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Compared to the vehicles with conventional steering, the articulated frame steer vehicles (ASV) are known to exhibit lower directional and roll stability limits. Furthermore, the tire interactions with relatively rough terrains could adversely affect the directional and roll stability limits of an ASV due to terrain-induced variations in the vertical and lateral tire forces. It may thus be desirable to assess the dynamic safety of ASVs in terms of their directional control and stability limits while operating on different terrains. The effects of terrain roughness on the directional stability limits of an ASV are investigated through simulations of a comprehensive three-dimensional model of the vehicle with and without a rear axle suspension. The model incorporates a torsio-elastic rear axle suspension, a kineto-dynamic model of the frame steering struts and equivalent random profiles of different undeformable terrains together with coherence between the two tracks profiles.

Agriculture Tractors are widely used as prime mover either to pull or drive the “Implements” in the farms, apart from custom made equipments like Transplanter, Manure Spreader, Combine Harvester, Cotton Picker, mobile irrigation etc. which are used for particular operations in large production capacities. For larger landholdings, timely completion of the operation within the window period is the major decisive factor that drives agriculture tractor design. For small farms like in India, the productivity requirement was offset by the versatility of the equipment. Also, the farming practice varies in India due to geographical conditions such as soil types and demographic conditions such as crops types. Hence, the mechanisation level of matured market was not yet achieved in India, though the technologies are available for implementation.

To improve overall customer experience, it is imperative to minimize the noise levels inside agricultural equipment cab. Up-front prediction of acoustic performance in product development is critical to implement the noise control strategies optimally. This paper discusses the methodology used for virtual modeling of a cab on agricultural equipment for prediction of interior noise. The Statistical Energy Analysis (SEA) approach is suitable to predict high frequency interior noise and sound quality parameters such as articulation index and loudness. The cab SEA model is developed using a commercial software. The structural and acoustic excitations are measured through physical testing in various operating conditions. The interior noise levels predicted by the virtual model are compared with the operator ear noise levels measured in the test unit. The resultant SPL spectrum from SEA correlates well with the test.

The evolution of engine technology has so far seen the most beneficial side of progress in the fields of transportation, agriculture, and mobility. With the advent of innovation, there is also an impact on our environment that needs to be balanced. This is where fuels like CNG, LPG, LNG, etc. outperform conventional fossil fuels in terms of pollution & operational cost. This paper enlightens on the use of innovative dual-fuel technology where diesel & CNG fuels are used for combustion simultaneously inside the combustion chamber. Dual fuel system adaptation for farm application ensures self-reliance of the farmer where he can generate Bio-CNG to use the renewable fuel for farming making him less dependent on conventional fossil fuel thus promoting a green economy. The dual-fuel system is adapted to the existing in-use diesel engine with minimum modifications. This makes it feasible to retrofit a CNG fuel system on an existing diesel engine to operate it on dual fuel mode.

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.

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.

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.

Reliability and cost effectiveness of electronics demands its usage in all the wings of science and technology. Thus an attempt was made in this work to investigate the potential of using electronics for injecting primary fuel for the compression ignition engine used by farmers for agricultural purpose. In the first phase of the work, a new Electronic Control Unit (ECU) for primary fuel injection was developed and tested for its repeatability on fuel injection quantity for the different input voltages. Test engine was developed and tested under various load condition for its performance, emission, and combustion characteristics with neat diesel and Waste Cooking Oil Methyl Esters (WCOME) as baseline readings in the second phase of the work. In the third phase of work, the developed engine was modified to operate in duel fuel mode with developed ECU. In this work, ethanol was chosen as primary fuel due to its availability and less toxic nature as compared to other green fuels.

In a modern world, the tractor customer demands are increasing for more comfortable, new technology, fuel efficient and quieter vehicle. The customer’s expectation for NVH refinement often challenges the limitations for tractor designs. For smaller tractors Hydrostatic Transmission (HST) is need due to higher demand for fuel efficiency, lightweight powertrain, and the operation will become easy in the farm field. With the Hydrostatic Transmission (HST) tractor without damper, there is a technical challenge like withstanding of the sudden impacts from the implements which are connected to PTO during field operations. The NVH behavior in driveline is critical phenomena which can cause the discomfort to end users and structural failure of driveline parts. During gear engagement due to sudden variation in torque the driveline parts are tends to clash each other because of lashes which will create high level of angular acceleration and noise.

This paper presents a study related to an Articulated Amphibious All-Terrain Tracked Vehicle (ATV) characterized by a modular architecture. The ATV is composed by two modules: the first one hosts mainly the vehicle engine and powertrain components, meanwhile the second one can be used for goods transportation, personnel carrier, crane and so on. The engine torque is transmitted to the front axle sprocket wheel of each module and finally distributed on the ground through a track mechanism. The two modules are connected through a multiaxial joint designed to guarantee four relative degrees of freedom. To steer the ATV, an Electro Hydraulic Power System (EHPS) is adopted, thus letting the vehicle steerable on any kind of terrain without a differential tracks speed. The paper aims to analyze the steady-state lateral behavior of the ATV on a flat road, through a non-linear mathematical vehicle model built in Matlab/Simulink environment.

This SAE J2971 Recommended Practice describes a standard naming convention of aerodynamic devices and technologies used to control aerodynamic forces on truck and buses weighing more than 10000 pounds (including trailers).

This SAE J2971 Recommended Practice Truck and Bus Aerodynamic Device Terminology document describes a standard naming convention of aerodynamic devices and technologies used to control aerodynamic forces on truck and buses weighing more than 10,000 pounds (including trailers).

The work presents the design of a traction electric equipment set of an electromechanical drivetrain (EMD) to be used with 300-hp-class agricultural wheeled tractors. Comparative characteristics of various drivetrain types used in agricultural tractors are presented; and the advantages of using EMDs in tractors are discussed. The EDM advantages are as follows: improved technical and economic parameters of the tractor; reduced dynamic loads on the tractor and diesel units; reduces wheel slippage; reduced fuel consumption (by up to 30%); continuous variation of speed of the tractor and aggregated implements; reduced expenses on maintenance, repair and spare parts; increased total reliability, controllability and comfort; possibility to use the tractor as a power source (optionally). Considered in combination, all these advantages clearly speak in favor of using electromechanical drivetrains.

Steering wheel vibration is one of the major factors in determining the operator comfort in agricultural tractors. Main sources of steering wheel vibration are engine imbalance, resonance of steering system, lesser damping, road / field induced vibration, etc. The European Council directive 2002/44/EC recommendations are taken as guidelines in this work. Steering vibration study was conducted on various tractor models (40 - 50 kW range) and one tractor was identified for improvement. Upon detailed analysis on that particular tractor, it was found that the resonance of steering system with engine excitation is the root cause for excessive vibration. Various methods to reduce vibration due to resonance were considered, such as shifting the natural frequency away from the second order engine frequency and increasing damping coefficient to reduce the vibration amplitude at resonance. Six different concepts were generated and analyzed using the design assessment matrix.

Agricultural tractors have traditionally used hydro-mechanical draft control systems, wherein implement draft is sensed mechanically, and through appropriate linkage, a hydraulic valve is actuated to raise and lower the implement. Mechanical linkages have inherent limited flexibility, which has been further reduced by the implementation of environmentally isolated cabs. The development of low cost, reliable microprocessors has allowed greater flexibility in the design of agricultural tractor control systems. For example, implement draft sensing need no longer be limited to top-link, lower-link or output torque monitor, but can be wheel slip, engine speed, engine load, etc. The development reported herein involves a new concept of completely eliminating the mechanical draft sensors and instead using the engine speed to determine the draft load. The engine RPM is compared with the no load RPM expected at a given throttle setting.

The Equipment Manufacturers Institute (EMI) sponsored a literature search conducted by Triodyne, Inc. which attempted to identify all “Operator Protective Zones” ever utilized in the world. This effort was intended to determine whether published information existed to define a more compact Operator Protective Zone than those of current SAE (ASAE) standards for possible utilization in developing a new standard for a more compact design of Rollover Protective Structures (ROPS) for small agricultural tractors. The research has led Triodyne to conclude that the Operator Protective Zones upon which the current SAE (ASAE) ROPS standards are based are the only substantiated zones available for possible application to small agricultural tractors.

Automatic guidance of farm tractors would improve productivity of many field operations by reducing operator fatigue and by improving machine performance. A self-tuning steering controller, which can be used for noncontact positioning systems, was designed for tractor guidance. A simple two degrees-of-freedom model was chosen with which to develop a prediction model used in recursive least-squares parameter estimation. A variable forgetting factor was implemented and its algorithm modified to cope with time-varying nonlinear systems. The self-tuning steering controller based upon minimum variance control was tested and verified with a tractor dynamic simulator. Circular, lane change, and sinusoidal paths were used. A model tractor was also used to verify controller performance for staight-line and sinusoidal paths.