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Agriculture machinery industries have always relied on conventional product development process such as laboratory tests, accelerated durability track tests and field tests. Now a days the competitive nature seen in industry concerns need to enhance product quality, time to market and development cost. Utilization of Computer Aided Engineering (CAE) methods not only provide solution but also could play key role in tractor development process. The objective is to assess the performance of virtual simulation model of mid segment farm tractor using Multibody System Model (MBS) for predicting the durability loads on virtual proving ground test tracks. Multibody simulation software MSC ADAMS is used to develop a virtual tractor model. Durability test tracks and simulation is carried out as per company testing standards. Data measurement is done using Wheel Force Transducer (WFT) to study front and rear spindle forces and moments to evaluate the virtual model performance.

Technology is one of the key determinants of the outcome in today's wars. Many targeting systems today use infra-red imaging as a means of acquiring targets when ambient light is insufficient for optical systems. Reducing thermal signatures offers an obvious tactical advantage in such a scenario. One way to reduce thermal emission of combat vehicles is to adopt highly efficient electrical power trains instead of internal combustion engines that tend to reject a sizeable amount of the input energy as heat. The tractor is one of the most versatile vehicles that are used in the theatre of combat for various operations such as haulage, clearing terrain, deploying bridges, digging trenches etc due to its excellent abilities in handling difficult terrain. A tractor powered by an all-electric power train was developed for civilian applications. The traction characteristics are identical to that of a conventional diesel powered tractor of comparable size.

Automotive clutches are rotary components which transmits the torque from the engine to the transmission. During the engagement, due to the difference in speed of the shafts the friction lining initially slips until it makes a complete engagement. Enormous amount of heat is generated due to the slippage of the friction lining, leading to poor shift quality and clutch failure. Depending on the road & traffic conditions, and frequency of engagement and disengagement of the clutch, it generates transient heating and cooling cycles. Hill fade test with maximum GVW conditions being the worst case scenario for the clutch. A test was conducted to understand the performance of the clutch, in which clutch burning was observed. The clutch lining got blackened and burning smell was perceived. The friction coefficient drops sharply to a point until it cannot transmit the torque required to encounter the slope. This further worsen clutch slippage and lead to more severe temperature rise.

This paper is an attempt to compile a systematic approach which can be easily incorporated in the product development system used in the design and development of parking brake systems for passenger cars having rear drum brakes, which in turn can effectively reduce the lead time and give improved performance. The vehicle GVW, percentage gradient and maximum effort limits (as per IS 11852 - Part 3), tire and drum brake specifications were taken as front loading. This data is used for target setting of functional and engineering parameters, such as lever pull effort, lever ratio and angular travel of lever. Design calculations were performed to obtain theoretical values of critical parameters like lever effort and travel. The comparison between target and theoretical values give the initial confidence to the system engineer. Further, the outcome was taken to conceptualize the hard points of lever on vehicle for ergonomics.

Vehicle handing and ride are the critical attributes for customers while buying new passenger vehicle. Hence it is very important to design suspension which meets customer expectations. Often tuning of suspension parameters is very difficult at later stage like wheelbase, vehicle center of Gravity and other suspension parameters like roll center heights etc. A parametric mathematical model is built to study the effect of these parameters of vehicle handling and ride attributes at concept stage. These models are used to calculate the suspension ride rates, spring rates and Anti roll bar diameters for meeting target vehicle ride and handling performance. The model also calculates natural frequency of suspension and vehicle for understanding pitch and roll behaviours.

In the conceptualization phase of vehicle development, for achieving reasonable dynamics performance, proper selection of steering system meeting all the requirements is necessary. This requires accurate prediction of major steering performance attributes like steering effort, steering torque, Turning Circle Diameter (TCD), %Ackerman and steering returnability. However, currently available models majorly depend on Computer Aided Engineering (CAE)-analysis or physical trials which requires system detailing and the same cannot be used for early prediction of the steering performances in the concept phase. This paper aims to address this deficiency with the help of a new steering performance calculator. In the calculator, performance attributes namely steering effort, steering torque, TCD and %-Ackerman has been modelled with engineering calculations and other attributes namely steering returnability&precision has been modelled through machine learning techniques.

In automotive product development, design and development of the chassis plays an important role since all the internal and external loads pass through the vehicle chassis. Durability, NVH, Dynamics as well as overall vehicle performance is dependent on the chassis structure. Even though passenger vehicle chassis has a ladder frame or a monocoque construction, small commercial vehicle chassis is a hybrid chassis with the cabin welded to the ladder frame. As mileage is critical for sale of SCVs, making a light-weight chassis is also important. This creates a trade-off between the performance and weight which needs to be optimized. In this study, a parametric beam model of the ladder frame & the cabin of the vehicle is created in COMSOL Multiphysics. The structure has been parameterized into the long member & crossmember geometry & sections. The model calculates the first 12 natural frequencies, global stiffness, and weight.

Tractor weight transfer is the most common farm-related cause of fatalities nowadays. As in India it is getting mandatory for all safety devices across all HP ranges. Considering any changes in the weight from an attachment such as Rops, PTO device, tow hook and draw bar etc. can shift the center of gravity towards the weight. center of gravity is higher on a tractor because the tractor needs to be higher in order to complete operations over crops and rough terrain. Terrains, attachments, weights, and speeds can change the tractor’s resistance to turning over. This center of gravity placement disperses the weight so that 30 percent of the tractor’s weight is on the front axle and 70 percent is on the rear axle for two-wheel drive propelled tractors and it must remain within the tractor’s stability baseline for the tractor to remain in an upright position.

The purpose of a differential is to allow the wheels of an automobile to turn at different speeds so that it does not skid during turning. However when a vehicle runs on a slick or muddy surface (especially in Agricultural and constructional Field applications) that same feature causes the wheel with less traction to spin freely as this unit transmits power to the tire with least amount of traction. The function of a difflock is to lock the differential gears, by locking the differential, both the axles receive equal power and hence equal traction is available at both the tires. This Paper describes the positive locking of a differential by stopper, and also in detail the problems associated with its engagement and disengagement in tractors and construction equipment's. Additionally a concept for a difflock stopper which has been experimentally proven for tractors and construction equipment's is also discussed.

Battery Electric Vehicles (BEVs) are gaining momentum all around the world and India is not far behind in terms of EV sales. The principle difference between BEVs and Internal Combustion Engine based Vehicles (hereafter known as ICEs) is that BEVs run on electric motors and don’t have Internal Combustion based engines that generate significant noise while running. The engine noise contributes to noise pollution, but it is useful in alerting the pedestrians about the incoming vehicle and can function as a passive safety system. The lack of such noise can be a safety threat to pedestrians, cyclists, wildlife etc. Many countries around the world have mandated, or are in the process of mandating, a pass-by noise generating system to alert pedestrians about the incoming vehicle. This paper is an attempt to study various pass-by noise generating systems used worldwide in electric four-wheelers.

In recent times, Battery electric vehicles (BEV) have gained a lot of popularity since they can contribute immensely to control the urban air pollution. However, to consider the BEVs as a sustainable mobility solution, a significant improvement is needed in several aspects including performance, range, cost, weight and recharging time. In the present work, the acceleration performance of an electric vehicle is improved to match with its diesel variant by optimizing the accelerator pedal map strategy. Due to weight and cost constraints, the battery and electric machine capacity of the electric variant of the vehicle was considerably lower (41 % lesser power and 44% lesser torque). However, the expectation from the customers is to have no noticeable difference in the low-end performance feel between the variants.

Vehicle frame evaluation at early stages of product development cycle is essential to reduce product turnaround time to market. In conventional approach of virtual validation it is required to evaluate the strength of the vehicle structure to account for the standard Service Load Analysis (SLA) loading conditions. But this paper describes on the strength analysis of scooter frame with derivation of critical static load cases. The critical load cases are extracted from the load-time history while the vehicle was simulated on durability virtual test rigs which is equivalent to proving ground tests. This methodology gives the better accuracy in prediction of stress levels and avoids the overdesign of components based on traditional validation technique. There is significant drop in stress levels using the critical load case approach as compared to conventional load case method.

Tractors with 4WD drive perform better in slick, off road or muddy conditions (especially in Agricultural and constructional Field applications) where torque is required at all the wheels. The purpose of four wheel drive or all-wheel drive is to transmit power to all the wheels. In case of 2WD the power from engine is transferred to the rear wheels of a tractor through transmission. But in case of 4 WD tractors and construction equipment, power from engine is transferred to the front wheels through drop box and the driveline (propeller shaft). This Paper describes the need of an offset driveline where there is an offset between the Drop box output shaft center and the front axle input shaft center. This offset is the result of zero keel angle of the tractor. In order to maintain zero keel angle and transfer power to front wheels, an offset driveline with three shafts has been design &developed.

Nowadays, tractors are frequently used with front-end loaders, dozers and backhoes to cater to various non-agricultural and construction application needs. These applications require frequent shifting of gears due to the constant need for a tractor's forward/reverse direction of motion. Hence, the tractors are fitted with a power shuttle transmission (PST) to cater this need. Power-shuttle transmission (PST) development is a design process that incorporates multiple disciplines such as mechanical, hydraulics, controls and electronics. This paper presents a simulation-based approach to model the power shuttle transmission of the tractor. Firstly, individual components of PST are modelled in detail and then integrated with the complete tractor model. For this, GT-Suite has been used as a simulation platform.

The Ride Comfort has always been an important attribute of a vehicle that gets trade-off with handling characteristics of a vehicle. However, to cater the growing customer requirements for better ride comfort in a vehicle without compromising on other attributes, evaluating and achieving optimal ride comfort has become a significant process in the vehicle development. In the current engineering capability and virtual engineering simulations, creating an accurate and real time model to predict ride comfort of a vehicle is a challenging task. The qualitative evaluation of ride attributes has always been the proven conventional method to finalize the requirements of a vehicle. However, quantitative evaluation of vehicle ride characteristics benefits in terms of target setting during vehicle development process and in robust validation of the final intended product against its specifications.

This paper details the methodology used to show the importance of Low rolling resistance tires in Electric Vehicles. Fuel efficiency and range is paramount with most of the electric vehicle buyers. Although many people are now becoming aware of low rolling resistance tires but its development started way back in 1990’s. It is always challenging to achieve low rolling resistance in smaller tires of size 12 inch or 13 inch along meeting the other critical vehicle parameters such as ride and handling, NVH, durability and many more. The reduction in rolling resistance can also affect the traction properties of tires. In case of very low rolling resistance tires the traction will be very less but it can badly affect the other vehicle parameters. Selection of tires further depend upon the RWUP (Real World Usage Profile). It means the vehicle is targeted for which region and what is the condition of roads there.

Body-over-Frame is the primary type of construction used in SUVs, pick-ups, and other commercial vehicles in India. In this type of construction, the body, engine, suspensions etc. are mounted on the ladder frame. Since the frame acts as the skeleton of the vehicle, optimal design of frame at the concept stage of the vehicle program is critical for meeting all structural performance targets. Frontloading of these targets aids in architecture development and reduces future design modifications. The natural frequency response from the frame directly affects the NVH performance of the vehicle. This paper focuses on frontloading the natural frequency targets by performing concept-level simulations on the ladder frame even before creation of 3D concept data. A parametric beam model is created based on the reference vehicles. The beam model has been validated with correlation of more than 85% compared with CAE and physical testing outputs of existing vehicles.

Being a safety critical aggregate, every aspect of brake system is considered significant in vehicles operations. Along with optimum performance of brake system in terms of deceleration generation, brake pedal feel or brake feel is considered as one of the key elements while evaluating brake system of vehicles. There are many factors such as liner and drum condition, road surface, friction between linkages which impress the pedal feel. Out of these, in this paper we will be discussing the factors which influence the brake pedal feel in relation to the driver comfort and confidence building. Under optimum braking condition, brake operation must be completed with pedal effort not very less or not very high, brake pedal feel must be firm throughout the operation, in such a way that it will not create fatigue and at the same time it will give enough confidence to the driver while operating with acceptable travel.

Globally, automotive sector is moving towards improving off-road performance, durability and safety. Need of off-road performance leads to unpredictable overload to powertrain system due to unpaved roads and abuse driving conditions. Generally, shafts and gears in the transmission system are designed to meet infinite life. But, under abuse condition, it undergo overloads in both torsional and bending modes and finally, weak part in the entire system tend to fail first. This paper represents the failure analysis of one such an incident happened in output shaft under abuse test condition. Failure mode was confirmed as torsional overload using Stereo microscope and SEM. Application stress and shear strength of the shaft was calculated and found overstressing was the cause of failure. To avoid recurrence of breakage, improvement options were identified and subjected to static torsional test to quantify the improvement level.

Selection of EGR system is very complex for a particular engine application. The performance of the EGR system depends highly on the Cooler Heat Transfer Efficiency. Cooler effectiveness drops over a period of operation due to soot deposition, HC condensation, and fuel quality. This phenomenon is called as Cooler Fouling. Fouling cannot be avoided completely but the level of performance drop over time has to be studied and minimized. The minimum pressure drop and the highest efficiency in fouled condition is the target for selection of a cooler. In this study, various parameter combinations like tube shape and profile, tube length, number of tubes, tube diameter, and pitch of corrugations, which influence the cooler performance were tested. A better understanding of each of its effect on cooler effectiveness and fouling behavior was obtained. The tube shape was changed from rectangular to circular, also from smooth surface to corrugate.