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Master of Science / Department of Biological & Agricultural Engineering / Ajay Sharda / In the agriculture industry, in-field efficiency of tractors is critical information for operators and producers. Properly matching tractor to implement using real-world tractor performance characteristics is the primary factor that effects in-field efficiency. Currently, tractor testing is primarily conducted in a controlled lab environment to quantify attributes such as power take-off (PTO) power and fuel consumption. However, in-field quantification of these attributes is necessary to gain a full understanding of the machine’s performance. Therefore, this study was conducted with two primary objectives: 1) develop a data acquisition system to measure real-time tractor performance at varying machine states during field operations, and; 2) evaluate the performance of tractors individually and compared to each other. Studies were conducted to test multiple different sized tractors with varying implements used in a specific crop production cycle; these tractors included two smaller 71 HP machines, a 90 HP and a 100 HP machine. The primary performance comparison goals were to evaluate the performance efficiency differences between a cabin and open station machine of the same size, and to evaluate the differences in performance between two similarly sized machines. A custom data acquisition (DAQ) system developed comprises of a torque sensor, flow meter, and GPS to acquire target performance parameters using a National Instruments cRIO system. The PTO torque sensor and fuel flow meter were tested and validated in a controlled lab using a PTO dynamometer and fuel scale. Validation field studies conducted showed that the DAQ system captured real-time performance parameters; strong correlation was observed between power, speed, and fuel consumption.   Using the real-time data allows for a better understanding of the relationship between machine and implement, as well as a more thorough understanding of the effect of terrain and crop load on fuel consumption and PTO power. The peak torque values through the implement drivetrain and their frequencies coupled with the average breakdown of power consumption by the implement gives the manufacturer and producer the opportunity to modify usage trends or design, respectively. Spatial fuel consumption data on a tractor by tractor basis allows varying machines to be compared directly based on their efficiency. Testing of the two smaller tractors took place on the same day in a uniform field. While the data did not indicate any difference between open station and cabin machines, strong correlation was observed between both operating speed and PTO mode selection and performance efficiency. The testing of the two larger tractors was done on sequential cuts of alfalfa on the same field; to account for this, bales were geotagged and weighed to produce a forage density map. Data from testing yielded two main results; the first being that the fuel consumption rate of each tractor and operation can be accurately predicted using an equation using PTO power and operating speed as variables. The equation that defines the fuel consumption for the swathing operation predicts the fuel consumption within 10% over 75% of the time in both sized machines. Data recorded by the DAQ system yields the information necessary to give the manufacturer a thorough understanding of how machines and implements interact with each other, as well as how external factors effect machine performance.

Made available in DSpace on 2014-06-11T19:31:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2000-04-10Bitstream added on 2014-06-13T20:02:35Z : No. of bitstreams: 1 correa_im_dr_botfca.pdf: 641442 bytes, checksum: 5eb8290b7c610c3221e0e02077f35b69 (MD5) / Os pneus radiais de baixa pressão, constituem uma das propostas tecnológicas para melhorar o contato entre o rodado e o solo, proporcionando melhor desempenho trativo ao trator, porém seu comportamento em condições nacionais é ainda pouco conhecido. Assim, o desempenho operacional de um trator agrícola foi estudado com dois tipos de pneumáticos (diagonal e radial de baixa pressão), com duas pressões de inflação (alta e correta/baixa), em duas condições de superfície do solo (firme e mobilizado), com e sem o acionamento da tração dianteira auxiliar. Os pneus diagonais montados no trator foram: Pirelli 14.9-24 TM 40, 10 lonas, no eixo dianteiro e Pirelli 18.4-34 TM 64/R, 6 lonas, no eixo traseiro. Os pneus radiais de baixa pressão montados no trator foram: Michelin 480/65R24 X M108 TL 124, no eixo dianteiro e Michelin 600/65R34 X M108 TL 142, no eixo traseiro. Os níveis de pressão de inflação alta e correta utilizados nos pneus diagonais foram: 138/151 kPa e 96/110 kPa, respectivamente nos eixos dianteiros e traseiros... / The low pressure radial tires constitute a technologic proposal to improve the tire-soil contact, giving better tractive performance, but your behaviour is not well know. Then, the operational performance of a agricultural tractor was studied with two construction tires types (bias and low pressure radial tire), with two inflation pressure (high and low/correct), in two soil surface condition (firm and soft), with and without the use of mechanical front wheel assist drive. The bias tires mounted on tractor were: Pirelli 14.8-24TM 40, 10 PR, in front axle and 18.4-34 TM 64/R, 6 PR, in rear axle. The low-pressure radial tires mounted on tractor were Michelin 480/65R24 X M108 TL 124, in front axle and Michelin 600/65R34 X M108 TL 142, in rear axle... (Complete abstract click electronic access below)

A successful model for off-road tyres must be reliable, efficient and capable of reproducing and predicting the main system phenomena. Mathematical models are proposed for longitudinal, lateral and combined lateral and longitudinal force generation characteristics of off-road tyres. For a better understanding of off-road tyre behaviour, the study of the interaction between the tyre forces and those generated by the deformed soil is very important. Details of the force system in the contact patch, therefore, are used as a basis for developing models for the prediction of the tractive performance and comering characteristics of off-road tyres. Previous work of the relevant literature pertaining to tyre behaviour is reviewed to provide the reader with background information on off-road tyre characteristics. Various models for off-road tyres of differing degrees of complexity but which all incorporate the key features of off-road tyre problems are then developed. Previous methods of analysing the combined lateral and longitudinal forces generated by off-road tyres on deformable surfaces are investigated. A modified version of a previous model is then proposed which is based on a different and original method for investigating tyre behaviour in the contact region. An entirely new model is then developed which is based on a modification of the "multi-spoke" tyre model used for road vehicle studies. Predicted results are compared with those obtained from other models and with reported experimental data. The usefulness of such models is in problems involving the steering, braking and handling behaviour of off-road vehicles. Hence, the models are formulated so that they can be applied to such vehicle problems by enabling lateral and longitudinal forces on the tyre to be predicted from any combined conditions of wheelslip, wheelskid and slip angle. The proposed models provide an improved qualitative description of behaviour in the contact region. Although slightly more complex than previous models, the computational load is nevertheless sufficiently small that the tyre models can conveniently be incorporated in off-road vehicle handling models. Suggestions for future recommendations are discussed with particular reference to improving the predictive models and for a possible extension of the study to generate more detailed practical results for tyre forces under controlled experimental conditions.

In diploma thesis is general design testing stand during the tractor manufacture, centred on design and calculation main skeleton and strength calculation. Thesis include particular calculation and concrete design parts of measure stand, design and calculation main skeleton, strength calculation, drawing dokumentation of main skeleton and selected parts of measure stand. Thesis also include picture of 3D model whole of measure stand like appended documents.

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Orientador: Kleber Pereira Lanças / Banca: Sergio Hugo Benez / Banca: Carlos Antônio Gamero / Banca: Marcos Milan / Resumo: Os pneus radiais de baixa pressão, constituem uma das propostas tecnológicas para melhorar o contato entre o rodado e o solo, proporcionando melhor desempenho trativo ao trator, porém seu comportamento em condições nacionais é ainda pouco conhecido. Assim, o desempenho operacional de um trator agrícola foi estudado com dois tipos de pneumáticos (diagonal e radial de baixa pressão), com duas pressões de inflação (alta e correta/baixa), em duas condições de superfície do solo (firme e mobilizado), com e sem o acionamento da tração dianteira auxiliar. Os pneus diagonais montados no trator foram: Pirelli 14.9-24 TM 40, 10 lonas, no eixo dianteiro e Pirelli 18.4-34 TM 64/R, 6 lonas, no eixo traseiro. Os pneus radiais de baixa pressão montados no trator foram: Michelin 480/65R24 X M108 TL 124, no eixo dianteiro e Michelin 600/65R34 X M108 TL 142, no eixo traseiro. Os níveis de pressão de inflação alta e correta utilizados nos pneus diagonais foram: 138/151 kPa e 96/110 kPa, respectivamente nos eixos dianteiros e traseiros... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The low pressure radial tires constitute a technologic proposal to improve the tire-soil contact, giving better tractive performance, but your behaviour is not well know. Then, the operational performance of a agricultural tractor was studied with two construction tires types (bias and low pressure radial tire), with two inflation pressure (high and low/correct), in two soil surface condition (firm and soft), with and without the use of mechanical front wheel assist drive. The bias tires mounted on tractor were: Pirelli 14.8-24TM 40, 10 PR, in front axle and 18.4-34 TM 64/R, 6 PR, in rear axle. The low-pressure radial tires mounted on tractor were Michelin 480/65R24 X M108 TL 124, in front axle and Michelin 600/65R34 X M108 TL 142, in rear axle... (Complete abstract click electronic access below) / Doutor

Today’s farmers gut feeling and Fingerspitzengefühl comes from a learning by doing. By year 2025 farmers will have less know-how than today. Foretell supports the farmers in developing their gut feeling and lead more efficient farms. By visualising data, the system provides a comprehensive overview of the farm, both in the tractor, the barn, at the field and in the office. In the transition from running a family farm to become an entrepreneur with an own company has resulted in that the farmers need to supervise the farm’s production but also have control of external conditions. Future farmers needs to quicker become experts. Through research and user studies the system Foretell have been created. Foretell connects the data available today and displays it where it is needed and when it is suitable. The mobile application shows information on the go. While the desktop version gives the user better planning tools. A new precision farming input is added in form of a near-infra-red camera that detects the plants health. With all pieces together Foretell is bringing gut feeling to farmers!

Thesis (PhD) -- University of Alabama, 1997