Tractor and Farm Equipments Research Papers (original) (raw)

Automobiles running on our streets are furnished with the most essential part at the rear side called as differential. This is the part which transmits relative power to both the back wheels while turning. An ordinary differential, that is open differential dependably supplies near equivalent torque to each side. With an automotive differential if one of wheels on the axle is held stationary, the counterpart wheel turns at twice its ordinary speed. The differential gearbox is one, in the event that we lock any of the component in gearbox then entire gearbox will bolt and the back-hub shafts will fill in as a single shaft. To have easy differential locking system the distinctive parts utilized are spike, shaft, and dog ring and dog moving selector component.
These types of rear diff locks are very useful in the off-road vehicles. They are very prominent in heavy trucks and especially tractors. This locking system is run through hydraulic or electronic actuation. The front axle is different from real axle in terms of loads acting and sizes. This project aim is to design a new differential locking concept for 4-wheel drive tractors taking the space and load constrains. Locking of differential works through the hydraulic system which is primarily actuated by electronic switch.

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- Mechanical Engineering, Hydraulics, Automobile, Tractor and Farm Equipments

У статті представлено результати теоретичних досліджень кінематичної невідповідності і динамічної нерівномірності навантаження спарених коліс, їх вплив на реакції з боку ґрунту та втрати потужності трактора. У роботі наведено випадок використання здвоєних коліс з різним тиском у шинах та різним вільним радіусом. У результаті маємо систему паралельних сил, для якої можна записати тільки два рівняння рівноваги статики при чотирьох невідомих реакціях. Задача двічі статично невизначена. Для її вирішення методом сил необхідно скласти два рівняння сумісності деформацій. Деформація ґрунту під шиною може бути визначена одним з методів, які використовуються в розрахунках фундаментів. У нашому випадку при невеликому значенні власної ваги і високій пористості верхнього шару ґрунту можна використовувати наближений метод Розенфельда.

The Response Surface Methodology (RSM) is used here to analyse a large set of experimental data regarding the mechanical and environmental performances of an internal combustion engine (ICE) used to power a farm tractor. The aim is twofold: (i) to demonstrate the effectiveness of RSM in quantitatively assessing the effects of biofuels on a complex system like an ICE; (ii) to supply the users with easy-to-use models to predict the effect of biofuel blends on performance and emissions of tractor engines and find an optimal blend according to given user-defined parameters. The methodology showed good prediction abilities: the calculated average errors for the first models were lower than 0.38 and 1.40% on 6 test cases, with a higher accuracy in the assessment of the ICE mechanical performance. As a result, two effective and user-friendly models for torque and NOx emissions were developed; they were subsequently used to single out some fuel blends having interesting effects in terms of ...

- by Fabrizio Mazzetto
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- Agricultural Engineering, Environmental Science, Biodiesel, BIOETHANOL

Finding solutions to farm problems and issues is a painstaking process which requires acceptance of new body of knowledge that may disprove and invalidate some long held theories and "truth". Poor and small (landowners of 3 has. and below) veteran Filipino farmers refrained from use while newly-bred farmers are reluctant to use the farm-machine---2WT, due to high-cost of fuel and or rental fee for the tractor which usually owned by merchants engaged in usurious cash-lending and rice trading. They prefer the hard way of farming to save a little amount for the socio-economically struggling family from tractor expenses contribution. The researcher-proponents, Automotive Technology students from College of Technology, Eastern Visayas State University, coached by Rannie C. Agustin, are investigating for the feasibility of manufacturing cost-efficient solar-powered 2WT to help the poor Filipino farmers increase their farm productivity, easing the hard-way of farming with efficient and effective farm technology as tools for strategic and engineered timely land preparation and sowing, harvesting, threshing, processing and transporting. All of which, according to Biggs & Justice (2015) lead to productivity gains and increases in cropping intensification through quicker and higher turn-around or turn-overs of production cycles.

Application of rotary tillage has been increased due to less tillage passes required, reduced draft, and greater efficiency through reduction in wheel slippage. Early failure of the bearing of tractor power takeoff (PTO) shaft was observed in tractors of power range 30-35 horsepower during rotary tillage. An instrumentation setup involving an extended octagonal ring transducer (EORT) was developed and installed at the bottom of the bearing to measure the axial load and the vertical component of the radial load. The horizontal component of radial load was measured by strain gauges. Based on measured loads, the bearing life was assessed. Independent variables were: operating depth, number of blades, gear setting, engine speed, and tyre size. The average axial and radial loads varied from 786-3869 N, and 134-430 N, respectively. However, bearing experienced very high peak loads during each trial. The peak axial and radial loads was recorded between 1081-7534 N and 566-1794 N, respectively. The estimated bearing life based on peak loads was 171.98-28341.39 h. Based on the findings, it may be concluded that the average loads were not sufficient to cause quick failure of PTO bearing, rather sudden peak loads might be the root cause of early failure.

This report deals mainly with maintenance of agricultural machinery in the Ho Municipality. The report emphasizes the tractor, because it is the major tool for agricultural mechanization in the Ho Municipality.
The report aims to identify the present status of agricultural machinery maintenance within the Municipality, the problems faced by tractor owners and operators when they undertake maintenance and the new approaches to agricultural machinery maintenance in the Ho Municipality. A survey of 50 tractor owners and operators in the Ho Municipality was conducted to identify their personal profile, their perception about the causes of tractor breakdown, and the major constraints affecting tractor maintenance and repair in the Municipality. Data was collected using questionnaires and this was administered to respondents who were the tractor owners and operators in the Ho Municipality. The data collected yielded some of the following results; farming in the Ho Municipality was male dominated, the most recurring age of the respondents was 25-40 years old, educational level of the respondents was above average. Also, tractor owners and operators perceived the causes of tractor breakdown to be careless tractor operation, inadequate maintenance, aged tractors, poor roads to farms, use of fake spare parts for tractor maintenance and repair, and obstacles to tractor operation in the farms including stumps, roots, and buried stones. Checking of water level in the radiator, checking the engine oil level, tightening of bolts and nuts, checking tire pressure, changing of engine oil, changing of oil and fuel filters, changing of worn out parts of the tractor and general overhauling at the end of the year was identified to be some of the maintenance schedule followed the tractor owners and operators. The major constraints affecting tractor maintenance and repair were found to be high cost of genuine spare parts, and lack of financial credit. The study draws attention to the need for the provision of financial credit, subsidized genuine spare parts and quality after-sales-service to tractor owners and operators as a recommendation.

Identification of the usage and features of tractors by conducting a survey among tractor owners of Kerala.

La adquisición y compra de tecnología es un trabajo al que se enfrentan muchos productores agrícolas. En
este artículo se presenta un modelo multicriterio para seleccionar un tractor de un conjunto de cinco posibles alternativas,
donde se han evaluado aspectos cuantitativos y cualitativos que tenían diferentes niveles de importancia. Se usó el método
MOORA para realizar la evaluación y se determinó el tractor que debía elegirse de acuerdo a las necesidades propias de
un grupo de productores agrícolas.

The most well-known reason of global warming is equivalent carbon dioxide (CO2equ) emitted from fossil fuels combustion in on-road and off-road vehicles. An appreciable portion of off-road pollution is allocated to farm implements. All cited studies have shown that renewable based electric vehicles (EVs) decrease petroleum consumption and consequently reduce criteria emissions under nearly all circumstances. Considering this, a Solar Assist Plug-in Hybrid electric Tractor (SAPHT) was designed, constructed and evaluated. This research evaluated the life cycle analysis of SAPHT project and compared the results with that of an internal combustion engine tractor (ICET). The life cycle was analyzed based on economical cost and environmental emissions. The externality of environmental pollutions was calculated to derive the life-cycle costs (LCC). The results showed that substituting each ICET by SAPHT can prevent 14 ton CO2equ emission to atmosphere annually. Also it prevents a high volume of other emissions such as CO, NOx and PM10 entering the atmosphere. LCC assessment emphasizes on economical effectiveness of SAPHT rather than ICET at any diesel fuel price, therefore, increasing fuel unit prices leads to more effectiveness. It is concluded that levelized cost of energy (LCE) in €/kW h for ICET is almost twice as that of SAPHT. Some of these advantages for SAPHT are offset in part by high purchase costs, heavy and massive batteries and low operating range.

The TRAKTnet.one project aims to identify and develop new solutions to remotely monitor the efficiency of farm-tractors engines included in a local voluntary network. The knowledge of tractors’ efficiency can give important information concerning machines’ consumption, emissions and need for servicing, thus contributing to a more environmentally-sustainable agriculture. Engines will be monitored by measuring rpms, exhaust gas temperature and oxygen content (through lambda sensors) and then analysing and inferring the data through procedures, which algorithms will be an integral part of the project’s results. Trials will be performed on different engines and at different speeds/loads. The choice of the thermocouple type and installation point must be done carefully for not influencing sensitivity and response time. The final outcome of the project is expected to be an automatic system, based on an inference software-engine able to correctly interpreting the sensors outputs. The advantage of this proposal is to exploit a farm monitoring network, previously designed for managing the information related to the automatic compilation of records in the country, by simply equipping data loggers with two additional sensors.

Proper matching of tractors and implements is
crucial for maintaining high operational efficiency on the farm. An object-oriented program in
Visual C++ was developed to predict the performance of tractor-implement system. The Brixius
Model and ASAE Standards D497.5 were used to predict the tractor performance and implement draft
respectively. A simulation subroutine in the program selects the optimum field speed that matches
the pull provided by a tractor with the Draft requirement of an implement and displays some
performance parameters of the tractor-implement system. Tractor and implement performance
parameters such as field speed, drawbar pull, drawbar power, total implement draft, field capacity,
and actual operating hours are predicted for the selected tractor- implement system. The program is
appropriate for farm machinery management, educational and research purposes. It is user-friendly
and could be run on Windows desktop with or without Visual C++ environment. The databases of the
tractors and implements could be edited and/or updated to suit the
required task of the user.

- by MOHAMMED SHU'AIBU ABUBAKAR
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- Tractor and Farm Equipments

Tillage is a very important practice in agriculture in many countries and accounts for more traction energy than any other field operation. Tillage operation consumes up to 59% of all diesel fuel required for the complete technology so reduced tractor fuel consumption during tillage will result in both environmental and agricultural economic benefits. Several attempts have been made to study the fuel consumption of the agricultural tractor in order to minimize it to acceptable levels during the tillage operations. Some factors like tillage speed, depth, ballast weight and tires inflation pressure of the tractor can affect the tractor fuel consumption. This article reviews these factors to give possibility for further research to focus on the potential solutions to decrease the fuel consumption of the agricultural tractors.

Forestry and agricultural tractors are required to have roll-over protective structures (ROPS) for use on European roads. To that end, the ROPS must conform to a series of strength tests in accordance with the Organisation for Economic and Co-operation Development (OECD) Standard Codes or the relevant European Community (EC) Directives. Within these Codes, ROPS force and energy absorption test requirements are typically defined in terms of a ‘reference mass’. This mass, along with mass values for ‘unladen’, ‘ballast’, and ‘maximum laden’, required for the homologation documentation, is given by the tractor manufacturer. Recent international interest in operator safety has questioned the appropriateness of the mass definitions and specifically the use of the currently defined reference mass as the basis for ROPS testing. In this work, mass information pertaining to 24 wheeled type tractors was considered: 13 were T1 (Standard) type and 11 were T2 (Narrow track) type. Although tractors may have similar reference mass values (and hence ROPS testing requirements) it was found that their ballast and maximum laden masses can differ greatly. The average ratios to reference mass values were for ballast and maximum laden values 1.13 and 1.60 for T1 tractors and 1.12 and 1.64 for T2 tractors. Both tractor categories had some ratios with values greater than 1.80. This implies safety margins determined by reference mass vary depending on the tractor under consideration. The results highlight some criticisms of ROPS testing procedures and these are discussed.

- by Nur Aini Mohamad
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- Agronomy, Agriculture, Tractor and Farm Equipments

A wireless instrumentation system was successfully developed and tested to overcome the constraints associated in collection of torque data of PTO-driven agricultural machinery with benefits such as no disturbance in telescopic action or vertical inclination of Cardan shaft. The system ensured no alterations in standard length of PTO driveline shaft. Further, telemetry system enabled remote acquisition of signals without inducing any risk of damaging the associated electronic components. It offered sensitivity of 1.6 mV/V per kN-m of applied torque with good linearity during static calibration. The performance was assessed based on accuracy, non-linearity, hysteresis, and non-repeatability and their values were 97.06%, 2.57%, 3.44%, and 0.26%, respectively. The data obtained for torque were validated with the torque computed from axial and radial load data of PTO ball bearing acquired simultaneously during rotary tillage. The low values of mean absolute percentage error (7.78% and 6.58%), maximum absolute variation (15.17% and 15.39%), and root mean square error (21.24 and 22.16 N-m), indicated good accuracy of the system. The experiments were designed with active tillage tools having two different numbers of blades, transmission gear ratios, engine speeds, tyre sizes, and four working depths as treatments. Results revealed that considered variables other than tire size, significantly affected the PTO torque and power. The decrease in PTO torque and power was found to be levelled off beyond velocity ratio 7.92. The developed instrumentation technique is simple, reliable and could be useful for database generation, implement design, and matching for effective utilization of tractor engine power.

Soil bin investigations were initiated with combined offset disc harrow (CODH) which unites the benefits of powered discs and combination tillage together through a front active-rear passive set configuration. The proposed configuration may help to achieve timeliness in sowing, better crop residue handling with reduced tillage passes and improved engine power utilization of tractor. The effects of speed ratio (u/v), front gang angle (α), operating depth and cone index (CI) on its draft, torque and power requirement were studied and compared with its traditional passively driven mode at an average soil moisture of 9–10% (db) in sandy-clay loam soil. Optimum system settings were found out before further performance evaluation in the field. The substantially reduced draft requirement with CODH might help to reduce the wheel slippage and improve field productivity while increased power requirement might prevent the under-loading of tractor engine. Tillage quality was assessed considerin...

One of the most difficult practical problems to overcome when testing agricultural machines (tractors) at the dyno is measuring the fuel consumption and assessing the engine's global efficiency. Indeed, diesel engines have two fuel-lines: a delivery line (from the tank to the cylinders), and a return line, to convey back in the tank the fuel not injected as a consequence of the accelerator position and pump settings. In principle, to measure the consumption, known the delivery flowrate (proportional to the engine speed), a single flowmeter could be used in the return line only (having a variable flow); unluckily, the real suction flowrate is generally unknown, varying with the model and vehicle age (i.e., with the pump components' wear), so two flowmeters are always needed. But there is another metrological problem to consider: a flowmeter inserted in series in a fuel-supply line could significantly alter the flowrate. Finally, another further problem can arise, when the experimenters are asked to characterize machines not owned by them: modifications to the vehicle under test should be avoided or, at least, limited, e.g., not to void the guarantee. Unfortunately, solutions like the clamp-on ultrasonic flowmeters (placed outside the pipes) are not so suitable for fluids with few particles in suspension, e.g., the fuel processed by the pump. Therefore, it was decided to act upstream of the entire supply line, providing an external tank placed on a precision scale near the tractor, to be used instead of the vehicle's tank. The only, absolutely reversible, needed operation is to connect to the fuel pump two flexible pipes drawing from the external tank. The device gives the net fuel consumption by means of a data logger that acquires the tank mass at periodic intervals. It has been successfully tested on a New Holland 4020V tractor at the dyno, allowing to calculate the instant/hourly/specific consumptions and the engine's global efficiency at six engine speeds (from 800 to 2200 rpm) and full throttle.

- by Marco Bietresato
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- Agricultural Engineering, Consumption, Energy Consumption, Alternative Fuels
- by diesel generators
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- Tractor and Farm Equipments, Generator

Soil bin investigations were initiated with combined offset disc harrow (CODH) which unites the benefits of powered discs and combination tillage together through a front active-rear passive set configuration. The proposed configuration may help to achieve timeliness in sowing, better crop residue handling with reduced tillage passes and improved engine power utilization of tractor. The effects of speed ratio (u/v), front gang angle (a), operating depth and cone index (CI) on its draft, torque and power requirement were studied and compared with its traditional passively driven mode at an average soil moisture of 9-10% (db) in sandy-clay loam soil. Optimum system settings were found out before further performance evaluation in the field. The substantially reduced draft requirement with CODH might help to reduce the wheel slippage and improve field productivity while increased power requirement might prevent the under-loading of tractor engine. Tillage quality was assessed considering CI values and found to be far superior compared to traditional mode. Optimum system settings were found at a of 35°and u/v ratio of 3.6 in terms of lowest power expenditure and better work quality with torque power expenditure of 60-70% in total power indicating improved utilization of engine power if operated with tractor power takeoff (PTO).

- by Ganesh Upadhyay
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- Tractor and Farm Equipments, Soil and Tillage, Power Take Off, Torque
- by Fabrizio Mazzetto
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- Mechanical Engineering, Agricultural Engineering, Industrial Design, TRIZ

The performance of a 118-kW tractor fuelled by pure biodiesel was monitored during a long-term field experiment with approximately 800 h of engine function. The objective was to demonstrate that B100, a pure biodiesel fuel, is a viable alternative to traditional diesel oil in terms of long-term mechanical reliability. A bench test on the new engine, performed by attaching a test stand to the power take-off of the tractor, showed an expected reduction in power (-9%) and torque (-7%) and an increase in specific consumption (+13%) when biodiesel was used as a complete substitute to diesel oil. Furthermore, with the same setup, the exhaust gas had a Bosch smoke index equal to 50% of the value for the same engine fuelled with diesel oil. After these initial tests, the tractor was set up for normal field operations, in which both the engine curves and lubricant quality were periodically monitored. These surveys indicated no significant reduction in engine performance; however, the lubricant was consequently diluted and contaminated by biodiesel, which caused the lubricant properties to considerably worsen. However, on the basis of the chemical-physical analysis, reducing the oil change interval from 200 h (manufacturer's indications for the engine when operating with diesel oil) to 100 h would compensate for this progressive quality decline. At the end of the trials, the engine was disassembled to check the condition of its components; wear and lacquer-like coating phenomena were observed, and their levels were acceptable. The obtained results demonstrated that B100 can effectively substitute for diesel oil in a standard compression-ignition engine: the power change is not perceptible during normal operation of a tractor, and no particular problem will arise in the engine during its life if the lubricant is changed every 100 h.

- by Marco Bietresato and +1
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- Agricultural Engineering, Biodiesel, Farm Power and Machinery, IC engine design, bio-fuels, Hybrid EV powertrain design
- by Marco Bietresato and +1
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- Mechanical Engineering, Agricultural Engineering, Geometric Morphometrics, Industrial Design

The effect of biofuel blends on the engine performance and emissions of agricultural machines can be extremely complex to predict even if the properties and the effects of the pure substances in the blends can be sourced from the literature. Indeed, on the one hand, internal combustion engines (ICEs) have a high intrinsic operational complexity; on the other hand, biofuels show antithetic effects on engine performance and present positive or negative interactions that are difficult to determine a priori. This study applies the Response Surface Methodology (RSM), a numerical method typically applied in other disciplines (e.g., industrial engineering) and for other purposes (e.g., setup of production machines), to analyse a large set of experimental data regarding the mechanical and environmental performances of an ICE used to power a farm tractor. The aim is twofold: i) to demonstrate the effectiveness of RSM in quantitatively assessing the effects of biofuels on a complex system like an ICE; ii) to supply easy-to-use correlations for the users to predict the effect of biofuel blends on performance and emissions of tractor engines. The methodology showed good prediction capabilities and yielded interesting outcomes. The effects of biofuel blends and physical fuel parameters were adopted to study the engine performance. Among all possible parameters depending on the fuel mixture, the viscosity of a fuel blend demonstrated a high statistical significance on some system responses directly related to the engine mechanical performances. This parameter can constitute an interesting indirect estimator of the mechanical performances of an engine fuelled with such blend, while it showed poor accuracy in predicting the emissions of the ICE (NO x , CO concentration and opacity of the exhaust gases) due to a higher influence of the chemical composition of the fuel blend on these parameters; rather, the blend composition showed a much higher accuracy in the assessment of the mechanical performance of the ICE.

- by Marco Bietresato
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- Agricultural Engineering, Biodiesel, BIOETHANOL, Response Surface Methodology

Prima di parlare di efficienza delle macchine agricole è necessario fare un po’ di chiarezza sui termini. Quando si parla di quantificazione dell’efficienza di un sistema si intende il calcolo del suo rendimento, inteso come il rapporto matematico tra l’energia utile in uscita al sistema considerato (in qualunque forma essa sia: elettrica, chimica, termica, …) e l’energia in entrata (ancora una volta, in qualunque forma essa sia), espresso con un numero puro (tra 0 e 1) oppure come percentuale. La quantificazione del rendimento non è un’operazione semplice, perché implica un controllo molto preciso dei flussi di energia che attraversano la frontiera del sistema considerato ma è sempre utile, poiché è associata alla bontà delle trasformazioni energetiche che avvengono all’interno del sistema. L’operazione di contabilizzazione del rendimento di un sistema ha un altro risvolto molto interessante, che riguarda la quantificazione della quota parte dell’energia in ingresso che viene dissipata all’interno del sistema sotto forma di calore, e che quindi è fonte di dilatazioni strutturali e possibili surriscaldamenti anche a carico dei sistemi adiacenti.

Solar photovoltaic (PV) systems have shown their potentiality in its usage rural projects around the world. With decreasing continual prices of PV systems, it becomes economically attractive and growing experience gained with the use of PV in the agriculture activities, in turn obtaining a significant impact on rural development. The current work aims to study the performance of PV system [power output, (Poutput), and conversion efficiency, (PV)] to operate a developed standalone an electric solar tractor under two tilt angles of PV panel (0 and 30º). Also, control circuits of brush DC motor based on pulse width modulation (PWM) were designed, manufactured and evaluated. The designed system allows controlling speed of the DC motor in both of forward and reversing direction. The obtained results indicated that, the daily average (Poutput) of PV reaches about 1.95 and 2.15 kWh for 0 and 30º tilt angles, respectively. While the daily average of PV is about 13.2 and 13.3 % for 0 and
30º tilt angles, respectively. These results were corresponding to daily average insolation of 788.89 and 859.33 W/m2 at daily average PV module temperature of 36.2 and 37.4ºC for 0 and 30º, respectively. The experimental setup offers many advantages such as simple structure, low cost, accurate, quite efficient, and light mass. This work is considered as a primary step for the commercial use of a solar powered electric tractor for light service in the agricultural farm.
Keywords: tilt angle; electrical vehicle; solar modules; conversion efficiency, standalone
automated tractor.

- by Ramy Emara
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- Renewable Energy, Autonomous Robotics, Automatic Control, Renewable energy resources

When speaking of quantification of the efficiency of a system, we mean the calculation of its thermodynamic efficiency, defined as the mathematical ratio between the input energy, i.e. the energy entering the considered system (in any of its forms: electric, chemical, thermal …), and the output energy (once more, in any of its forms), expressed with a pure number (between 0 and 1) or as percentage. The quantification of the efficiency is not a simple operation because it implies a very precise control of the energy flows that cross the boundary of the analysed system, but it is always useful as it is associated to the goodness of the energy transformations that occur inside that system. How characterizing the efficiency of agricultural machines A

- by Dario Friso
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- Agricultural Engineering, Environmental Science, Biodiesel, Farm Power and Machinery

In the development of a transportable test-system for the on-site detection of many technical parameters concerning agricultural engines, two concurrent but conflicting needs have to be managed: (1) having a high degree of completeness (and compactness) of the equipment, (2) coordinating the acquisitions from several instruments by using a possibly unique acquisition clock (i.e., with the same time interval and acquisition instant). For the first point, the ideal solution is to have as many test-instruments as possible, however, all transportable with a single vehicle and, possibly, requiring a monophasic 230-VAC power supply (i.e., available in any civil building, including farms); instead, the second point may imply a much higher complexity to be addressed. Despite it, it is possible to select and purchase only instruments with the same type of data-output (e.g., serial), the acquisition rates can be very different, due to the different types of instruments and operating principle...

- by Marco Bietresato
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- Agricultural Engineering, Safety Engineering, Slope Stability, Stability

A microcontroller-based embedded digital display and warning system was developed for measuring wheel slippage, velocity ratio, PTO torque, and draft requirement of active tillage machinery. The hardware system included magnetic pickup sensor for measuring the engine speed, load cells and amplifiers to measure and amplify the sensing unit signals of the draft, proximity sensors for wheel slip, and PTO torque transducer for measuring the torque requirement. It was provided with buzzers and LEDs to warn the operator, whenever slip and velocity ratio were not in the desired range based on the algorithm, for maximum fuel efficiency and tractive performance. It measured slippage, velocity ratio, torque and draft with a maximum absolute variation of 12.90%, 7.92%, 8.99% and 11.57%, respectively. The developed system can be easily adaptable to any combination of tractor and tillage implements, and guide the operator for better soil tilth with lesser energy input.

- by Ganesh Upadhyay and +1
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- Embedded Systems, Tractor, Tractor and Farm Equipments, Digital Displays

Autonomous guidance of agricultural vehiclesis vital as mechanized farming production becomes more prevalent. It is crucial that tractor-trailers are guided with accuracy in both lateral and longitudinal directions, whilst being affected by large disturbance forces, or slips, owing to uncertain and undulating terrain. Successful research has been concentrated on trajectory control which can provide longitudinal and lateral accuracy if the vehicle moves without sliding, and the trailer is passive. In this paper, the problem of robust trajectory tracking along straight and circular paths of a tractor-steerable trailer is addressed. By utilizing a robust combination of backstepping and nonlinear PI control, a robust, nonlinear controller is proposed. For vehicles subjected to sliding, the proposed controller makes the lateral deviations and the orientation errors of the tractor and trailer converge to a neighborhood near the origin. Simulation results are presented to illustrate that the suggested controller ensures precise trajectory tracking in the presence of slip.

Using agricultural machines on slopes is very risky for operators: drivers difficultly have a correct perception of the stability-condition of their vehicles when travelling, especially because it is impossible to instantly check the ground elevation and harshness in correspondence of each wheel. Moreover, the tests that are usually performed to characterize these machines’ stability are scarcely helpful in real conditions: these tests check the lateral overturning (maximum angle) in two static configurations only. Evidently, these do not cover most of real situations, do not locate its centre-of-mass and do not consider the centrifugal force (causing load-transfers and dynamically-variable readjustments of the machine’s trim in turnings), thus making impossible the setup of eventual active/passive safety-systems to be installed on vehicles.
Therefore, with the aim of overcoming the limitations of actual tests, giving a higher level of information to the tractors’ manufacturers and users, we have conceived a completely-new test-apparatus to be installed within our laboratory: the Tiltable Platform. It integrates two subsystems, illustrated hereinafter.
(1) The tiltable/angleable plane is a wide flat structure (15×15 m), able to simulate different ground-gradients, allowing a vehicle to manoeuvre/travel on it along circular paths in a controlled and safe environment. It can also generate an angle at half of its width, transversal to the maximum-slope direction (simulating the exits from interrows).
(2) The tilting turntable: has a circular shape and is divided into quadrants, each capable of measuring the weight sustained due to a motionless vehicle positioned on them; it is installed on a tilting structure and can rotate around a vertical axis, thus allowing to vary the angular position of the vehicle’s longitudinal axis with reference to the maximum-slope direction.
Finally, this test-rig will be useful to develop new test-methodologies to certify the agricultural machines’ stability in real operating-conditions (e.g. operating with ballast/mounted-implements).

- by Fabrizio Mazzetto and +1
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- Agricultural Engineering, Safety Engineering, Slope Stability, Stability

The agricultural tractor is at the center point of agricultural mechanization. Tractor costs have
great influence on
farm business profit. Knowledge of tractor costs for farm operations has a prime importance in
making management plans and decisions especially in comparing different tractor types and models
thereby assisting in the selection of a more appropriate farm tractor. This study reports the
repair and maintenance cost for MF375 tractors with a view to providing such decision making aids
as machine’s replacement and overall farm budgeting for machinery managers. Information on 75 MF375
tractors was obtained through a structured questionnaire. Data collected was sought on tractor
characteristics and economic costs such as use of tractor each year, fuel consumption cost,
lubrication oil cost, oil and fuel filters replacement cost and workmanship cost. Result showed
that the cost of tractor spare parts replacement had the highest percentage share (54.2%) from the
total percentage cost followed by cost of fuel (20.4%), workmanship cost (13.0%), and then cost of
lubrication oil (10.3%) while cost of oil and fuel filter
replacement had the least (2.1%) percentage share.

- by MOHAMMED SHU'AIBU ABUBAKAR and +1
- •
- Tractor and Farm Equipments

Because in some applications the potential exists for tractors to rollover, to reduce the danger to the driver Roll-Over Protective Structures (ROPS) and their corresponding international testing procedures were introduced some time ago. However, some fatalities and serious injuries resulting from rollover accidents still occur. This has led to continuing interest in gaining further understanding of the parameters influencing rollover. The different initial conditions for rollover were analysed and the energy available at the start of rollover evaluated. In particular, the theoretical difference in available energy for lateral rollover on different planes, together with the inclusion of forward velocity, was analysed. Data pertaining to 102 narrow-track tractors fitted with front ROPS, with masses in the range 780–2380 kg were used to calculate the available energy. The results support the hypothesis that there is a non-linear relationship between tractor mass and available energy.

- by Ahmad Sharifi and +2
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- Engineering, Carbon Dioxide, Life Cycle Assessment, Research evaluation

The fuelling of internal combustion engines with biofuels has certainly many environmental and energetic advantages. These advantages are particularly effective in the agricultural sector, where an integrated biofuel supply-chain would further benefit the overall carbon balance. Unfortunately, there are also some drawbacks, mainly concerning the engine performances (lowering of the torque curve), but also environmental (possible raising of the NOx emissions). However, by appropriately mixing two biofuels with known opposite effects on the combustion process, it is theoretically possible to compensate the aforementioned disadvantages. In this work, some experiments were carried out in this direction by fuelling a farm tractor with four different fuel mixes; the collected data were processed through the Response Surface Methodology to obtain multi-parameter regression equations useful to identify the optimal fuel mixtures composition. Thanks to this approach, it was found that biodiesel has a positive effect on the torque, while the addition of bioethanol has a much bigger detrimental effect; on the contrary, bioethanol should be added to a mixture with a minimum of 8-12 % of biodiesel to get advantages in terms of NOx concentration reduction.

- by Marco Bietresato and +1
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- Mechanical Engineering, Biodiesel, BIOETHANOL, Response Surface Methodology

Надежная работа тормозных систем колесных машин оказывает влияние на их устойчивость, что проявляется отсутствием склонности к заносу при торможении и возможностью остановиться за минимально возможное время. Предложен усовершенствованный метод оценки надежности тормозной системы шарнирно-сочлененной колесной машины с использованием метода парциальных ускорений. Рассмотрена схема сил, действующих на шарнирно-сочлененную колесную машину при торможении с незаблокированными колесами, при условии возможного складывания ее секций. Получен критерий в виде углового ускорения в плоскости дороги , по величине и знаку которого можно судить об отказе тормозных механизмов. При торможении с работоспособными тормозными механизмами (стабилизирующее парциальное угловое ускорение будет превышать возмущающее парциальное угловое ускорение) колесная машина будет обладать запасом устойчивости. При достижении машина станет неустойчивой, что может свидетельствовать о неправильной работе тормозной системы. Критерий учитывает современный уровень развития колесных машин, позволяющий создать тормозное управление, в котором распределение тормозных сил между осями осуществляется в соответствии с распределением нормальных реакций дороги. Полученные результаты могут быть использованы при проектировании, производстве и эксплуатации шарнирно-сочлененных колесных машин.

- by Marco Bietresato
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- Agricultural Engineering, Morphometrics, Geometric Morphometrics, Evolution

The safety of agricultural tractors' drivers is a very actual topic, especially when tractors operate on side slopes, such as in terraced vineyards. This work approaches the stability problem of articulated tractors' stability by modelling, simulating and quantifying the safety of the driver with respect to both roll and pitch overturns. First of all, an articulated tractor has been modelled and simplified, after that a stability index has been defined and calculated in several simulated slope conditions when the tractor travels along a circular trajectory then, the obtained results have been compared with respect to a conventional tractor. This work is a preliminary study for a tilting test platform for real vehicles, capable to reproduce real field conditions (slope, obstacles, roughness). Finally, some directives on how exploiting the obtained results for real-time safety devices have been formulated.

- by Fabrizio Mazzetto
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- Agricultural Engineering, Environmental Science, Biodiesel, BIOETHANOL

This study assessed the management of tractor-hiring
entrepreneurship by Tractor Owners and Hiring Facilities
Association of Nigeria (TOHFAN). Two-stage sampling technique
was used to select respondents. A checklist was used in an indepth interview to elicit relevant information which was analyzed
qualitatively. Various models of tractor-hiring operations of
TOHFAN were identified. The loan guarantee system, the tractor
tracking system as well as the business challenges were examined.
Data were collected using a checklist in a focus group discussion
and key informant interview. Findings revealed that TOHFAN
guaranteed loans for its members through collaboration with
relevant financial institutions and vendors. Currently (as at
December 2016), the association operates with 262 tractors and
757 members across 21 states of the country since 13 years of its
establishment. Four distinct models identified were: model involving
hiring agent, model involving booking agent, model involving
TOHFAN as booking agent, and direct owner-farmer transaction.
Tractor tracking device was used to determine the location of each
tractor belonging to members. High and unstable interest rate was
the major challenge confronting TOHFAN’s management of tractorhiring services. This study concludes that TOHFAN’s operational
model is unique and therefore recommends that investors in tractorhiring services should be encouraged (through creation of
awareness by extension agencies) to emulate the TOHFAN
example in tractor-hiring management. Models and operational
strategies used by TOHAN (especially the tracking device) can be
adapted by the public tractor-hiring services in order to ensure
effective tractor-hiring management in Nigeria.

- by Fadlullah ISSA
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- Tractor and Farm Equipments

Featured Application: This study describes the possible outputs of a novel test rig having an inclinable and rotating turntable, illustrating in detail the physical laws governing the phenomena. This rig can be successfully used to test the stability of real-scale vehicles in many operative conditions. Abstract: The stability of agricultural machines, earth-moving machines, snow-compaction machines and, in general, of all vehicles that may operate on sloping terrains is a very important technical feature and should not be underestimated. In fact, it is correlated, above all, to the safety of the operators, but also to the preservation of the structural integrity of these vehicles, to the prosecution of the activities and to the preservation of the economic investment. Although these facts are well-known, the international legislation and technical standards do not yet have a sufficient level of detail to give an all-inclusive quantification of the stability of the vehicle under examination in all its working conditions, e.g., at different inclination angles of the support surface, at different climbing angles of the vehicle on the slope, with different tires and inflating pressures, and on different terrains. Actual standards limit the stability tests to the experimental measurement of the lateral rollover angle only. Furthermore, the realization of unconventional test equipment able to widen the usually-tested scenarios could not be simple, due to the necessary size that such equipment should have (to perform tests not in scale) and to the related difficulties of handling full-scale vehicles. This work illustrates the applications of a new rig for testing the stability of vehicles, able to address all the above-illustrated issues and of possible future adoption to certify the stability performance of machines and perform homologations. This installation, named "rotating platform" or "turntable", has the peculiarity of being able to move the machine positioned on it according to two rotational degrees of freedom: (1) overall inclination of the support plane, (2) rotation of the support plane around an axis perpendicular to the plane. The same installation is also designed to record the weight supported by each wheel of the machine placed on it (by means of four sensorized quadrants), both when the platform is motionless and while the above-described movements of tilt and rotation are being carried out, thus locating precisely the spatial position of the vehicle center of gravity. The presented physical-mathematical models highlight the great potential of this facility, anticipate the outcomes of the recordings that the experimenters will have at disposal when the test rig will be effectively active, and help the future understanding of trends of data, thus maximizing the available information content.

- by Marco Bietresato and +1
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- Agricultural Engineering, Safety Engineering, Slope Stability, Farm Power and Machinery

This study suggests a new concept of technology that is a main element of the system of technological change in society: killer or disruptive technology is a based on new products and/or processes that destroys the usage of established products/processes sold and used. The behavior of killer technologies is operationalized here with a simple model that shows how new technologies substitute old ones. technologies. Several examples illustrate this vital concept for economics of technology that can explain the drivers of technological cycles and technological change in society. Empirical evidence of this theoretical framework is based on data of some example technologies. Theoretical framework and empirical evidence hint at general properties of the behavior of killer technologies: a) killer technology is always associated with some comparable established technology in markets; b) killer technology has a disproportionate growth in relation to victim technology; c) in the long run, killer technology has a series of technological advances of its own resulting from various major and minor innovations to pave the way for the dominance over other established technologies in markets; d) learning via diffusion and diffusion by learning are driving forces underlying the development and adoption of killer technology in turbulent markets. The proposed theoretical framework can explain industrial, economic and social change and support strategies of management of technology for competitive advantage of firms and nations.

- by Mario Coccia
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- Technology, Economics of Innovation, Management of Innovation, Radical Innovation
- by Marco Bietresato
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- Safety Engineering, Occupational Health & Safety, Slope Stability, Stability

A methodological approach for evaluating a priori the stability of agricultural vehicles equipped with different mounted implements and operating on sloping hillsides is shown here. It uses a Matlab simulator in its first phase and, subsequently, the Response Surface Modelling (RSM) to evaluate the coefficients of a set of regression equations able to account for the Type-I and Type-II stability of the whole vehicle (tractor + implement with known dimensions and mass).
The regression equations can give reliable punctual numeric estimations of the minimum value of the Roll Stability Index (RSI) and can verify the existence of a Type-I equilibrium without the need of using the simulator or knowing any detail about the model implemented in it. The same equations can also be used to generate many intuitive graphs (“equilibrium maps”) useful to verify quickly the possible overturning of the vehicle.
A case-study concerning a 4-wheel drive articulated tractor is then presented to show the potential of the approach and how using its tools. The tractor has been studied in three scenarios, differing on where the implement has to be connected to the tractor (1: frontally; 2: frontally-laterally; 3: in the back). After performing a series of simulations, a set of polynomial models (with 6 independent variables) has been created and verified. Then, these models were used, together with the related equilibrium maps, to predict the stability of 8 implements for scenario 1, 7 implements for scenario 2, and 3 implements for scenario 3, evidencing in particular the danger of using a lateral shredder with a mass greater than 245 kg.
The proposed approach and its main outcomes (i.e., the regression equations and the equilibrium maps) can give an effective contribution to the preventive safety of the tractor driver, so it could be useful to integrate it in the homologation procedures for every agricultural vehicle and to include the resulting documentation within the tractor logbook.