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This paper discusses the development of an all speed governed diesel-natural gas dual fuel engine for agricultural farm tractor. A 45 hp, 2.9 liters diesel-natural gas dual fuel engine with a novel closed loop secondary fuel injection system was developed. A frugal approach without any modification of the base mechanical diesel fuel injection system was followed. This approach helped to minimize the cost impact, while meeting performance and emissions at par with neat diesel operation. Additional cost on gas injection system is redeemed by cost savings on diesel fuel. The dual fuel technology developed by Mahindra & Mahindra Ltd., substitutes on an average approximately 40% of diesel with compressed natural gas, meeting the TREM III A emission norms for dual fuel while meeting all application requirements. The governing performance of the tractor was found to be superior than base diesel tractor.

Rotavator is an active tillage implement for breaking the Soil and for the preparation of seed bed for cultivation. The Farmers are currently facing problem due to usage of sub optimal speed of Rotavator which results in more fuel consumption, takes more time for completion of operation. Also, the Current Rental models work on Tractor + Implement as rental combination and customer not able to rent Rotavator as a standalone implement due to non-availability of Tracking information such as hours of utilization on Rotavator. Farmers not able to maintain the service periodicity, if oil change not done in prescribed duration then it may result in improper maintenance and breakdown of the Rotavator. To overcome these problems a smart Rotavator developed consists of an electronic unit fitted on the Rotavator shaft to measure the speed of the shaft rotation and in turn convert to Rotavator speed and also able to convert into Hours of usage based on the starting and stopping of the rotavator.

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.

The braking systems for modern day commercial vehicles with GVWs ranging above 7.5 metric tons use the typical s-cam drum brake system, where pressurized air is the actuating medium. The s-cam drum brake systems are popular today even after the advent and penetration of air disc brake systems, the main reasons being, cost-effectiveness, robustness, satisfactory performance and good component life. However, the brake systems of commercial vehicles (both M and N category) are frequently grappled with NVH issues particularly in the form of brake squeal noise (low frequency and high frequency). The noise with frequency more than 500 Hz can be generally defined as brake squeal. There has been a lot of work done and is being continued, at theoretical level, analytical level and experimental level to tackle with this issue.

One of the major discomforts while driving any medium to heavy commercial vehicle is brake judder. Brake judder can be defined as vibrations felt on steering wheel or brake pedal or cabin floor, when brakes are applied at certain speeds and pressures. The frequencies of this judder lie as high as 100 Hz to as low as 20 Hz. The brake judder is caused by a number of factors, which makes providing a universal solution difficult. Some of the causes are related to part fitment, part quality, material selection, manufacturing process, Design consideration, environmental factors, etc. This paper gives us a brief idea about resolution of judder problem in intermediate commercial vehicle by series of trials and this methodology can be applied in heavy commercial vehicles also. This paper gives reader an insight about step by step root cause analysis of brake judder on actual vehicle and an approach in resolving the judder problem.

S-cam air brake system is provided in almost all commercial vehicles having tonnage above 7.5-ton. In S-Cam brake system, drum to brake lining gap (henceforth referred to as ‘brake lining gap’ or simply ‘gap’ for convenience) range is an important factor which can impact braking behavior during brake application. Different OEMs (Original Equipment Manufacturers) define different brake lining gap ranges between S-cam brake lining and drum. This range depends majorly on the internal mechanism deployed in ASA (Auto Slack Adjuster). When these brake lining gaps start lowering i.e. when they fall in the range of 0 to 0.4 mm, or they become unstable (checked by feeler gauge at inspection window provided on dust cover of S-cam) then it starts impacting brake behavior in the subject vehicles.

This paper deals with setting of Inspection parameters for selected automotive transmission parts in various bench tests. This paper we are discuss about critical dimension's measured for particular type of test. It is not possible to measure all the dimensions of a component for doing a particular test. This is due to time constraints set by program delivery deadlines. From above statement it can be deduced that it is almost impossible to measure all dimensions of a component. A bench level test may consist of two major tests. They are maximum load test and gear shift durability test. The maximum load test deals with gear box durability test and torque carrying capacity of gearbox. Parameters to be measured for some of above parts will be identified. More importantly it will also identify see reasons for that parameter to be measured.

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.

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.

Model based calibration is extensively used by the automotive OEMs (Original Equipment manufacturers) because of its correlation accuracy with test data and freezing the operating parameters such as injection timings, EGR rates, fuel quantity etc. The prediction of Brake specific Fuel consumption (BSFC), Exhaust and intake temperatures are very close to test data. The prediction of Brake specific NOx is directionally reliable with acceptable tolerance.

This paper reviews application of D-Cycle technology to compact tractor diesel engine for improving efficiency & power. The study considers design challenges that are presented for accommodating D-Cycle technology in engine. The paper also covers resolving those challenges with established technical solutions. The study focuses on modifying conventional compact 4-stroke diesel engine with the intention of keeping design changes to a minimum level for incorporating differential stroke technology. Designing of vertically splitting lightweight piston crown which can be smoothly engaged and separated from main piston body without any impact, stem rod which connects piston crown with rocker arm, split connecting rod and rocker arm which is actuated by extra actuating camshaft in addition of present valvetrain camshaft, are covered. Lubrication of additional actuating camshaft is done by extending existing oil galleries.

PVC (polyvinylchloride) synthetic leather or called leatherette is being widely used for automotive interior applications for seat cover, gear boot, gap hider, steering wheel and roof liner due to their leather like feel and texture, flexibility, sewability, affordability, and wide design freedom. However, the leatherette construction such as top coating, backing fabric and fabric weaving pattern plays a critical role in the finished leatherette performance for the specific application. This study provides the influence of different coating material and different backing fabric in squeak behavior of gear boot PVC leatherette. The squeak behavior was studied by stick slip test as per automotive engineering requirements, and the response of these coating and fabric surface was measured in the form of Risk Priority Number (RPN).

The tractor usage is growing in the world due to derivative of rural economy and farming process. It needed wide range of implements based on the applications of the customer. The tractor plays a major role in Agricultural and Construction applications. In a tractor, hydraulic system is act as a heart of the vehicle which controls the draft and position of the implement. Hydraulic system consists of Powertrain assembly, 3-point linkage and DC sensing assembly. The design of hydraulic powertrain assembly is challenging because the loads acting on the system varies based on the type of implement, type of crop, stage of farming and soil conditions etc., Hydraulic powertrain assembly is designed based on standards like IS 12207-2019 which regulates the test methods for the system based on the lift capacity of the tractor. In this paper, virtual simulation has been established to optimize the design and perform the test correlation.

Agriculture tractor industry is highly competitive in the current market scenario with global majors competing in various markets. A tractor having an optimum design is of prime importance to keep the cost low while providing higher value to the customers. Technology advances in instrumentation methodology and data acquisition helps not only in providing the right inputs for the design of a component/system but also very much useful for design/system optimization. Front Axle Support of an agricultural tractor is one of the structural member which is connected to the Chassis which is called skid of the tractor to which the Front Axle is mounted through Pillow block (Plummer block) arrangement to facilitate axle oscillation about the tractor longitudinal center line. Front ballast weights are mounted on a bracket which is intern mounted to the front axle support to maintain the required front reaction in various agricultural operations.

During design and development of a cabin for any commercial vehicle, meeting the strength requirements of front impact as per Indian regulation (AIS-029) is a very critical milestone. AIS-029 regulation consists of three destructive tests, i.e. Front Impact Test (Test A), Roof Strength (Test B) and Rear Wall Strength (Test C). Study of energy absorbing front cabin mount, its stiffness balance with chassis and CAE correlation with physical test is demonstrated in this study. [1]

In any engine cooling system, de-aeration capability of the system plays a very critical role to avoid over heating of an engine. In general, with recovery bottle engine cooling system there is one vent hose from radiator pressure cap to the recovery bottle and coolant in the bottle is exposed to atmospheric pressure. From this vent hose air bubbles will move to recovery bottle from the engine and radiator when pressure in the system exceeds pressure cap setting. With this arrangement, de-aeration from the engine will happen when thermostat opens only and till that time air bubbles will be in the engine only and in this time there will be chance of overheating at some critical conditions because of air pockets in to the engine water jacket and the entrained air in the cooling circuit. Also, secondly 100 % initial filling cannot be achieved.

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.

Hydraulic power train assembly of an agricultural tractor is meant to controls the position and draft of the implement depending upon the type of crop, farming stage, implement type and soil conditions. These variations induce extreme range of loads on the hydraulic system, thus making it challenging to design these components. Hydraulic connecting rod is critical component of hydraulic power train assembly. Standards like IS12224, IS4468 governs the design of hydraulic power train components which regulates the test method for hydraulic power and lift capacity of the tractor. In this paper, a virtual simulation process has been established to design a hydraulic connecting rod to meet the requirements. The hydraulic connecting rod basically functions as a short load transferring link, which is subjected to the operating hydraulic pressure of the hydraulic lifting mechanism. The current circular connecting rod is higher in weight and cost.

The Tractors are inevitable in the world due to its remarkable contribution majorly in farming process and other applications. the farming equipment needs to perform multiple applications to enhance the productivity and increased horsepower demands all-wheel drive (Refer fig. 1) or four-wheel drive option in the tractor. So, it is becoming a mandatory feature. The main objective of this study is, improving the torsional fatigue life in front axle spindle shaft by modifying the spline design and optimizing induction hardening heat treatment process in such a way that the other part of the system will have a minor or no design change. It helps us to reduce the part count variability, lower manufacturing cost and development time.

Synchronizer design optimization is being prime need for smooth gear shifting and shifting noise. Especially in tractors, synchronizers are subjected to different kinds of loads under various field applications such as Puddling, Cultivation, Haulage, Construction equipment, etc. Also, transmission housings act as a part of chassis of the tractor and hence subjected to sever bending loads. Thus, design & evaluation of tractor transmission, meeting the customer requirement is quite complex. Current trends in product development are driven by shortening development time, reduced cost and first-time-right principle. These above requirements drive tractor manufacturers to put more efforts on delivering quality, robust and reliable transmission assembly in time. Generally the synchronizer packs were validated at sub system level in test rig and further assembled on to the tractor to validate the same in tractor level it requires more time & high cost.