Search Results

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.

For ensuring environmental safety, strong emphasis on CO2 pollution reduction is mandated which led to evolution of miller cycle engines. However, the inherent Miller engine characteristic is the lower volumetric efficiency when compared to otto engines because of which small turbo chargers with variable geometry turbines are used to induct air into the engine. With miller engine and VGT turbo charger combination arises the challenges of charge controllability because of lower inertia and reduced vane control area. With conventional turbo charger control methods, the response time is slow thereby leading to turbo lag or severe over boosting, this is overcome by accurate engine modelling and using the same as input for charger control.

Closed crankcase ventilation prevent harmful gases from entering atmosphere thereby reducing hydrocarbon emissions. Ventilation system usually carries blowby gases along with oil mist generated from Engine to Air intake system. Major sources of blowby occurs from leak in combustion chamber through piston rings, leakage from turbocharger shafts & leakage from valve guides. Oil mist carried by these blowby gases gets separated using separation media before passing to Air Intake. Fleece separation media has high separation efficiency with lower pressure loss for oil aerosol particles having size above 10 microns. However, efficiency of fleece media drops drastically if size of aerosol particles are below 10 microns. Aerosol mist of lower particle size (>10 microns) generally forms due to flash boiling on piston under crown area and from shafts of turbo charger due to high speeds combined with elevated temperatures. High power density diesel engine is taken for our study.

In automotive world role of suspension system is to absorb vibrations from the road, and to provide stability while vehicle is going over bumps or uneven roads, cornering, acceleration and braking etc. For body on frame SUVs which are typically characterized by high center of gravity, it is quite critical to find best balance in ensuring stability of the vehicle and having comfortable ride performance. Rigid axle rear suspension is quite a typical choice in such vehicles, wherein lower and upper control links are two important components subjected to lateral, longitudinal, and vertical loads. These links allow the vehicle to move smoothly throughout the entire range of suspension travel. Kinematics and compliance optimization of these links is a major factor in definition of ride-handling performance of the vehicle.

Increased popularity on SUV category in the market has led to high focus on performance attributes of SUVs. Considering high weight & CoG achieving target handling performance is always a challenge. Static Wheel Alignment parameters, especially Camber have shown significant contribution in Handling attributes of vehicle. This paper presents an experimental study on change in wheel camber under the influence of different vehicle loading conditions. In SUVs, generally wheel is subjected to large deflection from its high static loads which makes it quite difficult to maintain an ideal camber angle. Hence, it is important to analyze the camber angle variations under actual loading conditions. An in-house fixture is developed to emulate the actual vehicle loading conditions at rear wheel end. The multi-link rigid axle suspension with watt’s link assembly is mounted on the chassis-frame which is rigidly fixed to ground, and loads are achieved through hydraulic actuators at Wheels.

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.

Ethanol-gasoline blended fuels have been widely implemented in Indian markets followed by the Govt of India’s road map as ethanol reduces life-cycle greenhouse gas emissions and improves anti-knock performance. However, effects of Ethanol Blending on engine out emissions characteristics including particulates from gasoline direct injection (GDI) engine remains under development and investigation. In this study the effect of ethanol blended gasoline fuels with two blending rates 10% and 20% (v/v %) on catalyst conversion efficiencies and emissions on a 1.2 litre 3-cylinder turbo GDI engine is investigated. The addition of ethanol to gasoline fuel enhances the Octane rating (RON) of the blended fuels, oxygen content and changes Reid vapor pressure (RVP). The influence of lambda biasing, and lambda trim controller has been tested. The approach for calibration was adopted based on achieving the target pollutant conversion efficiencies.

In the current era, vehicle manufacturers focus has increased towards passenger comfort and one of the key areas is NVH. Vehicle level NVH targets are cascaded to component level for obtaining better refinement in cabin. One such performance attribute is sloshing noise of urea in diesel vehicles. Migration from BS4 to BS6.2 norms demand complex technological changes to automobile manufacturers to add extra components to the vehicles which is a big challenge in identifying the locations at critical stage of the project phase. In one of the developments of mid SUV category vehicle, sloshing noise from urea tank is perceived as objectionable during low-speed braking and while passing over speed breakers. This paper addresses the measurement conditions of sloshing noise and its evaluation procedure to quantify the sloshing noise at vehicle level. The sloshing noise is perceived in the frequency band of 50 to 1000 Hz.

Globally all OEMs are moving towards electric vehicle to reduce emission and fuel cost. Customers expect highest level of refinement and sophistication in electric vehicle. At present, the customers are sensitive to high pitched tonal noise produced by electric powertrain which gives a lot of challenges to NVH engineers to arrive at a cost-effective solution in less span of time. Higher structure borne tonal noise is perceived in electric vehicle at the vehicle speeds of ~ 28 kmph, 45 kmph and 85 kmph. The test vehicle is front wheel drive compact SUV powered by motor in the front. The electric drive unit is connected to cradle and subframe with help of three mounts. Transfer path analysis (TPA) using blocked forces method is carried out to identify the exact forces of the electric drive unit entering the mounts. Powertrain mount is characterized by applying the predicted forces and dynamic stiffness at problematic frequency is measured.

BS6.1 emission standards were implemented in India in 2020 followed by BS6.2 which added more controls on emission limits. For BS6.2 OBD (On Board Diagnostics) and RDE (Real Driving Emission) were added on to the existing BS6.1 emissions. Emission control changes usually need addition of new parts, calibration changes and durability requirements. For the current 1.5L, 3-cylinder diesel engine an pSCR (Passive Selective Catalytic Reduction) brick was added for control of NOx for meeting RDE. For meeting OBD requirements PM (Particulate Matter) and NOx sensors were added in the cold end pipe along with calibration changes to meet the BS6.2 norms. In this paper we will discuss on the design aspects of sensors and pSCR only. The sensor and pSCR positioning plays vital role in meeting the legislative requirements and to ensure the ease of assembly and durability of the parts.

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.

The test vehicle is All Wheel Drive (AWD) vehicle which is powered by four-cylinder engine. The power is transferred from the powertrain to the wheel through power transfer unit (PTU), propeller shaft, flexible rubber coupling and Integrated Rear Differential Assembly (IRDA) . Higher boom noise and vibration levels are observed when driving the vehicle in 4th gear WOT conditions. NVH levels are dominant between 1150 rpm to 2100 rpm and at 2200 rpm in 2nd order and 4th order respectively. Operational deflection shape (ODS) analysis is carried out on entire vehicle to identify the location where maximum deflection is observed at the problematic frequency. It is identified that higher torsional excitation from the powertrain is exciting the IRDA pitching mode and the propeller shaft bending mode which is the reason for higher 2nd order and 4th order NVH levels. The driveline forces are entering the body through the IRDA and rear cradle bushes.

The implementation of TREM/CEV 5 emission norms on farm equipment will bring in cost pressure due to the need for exhaust after treatment systems. This cost increase needs to be reduced by bringing in more efficient and effective processes to shorten the development phase and to provide better fuel efficiencies. In this work ETAS ASCMO Online DoE with Constraint Modelling (ODCM) was applied to execute smart online DoE on a new common rail diesel engine with EGR, whose exact bounds of operation was not available. A Global test plan with ASCMO Static was created without much focus on detailed constraints of engine operation, other than the full load curve. The parameters which were selected were Speed, Torque, Rail Pressure, Main Timing, EGR Valve Position, Pilot Separation and Quantity and Post Quantity and Separation. For these parameters, the safe operating bounds were not available. This ASCMO Static test plan is automated and executed on engine test cell with ETAS INCAFlow.

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.

Commercial transportation is the key pillar of any growing economy. Light and Small commercial vehicles are increasing every day to cater the logistics demand, but there is always a gap between customer’s actual and desired operational efficiency. This is because of lack of organized fleet and efficient fleet operation. The major requirement of fleet owners is timely delivery, high productivity, downtime reduction, real time tracking, etc., Automakers are now providing fleet management application in modern LCV & SCV to satisfy the fleet operator requirement. However, any feature malfunction, consignment mismatch, wrong notification, missed alerts, etc., can incur huge loss to fleet operator and disrupt the entire supply chain. Hence it is very critical to extensively validate the telematics features in fleet management application. This paper explains the approach for exhaustive validation strategy of fleet management applications (B2B) from end user perspective.

Electric vehicles (EV) are much quieter than IC engine powered vehicles due to less mechanical components and absence of combustion. The lower cabin noise in electric vehicles make customers sensitive to even small noise disturbances in vehicle. Road boom noise is one of such major concerns to which the customers are sensitive in electric vehicles. The test vehicle is a front wheel driven compact SUV powered by electric motor. On normal plain road, noise levels are acceptable but when the vehicle has been driven on coarse road, the boom noise is perceived, and the levels are objectionable. Multi reference Transfer Path Analysis (MTPA) is conducted to identify the path through which maximum forces are entering the body. Based on MTPA, modifications are proposed on the suspension bushes and the noise levels were assessed.

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.

As the world rapidly moves from IC engine powered vehicles to the ‘more sustainable’ electrified vehicles, the Powertrain Mounting System needs to be re-engineered to meet refinement requirements of customer. Electric vehicles are quieter but due to lack of the “masking effect”, are sensitive to minor disturbances that are perceived to be objectionable by passengers. Also, E-powertrains are lighter, produce higher torque at low rpms & operate at higher rpms which calls for different countermeasures for mounting systems compared to conventional single isolation 3-point mounting system as used in IC engines. Double isolation mounting system, where powertrain is connected to an auxiliary mass (sub frame/cradle) via mounts, which is suspended to the vehicle body via subframe bushes results in 12 rigid body modes, 6 for each mass, is highly effective in lowering the transmission of vibration at high frequencies.