Trolls: a novel low-cost controlling system platform for walk-behind tractor

A novel low-cost controlling system platform for walk-behind hand tractors (Quick G3000 and G1000) was designed and developed to solve the fatigue problem faced by farmers when ploughing the rice field. This platform is dedicated to designing and manufacturing mechanical, electrical, and software components. The tractor was modified and added with an embedded control system that functioned as the slave, while the direction of the tractor movement was controlled remotely by humans through Bluetooth communication with the smartphone application as the master. Several servos and direct currents (DCs) were used as the actuator to move some levers and clutches instead of the tractor to make it remotely controllable. This system has been directly tested in the paddy farming land through two tractors: Quick G3000 and G1000. The testing results showed that this system could be used within more or less six hours; there is a cost-efficiency of 21.74% and 84.62% battery usage efficiency. More efficient mechanics caused this cost efficiency, and the reduction in electronic devices affects battery efficiency. A low-cost platform for controlling walk-behind tractors has been successfully developed; this platform assists farmers in ploughing their fields

Tractor Measurement and Data Acquisition System for Hydraulic Power, Draft Force, and Power Take-off Torque

Numerous advancements in machinery performance of agricultural tractors have been made in recent years. The Organisation for Economic Co-operation and Development (OECD) tests predetermined points (e.g., maximum power and torque) for drawbar, Power Take-Off (PTO), and hydraulic power as separate tests for tractor performance. Testing methods with the tractor operating at a steady state have been done for years, which were uncharacteristic of agricultural tractor operations in field conditions. As part of this thesis work, field usable data acquisition systems (DAQs) were developed to record implement energy consumption (e.g., drawbar loading, PTO torque, and hydraulic power). The system used LabVIEW software and National Instrument’s compact data acquisition systems (cDAQs) to record data from instrumentation measuring drawbar, PTO, and hydraulic loads. Data were collected and verified in accordance with OECD standards at the Nebraska Tractor Test Lab (NTTL), an official OECD testing facility. Requirements of the systems were: implementation of each system on multiple machines with minor alterations, minimal changes to the tractor, and equivalent data compared to that recorded by the NTTL testing devices and procedures. Manufacturer’s calibration information along with standardized testing equipment used to tune NTTL testing devices were used to verify that the system would provide data in conformance with OECD testing procedures. The hydraulic system was verified with varying hydraulic line curvatures near the sensors that provided data within a 1 percent difference of the actual hydraulic power. Drawbar tests included calibration of a strain gage instrumented drawbar which recorded loads within 0.67 kN of the calibration fixture. Track testing of the drawbar resulted in measured differences of less than 1 kN with the NTTL load car. For PTO measurements, a power take-off calibration was conducted using a commercially available torque transducer. No statistically significant differences were found between the torque values of the PTO transducer and the dynamometer. The differences in torque values ranged from 3 N∙m to 23 N∙m. Advisor: Santosh K. Pitla and Roger M. Ho

Tractor Measurement and Data Acquisition System for Hydraulic Power, Draft Force, and Power Take-off Torque

Numerous advancements in machinery performance of agricultural tractors have been made in recent years. The Organisation for Economic Co-operation and Development (OECD) tests predetermined points (e.g., maximum power and torque) for drawbar, Power Take-Off (PTO), and hydraulic power as separate tests for tractor performance. Testing methods with the tractor operating at a steady state have been done for years, which were uncharacteristic of agricultural tractor operations in field conditions. As part of this thesis work, field usable data acquisition systems (DAQs) were developed to record implement energy consumption (e.g., drawbar loading, PTO torque, and hydraulic power). The system used LabVIEW software and National Instrument’s compact data acquisition systems (cDAQs) to record data from instrumentation measuring drawbar, PTO, and hydraulic loads. Data were collected and verified in accordance with OECD standards at the Nebraska Tractor Test Lab (NTTL), an official OECD testing facility. Requirements of the systems were: implementation of each system on multiple machines with minor alterations, minimal changes to the tractor, and equivalent data compared to that recorded by the NTTL testing devices and procedures. Manufacturer’s calibration information along with standardized testing equipment used to tune NTTL testing devices were used to verify that the system would provide data in conformance with OECD testing procedures. The hydraulic system was verified with varying hydraulic line curvatures near the sensors that provided data within a 1 percent difference of the actual hydraulic power. Drawbar tests included calibration of a strain gage instrumented drawbar which recorded loads within 0.67 kN of the calibration fixture. Track testing of the drawbar resulted in measured differences of less than 1 kN with the NTTL load car. For PTO measurements, a power take-off calibration was conducted using a commercially available torque transducer. No statistically significant differences were found between the torque values of the PTO transducer and the dynamometer. The differences in torque values ranged from 3 N∙m to 23 N∙m. Advisor: Santosh K. Pitla and Roger M. Ho

Reaaliaikaisen mittausmenetelmän kehittäminen renkaan maaperäkontaktin vaikutuksen analysoimiseksi maatalouden maataloustraktorien liikkuvuuteen

Tämän tutkielman tavoitteena oli suunnitella, rakentaa ja testata helposti asennettava ja käytettävä mittauslaitteisto, joka pystyisi mittaamaan reaaliajassa yksinkertaisia suureita, joiden avulla olisi mahdollista arvioida renkaiden ja maaperän välisen kontaktin vaikutusta maataloustraktorien liikkuvuuteen. Kehitetty mittauslaitteisto perustuu Arduino Uno mikrokontrolleriin kytkettyihin kiihtyvyys- ja etäisyys antureihin sekä traktorin väylätietojen lukemiseen. CAN-väylän lukeminen ja tietojen tallentaminen tapahtui RaspberryPi pienoistietokoneeseen liitetyn CAN-väylä kortin avulla. Anturit kalibroitiin ja niiden herkkyys tarkistettiin ennen kokeiden suorittamista peltoajossa. Kiihtyvyysanturit sijoitettiin traktorin taka-akselin päälle molempiin päihin koteloihin ja etäisyysanturit kiinnitettiin akselin takapuolelle. Kaikkia antureita luettiin RaspberryPi:n sarjaporttiin liitetyn Arduinon välityksellä ja tiedot tallennettiin tehdyllä python ohjelmalla. Raspberry Pi valittiin tietokoneeksi sen vähäisen tilavuusvaatimuksen, alhaisen hinnan sekä liitäntöjen monipuolisuuden vuoksi. Pellon ominaisuuksia seurattiin kuukausittain suoritetuilla penetrometri mittauksilla sekä maahan upotetuilla SoilScout antureilla, jotka kertoivat maan kosteuden sekä lämpötilan kyseisessä syvyydessä reaaliajassa. Tämän tarkoituksena oli saada selville pellossa kasvukauden aikana tapahtuvat muutokset, jotka vaikuttaisivat myös traktorin liikkumiskykyyn. Mittaukset onnistuivat hyvin ja tulokset arvioitiin olevan laadultaan luotettavia, joten ne tarjoavat monia muita mahdollisuuksia tulevaisuudessa. Tulokset osoittivat selvästi traktorin liikkuvuuteen vaikuttavat tekijät ja maanmuokkauksen eri vaiheet pystyttiin havainnoimaan. Tulevaisuuden haasteina säilyvät edelleen suuren tietomäärän suodattaminen sekä mittauslaitteiden soveltaminen jatkotutkimuksissa. Työssä kehitetty mittauslaitteisto soveltuu tarkoitukseensa mittaustarkkuuden sekä kustannustehokkuutensa puolesta hyvin. Tulevaisuudessa parempaan tarkkuuteen voitaisiin päästä tarkemmilla mittalaitteilla sekä tämän työn pohjalta saaduilla tiedoilla.The purpose of this thesis was to design, build and test a system, which is capable of measuring in real time simple quantities influencing on tire-soil contact of agricultural tractors mobility. The measuring equipment is based on acceleration and distance sensors connected to the Arduino Uno microcontroller. The tractor’s CAN bus was logged and the data was saved using a CAN bus card connected to a Raspberry Pi minicomputer. The sensors were calibrated, and their sensitivity checked before performing the experiments while driving in the field. Accelerometers were placed on top of the rear axle of the tractor at both ends in housings printed for them and distance sensors were mounted behind the rear axle. All sensors were logged by using Raspberry's Raspbian operating system with a python program. The Raspberry was chosen as a computer because of its demanding low space, low cost, and versatility of interfaces. The properties of the field were monitored by monthly penetrometer measurements as well as SoilScout sensors embedded in the ground, which indicated the moisture and temperature of the ground at that depth in real time. The purpose of this was to find out the changes in the field during the growing season, which would also affect the tractor's mobility. The measurement were carried out successfully and the result were considered to be reliable and provide many other opportunities for the future. The results clearly indicated the factors influencing the tractor’s mobility and the different stages of the tillage could be recognized. Future challenges remain the filtering of large amounts of data and the application of measuring equipment in further research. The measurement equipment developed in the work is well suited for its purpose in terms of measurement accuracy and economical affordability. In the future, better accuracy could be achieved with more accurate measuring devices as well as data obtained from this work

Development and Evaluation of Automated Slip and Draft Control System for Tractor

254-261A microcontroller-based Automatic Slip Control System (ASCS) and Automatic Draft Control System (ADCS) for 2WD tractors was devised to automatically alter the depth of operation to keep the wheel slip and implement draft within a prespecified range. An electro hydraulic lift link system was devised to control the depth of the implement's operation. The technology continuously checks wheel slip and draft in the field and notifies the hydraulic system, which changes the implement's depth if the wheel slip and draft exceeds the specified range. Experiments were conducted with defined slip ranges of 10–15, 15–20, and 20–25% for ploughing and cultivating activities. Field capacity and drawbar specific fuel consumption were measured as performance criteria. With the ASCS, the slip was found to range from 15–24%, versus the desired range of 15–20%, while with the current draft control system, it was found to range from 12–48% Tractor Draft Control System (TDCS). Fuel consumption was determined to be 20.13, 21.11, and 22.98 l/ha for ploughing operations with TDCS at initial depth settings of 150, 180, and 220 mm, respectively. However, ASCS resulted in a significant increase in fuel efficiency, with an 11.2% reduction in consumption. When compared to the TDCS, it consumed 4 to 14% less fuel during ploughing operations. Field capacity was increased by 3.4–14.5% due to ASCS and ADCS. The measuring efficiency of the devised system was determined to be greater than 99%

Tractor instrumentation for monitoring energy inputs to implements

A 100-pto-horsepower agricultural tractor was instrumented with a microcomputer-based data acquisition system for monitoring energy inputs to implements powered by the tractor. The data acquisition system included instrumentation for measuring and recording fuel consumption, implement draft, travel speed, angular velocity of each drive wheel axle, and torque on each drive axle. Drive wheel slip, fuel consumption per unit time and area, drawbar horsepower, axle horsepower, tractive efficiency, and implement energy requirement per unit area could be subsequently computed from these measurements. The data acquisition system was installed on a 2675 Massey- Ferguson (two-wheel drive) tractor. The system was centered around a DEC PDP11/03-LK microcomputer that was installed in a rack above the head of the operator. A DEC TU58 cassette tape system, which incorporated dual tape drives, was used for system program and data storage. Communication between the operator and data acquisition system was through a 64-key keyboard and a compact CRT unit for external monitoring of program execution and data display. Other components of the data-handling system included a microprocessor counter box for summing digital signals and a strain gauge signal conditioner/amplifier. All electronic data handling components were mounted within the confines of the tractor cab. The sensing hardware on the instrumented tractor consisted of a fuel transducer and display, a three-point hitch drawbar dynamometer, a free-rolling fifth wheel to indicate travel speed, axle speed indicators, and axle torque sensors. Power for the data handling equipment and sensing transducers was supplied by a portable gasoline generator mounted on the front of the tractor. The instrumented tractor was used during two cropping seasons to measure energy inputs to selected tillage and planting implements. Implements included a subsoiler, chisel plow, heavy tandem disk harrow, light tandem disk harrow, soil pulverizer, cultimulcher, row-crop planter, and no-till row-crop planter. Implements were operated to simulate the cultural practices associated with conventional seedbed preparation and planting. The procedure for data collection consisted of operating a given implement with the instrumented tractor over measured 200-ft plots. The data acquisition system sampled and recorded the monitored parameters at one-second intervals during the test run. Each of the implements, except the subsoiler and row-crop planter, were operated at three travel speeds to obtain a range of energy requirements associated with implement operation. Field data were reduced by averaging numerous test replications of each operating speed-implement combination to obtain mean values for the desired energy-related parameters. The data acquisition system performed satisfactorily with some modifications. Results of the field measurements indicated that the drawbar pull, drawbar power, drive wheel slip, fuel consumption per unit time, and the energy input per unit area processed all tended to increase for each implement as the travel speed was increased. However, the quantity of fuel required to process a unit area tended to decrease slightly for a given implement as the travel speed was increased

Improving path-tracking performance of an articulated tractor-trailer system using a non-linear kinematic model

This paper presents a novel non-linear mathematical model of an articulated tractor-trailer system that can be used, in combination with receding horizon techniques, to improve the performance of path tracking tasks of articulated systems. Due to its dual steering mechanisms, this type of vehicle can be very useful in precision agriculture, particularly for seeding, spraying and harvesting in small fields. The articulated tractor-trailer system model was embedded within a non-linear model predictive controller and the trailer position was monitored. When the kinematic of the trailer was considered, the deviation of trailer's position was reduced substantially alongside not only straight paths but also in headland turns. Using the proposed mathematical model, we were able to control the trailer's position itself rather than the tractor's position. The Robot Operating System (ROS) framework and Gazebo simulator were used to perform realistic simulations examples.Fil: Murillo, Marina Hebe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; ArgentinaFil: Sánchez, G.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; ArgentinaFil: Deniz, Nestor Nahuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; ArgentinaFil: Genzelis, Lucas Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; ArgentinaFil: Giovanini, Leonardo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; Argentin

DEVELOPMENT AND EVALUATION OF A CONTROLLER AREA NETWORK BASED AUTONOMOUS VEHICLE

Through the work of researchers and the development of commercially availableproducts, automated guidance has become a viable option for agricultural producers.Some of the limitations of commercially available technologies are that they onlyautomate one function of the agricultural vehicle and that the systems are proprietary toa single machine model.The objective of this project was to evaluate a controller area network (CAN bus)as the basis of an automated guidance system. The prototype system utilized severalmicrocontroller-driven nodes to act as control points along a system wide CAN bus.Messages were transferred to the steering, transmission, and hitch control nodes from atask computer. The task computer utilized global positioning system data to determinethe appropriate control commands.Infield testing demonstrated that each of the control nodes could be controlledsimultaneously over the CAN bus. Results showed that the task computer adequatelyapplied a feedback control model to the system and achieved guidance accuracy levelswell within the range sought. Testing also demonstrated the system\u27s ability tocomplete normal field operations such as headland turning and implement control

From Hierarchies to Markets: FedEx Drivers and the Work contract as Institutional Marker

Judges are often called upon today to determine whether certain workers are “employees” or “independent contractors.” The distinction is important, because only employees have rights under most statutes regulating work, including wage and hour, anti-discrimination, and collective bargaining law. Too often judges exclude workers from statutory protection who resemble what legal scholars have described as typical, industrial employees — long-term, full-time workers with set wages and routinized responsibilities within a large firm. To explain how courts reach these counterintuitive results, the article examines recent federal decisions finding that FedEx delivery drivers are independent contractors rather than employees. It argues that the problem is embedded within the employment contract itself, in the law’s attempt to construe the legal relations of master and servant as a contract. The contemporary employment contract is product of a 19th century incorporation of master-servant authority into contracts for labor services. In the face of institutional disruption, the contradiction within employment between contractual equality and servitude tends to surface in the form of two doctrinal ambiguities. Both make the dominant standard for employment status irresolvable by merging contractual formation and performance. First, the attempt to fit master-servant authority in the framework of contract creates an ambiguity between the activities of bargaining over the work and carrying out the work, or between contracting and producing. Second, it makes ambiguous the relationship between a written agreement and contractual duties. The way in which FedEx organized the drivers’ work manipulated these ambiguities, which enabled the courts to maintain that features of the work that ordinarily, and under the governing legal tests, would be evidence of employment were here consistent with, or even evidence of, independent contracting. In fact, the courts transform some of the same vulnerabilities that place the drivers within the policy concerns of collective bargaining and wage and hour law into evidence of their autonomy. The attempt to encase master-servant relations in contract also destabilizes distinctions between firms and markets. The ambiguity in employment between contracting and producing exposes a tension within major economic theories of the firm: employment is the legal rationale for a firm’s centralized control over indirect, hierarchical, and multilateral relations in production; as a contract, however, employment is a direct and bilateral relationship between equal parties in a market. The FedEx decisions marshal this tension to redefine a firm, as conceptualized by major theories of the firm, as a market. Multilateral relations among drivers as they work under FedEx’s direction appear as bilateral contracts between drivers in a decentralized market. The courts conflate the impersonality of bureaucracy — in which work is embedded in sophisticated technology and a supervisory hierarchy — with the impersonality of the market. The drivers’ very fungibility as low-skilled workers performing standardized routines becomes evidence of their entrepreneurial opportunity. The article hypothesizes that the invisibility of logistics and communications technology, relative to the heavy machinery of industrial manufacturing, helped the courts to submerge the FedEx bureaucracy beneath a nexus of contracts. It critiques the decisions for rejecting theories of the firm that ground the legitimacy of the corporation in the efficient production of goods and services. The article concludes with a thought experiment showing how, using the arguments in the FedEx decisions, one could reinterpret assembly line employment as independent contracting