof system, window regulator, door lock system, HVAC etc. directly interact with users’ senses. The perceived acoustics comfort of these sounds are direct indicators of vehicle character and can influence customer’s buying decision. With the reduction in product development time and stringent cost constraints, a proper structured target setting methodology to benchmark & evaluate these operational sounds is crucial. In this paper, such a target setting methodology is proposed and discussed for operational sound quality evaluation. Electromechanical noises from various vehicles are measured using binaural head measurement system.

Usually conventional iterative methods of optimization will consume more time to optimize the given design. Mostly, it becomes very difficult if multiple loads are acting on the structure contradicting each other. CAE based optimization technique becomes more useful in such cases to optimize the given design and achieve weight reduction. Optimization methods offers guidance to expedite solutions, resulting in a substantial reduction in product development time. Nowadays, optimization became inevitable part among the virtual validation processes of design in industries. A wide range of optimization methods have been effectively employed in the design of tractor components, especially mounting brackets, chassis and skid housing for the development of off-road vehicle. Based on the design stage, various optimization techniques were followed i.e. Topology, size and shape. Depending upon the available analysis time & Design freedom, determines the type of optimization approach to be used.

The inherent capacity of electric motors to generate substantial instant torque can lead to significant load reversals in electric vehicle driveshafts under specific road conditions and driving maneuvers, highlighting the need for targeted improvements in driveshaft design, particularly in optimizing joint sizing. This paper presents a systematic approach to investigate the root causes of a catastrophic driveshaft failure that occurred during specific vehicle tests on a road with multiple speed bumps, resulting in numerous high torque reversals. The objective was to enhance system robustness through changes in driveshaft design and the manufacturing process, coupled with a software calibration technique to reduce torque demands under such operating conditions. The process encompassed torque measurements at the vehicle level, failure replication on a test rig, and correlation with simulations.

The commercial vehicles market is dominated by manual transmission, due to lower ownership cost. Generally, commercial vehicles are used in large numbers by the fleet owners. The transmission endurance life is very important to a vehicle owner. On the other hand, driver fatigue can be reduced with a smooth gear change process. The gear change process in a manual transmission is carried out with the help of the synchronizer pack. The crucial function of a synchronizer pack in an automotive transmission is to match the speed of the target gear for smooth gear shifting. In a transmission, the loose and the weakest part is the synchronizer ring. The failure of the synchronizer affects smooth gear shifting and it also affects the endurance life of the transmission. The synchronizer ring can fail due to poor structural strength, synchronizer liner wear, synchronizer liner burning, etc.

In the current automobile era, weight, emission, and fuel efficiency were driving the overall powertrain development without compromising on the performance. Due to light weight and high-performance engines, the increased level of excitations in terms of torsional, axial, and bending frequency on crank shaft during combustion is inevitable. The axial and bending moment exerted from crankshaft during combustion causes vibration of the clutch diaphragm spring, in turn these vibrations are transferred through the hydraulic release system to clutch pedal which induces undesirable pedal pulsation and vibration during clutch pedal operation. The subjective perception on Noise Vibration and Harshness (NVH) becomes more essential in the Vehicle development process of modern high-performance vehicles.

With the advent of stricter emission norms such as Bharat Stage VI - Phase I and II, the design of the exhaust after treatment system becomes crucial for the internal combustion engine. Inadvertently, the size of the after-treatment system also becomes bigger to cater to the latest emission norms, which leads to increased resistance to the flow of exhaust gases through them. However, the resultant back pressure generated in these devices deteriorates the engine performance. Hence, the onus is on the engine designer to design the after-treatment system and the bracketing concept for mounting in such a way that the engine performance remains intact, and the entire system is packaged within the vehicle boundary conditions. The after-treatment system experiences severe vibrational loads as well as thermal loads.

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.

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.

AC system provides the human comfort inside the cabin of a vehicle but at the expense of consumption of energy from the vehicle. On a global perspective for the bus segment, there is an increased demand for cooling in tropical countries. Optimization needs to be done in existing AC systems w.r.t packaging, cost & performance constraints. Major elements contributing to heat ingress are engine hood, front firewall, windshield & side glasses and bus body parts. Due to these reasons inadequate passenger comfort and poor cool down performance of the vehicle is observed. This paper refers to the reduction of heat ingress through different DOE (Design of Experiment) in the area of design & validation for duct & vent layout, insulation, glass & paint technology, evaporator blowers. The new duct design has been evaluated using a CFD tool by varying various parameters to generate desired output. The integrated use of the modifications was found significant improvement at vehicle level.

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.

Twist-beam suspensions are an example of design solution presenting acceptable performance when applied to passenger cars & light vehicles and it can provide an optimal between cost & performance in the automotive market. For these reasons, twist beam is quite popular in use in rear suspension of light vehicles. In contrary to other types of suspension, the twist-beam has a flexible torsion beam connecting the swing arms. The study of the deformation of this flexible element becomes important to understand its performance and durability behavior. As the name signifies, twist beam major performance attribute is control of twist or opposite wheel travel arising from vehicle roll or road input. Current approach for the study this deformation is through FEA & Multi-body dynamics software tools.

Vehicles subjected to Indian duty cycles have to undergo extreme environments & road terrains, stone chipping. Underbody wear from this is one of the most significant forms of deleterious corrosion. Automobile companies deal with this by going for exotic & expensive underbody coating, which compositionally are "Polyvinyl Plastisol also popularly known as Poly Vinyl Chloride (PVC)". Across automotive industry, the stone chipping is prevented via applying PVC-coating to the extent of 800-1000 microns. The application of PVC-material throughout the vehicle underbody will add approximately 8-12 Kgs of weight. Our objective was to reduce the weight of applied PVC-material.

Design of HVAC system plays an important role in acoustic comfort for passengers. With automotive world moving towards electrical vehicles where powertrain noise is low, designing low noise HVAC system is becoming more important. For an automobile manufacturer, ability to predict the production vehicle cabin noise at the early design stage is important as it allows more freedom for design changes, which can be incorporated in the vehicle at lower cost. Although HVAC prototype and system level testing at early design stage is possible for noise estimation but flow field is not visible in test that makes difficult to improve design. CFD simulation can provide detailed information on flow field, noise source strength and location. But in such a simulation, accurate prediction has been a challenge due to the inability of CFD tools to model acoustic absorptive characteristics of interior walls of cabin.

This paper takes a review of fretting phenomenon on splines of the engaging gears and corresponding splines on shaft of automotive transmission and how it leads to failure of other components in the gearbox. Fretting is a special wear process which occurs at the contact area of two mating metal surfaces when subject to minute relative oscillating motion under vibration. In automotive gearbox, which is subjected to torsional vibrations of the powertrain, the splines of engaging gears and corresponding shaft may experience fretting, especially when the subject gear pair is not engaged. The wear debris formed under fretting process when oxidizes becomes very hard and more abrasive than base metal. These oxidized wear particles when comes in mesh contact with nearby components like bearings, gears etc. may damage these parts during operation and eventually lead to failure.