Tractor Research Articles

A learning-based memetic algorithm for a cooperative task allocation problem of multiple unmanned aerial vehicles in smart agriculture

Smart agriculture aligns with the principles of sustainable development, making it a crucial direction for the future agriculture. This study focuses on a cooperative plant protection task allocation problem (CPPTAP) of multiple unmanned aerial vehicles (UAVs) with a common deadline in smart agriculture. CPPTAP permits multiple UAVs to conduct pesticide spraying on the same field. The completion time for each task fluctuates due to the cooperation among UAVs. We present a mathematical model and learning-based memetic algorithm (L-MA) to maximize the total area of the fields to be sprayed. In the evolutionary stage, mutation and repair operators based on value information are applied to balance the exploration and exploitation, while a problem-specific local search strategy is designed to enhance exploitation capability. A knowledge-based UAV allocation method (KUAM) is employed to maximize UAV utilization efficiency and minimize conflicts. Throughout the search process, Q-learning is utilized to assist the aforementioned operators and make decisions on the number of cooperative UAVs on fields. The effectiveness of L-MA is validated by comparing it against other state-of-the-art algorithms. The results demonstrate that L-MA outperforms the compared algorithms at a considerable margin in a statistical sense.

Assessment of the impact of agricultural tractor wheels on soil compaction

Abstract This article presents the results of an experimental study on the impact of leading wheel tires 15.5R38 and 16.9R38 on soil. Specifically, the study analyzed the influence of vertical load on the maximum tire pressure (MTA) and internal air pressure on soil. The variations in maximum soil pressures of 15.5R38 and 16.9R38 tires at different internal air pressures depending on corresponding loads were investigated. The characteristics of changes in permissible pressure and loading of tires on soil are graphically depicted, and the permissible standards for their use in agricultural work are determined. Recommendations are provided for using tires at the minimum and maximum permissible internal air pressures. Using values smaller than the recommended values can lead to a decrease in the useful life of the tire.

Development of an Anti-rollover Warning and Active Intervention Controller for Wheeled Tractor

Background: Tractor rollover accidents are the most severe problem in agricultural production. According to the statistical analysis of the rollover incidents, some rollover accidents can be avoided by timely anti-rollover warning and active control. There are a few researches on the anti-rollover control for agricultural tractors, although great progress in the research on tractor security has been achieved, such as rollover protective structure design. Objective: The purpose of this patent study was to develop a controller with the function of warning as well as active anti-rollover control employing the power motor installed on the steering column to adjust the front wheel angle and control the rollover index within the safety range. Methodology: The structure block for the hardware of the controller was devised that included data obtaining, rollover risk estimation, rollover warning, and front-wheel steering control sections. The main circuits have been designed in detail by adopting module methods, such as motor control circuit, positioning and transmission circuit, etc. The control scheme has been demonstrated by designing an overview of the overall architecture, including rollover indicator calculation, load transfer ratio (LTR) controller design, and front-wheel steering angle tracking controller design. C language has been used to accomplish the software design. Results: The active anti-rollover controller can calculate and keep the LTR within the stable range by adjusting the front wheel angle in real-time. The fast response and smoothness of the results demonstrate that the controller can fulfill the designed function. Conclusion: The developed controller can meet the control requirement due to several advantageous aspects, such as reliability, effectiveness, and practicability. It is prospective for the developed controller to provide a valuable reference to reduce tractor rollover accidents.

Use of wide-width tractor units in cotton growing

Abstract The article provides information on recommended traction and power balances of a cotton tractor used in sowing and cultivating 8 rows in growing of cotton seeded at 60 cm row spacing. The purpose of the research is to solve problem of aggregation of sowing and cotton cultivators with four-wheeled tractors and increase their operational-technological and technical-economic performance. According to it, conditions for aggregation of processing units with a tractor are given. The results of scientific and practical research and testing to determine and evaluate performance of machine-tractor units consisting of inter row spacing sowing and cultivators with four-wheel tractors were obtained and analyzed. The dynamics of a tractor in which all bridges are leading and moving forward at a constant speed along a sloping plane are studied. The result is traction balance equation that represents the total traction force of tractor. In particular, the issue of selection and rational aggregation of a tractor model that can be rationally aggregated with a Case-1200 pneumatic seeder has been resolved. It is determined the range of changes the traction resistance and power required to overcome it, the operating weight of tractor, mass and effective power of the Case-1200 seeder.

New Hydraulic Control Technologies for Improving the Energy Efficiency of the Hydraulic System of Agricultural Tractors and Their Implements

New Hydraulic Control Technologies for Improving the Energy Efficiency of the Hydraulic System of Agricultural Tractors and Their Implements

Agricultural Tractor Test: A Bibliometric Review

Agricultural tractors are an essential agricultural power source. Therefore, the scientific literature tests have described agricultural tractors’ evolution over time and determined future trends. This paper uses bibliometric tools to assess the agricultural evolution of tractor testing from 1969 to 2022 to ascertain the publication’s scientific perspective on operational, ergonomic, and energy performance. We searched for relevant research in the Scopus and Web of Science (WOS) databases. The data were processed in RStudio software version 4.4.1, and we used elaborated bibliometric maps to research evolution, major journals, studies, countries, and keywords. The first research mainly concerned the development of new wheelsets, more efficient engines, and fuel consumption prediction models. After the 2000s, environmental protocols contributed to increasing publications on biofuels and renewable energies. Recently, an intense process of robotization in autonomous vehicles has improved to allow the replacement of combustion engines. Ergonomics and safety have been less recurrent topics in recent years, indicating a stable level in the actual research. New machine control models involving artificial intelligence are currently applied to obtain test results without using the machine in the field. These virtual models reduce costs and optimize resources. The most common terms were “tractor” and “agricultural machinery”. The terms “Electric tractor”, “agricultural robots”, and “Matlab” indicate solid trends for future research.

Determine and Analyze the Total Fuel Consumption of an Agricultural Tractor Using Different Plows

Determine and Analyze the Total Fuel Consumption of an Agricultural Tractor Using Different Plows

Determinants of agricultural tractor selection - assessment from the perspective of a supplier of vehicles and means of transport used in agriculture

The subject of the research described in the presented study are the determinants of the selection of agricultural tractors. The research was conducted from the perspective of suppliers of vehicles and means of transport used in agriculture. Its fundamental aim was an attempt to answer the question concerning factors that are crucial from the buyer's perspective and determine their decision to choose a specific tractor. Achieving the main goal required identifying and defining factors conditioning the decision-making process (the multi-criteria model), which was validated later in the study (the assessment of the significance of requirements). Such an approach enabled conclusions and recommendations regarding the method and direction of improvement in the range of offered tractors and related logistic customer service processes. The main burden of the study fell on desk research analysis including the overview of available literature and documentation sources as well as an expert debate (the method of competent judges). In order to transfer the issue to the level of the agricultural machinery sector - through an interview among a deliberately selected group of suppliers of vehicles and means of transport used in agriculture (including New Holland, Claas, Fendt, John Deer, Kubota, Deutz Fahr, Case IH, Massey Ferguson, Zetor, Farmtrac Tractors Europe) – the importance of determinants was clarified (the hierarchy of importance).

Evaluating small‐scale harvesting disturbance to the forest soil in Mediterranean beech high forests

AbstractEuropean beech (Fagus sylvatica L.) forests in Central and Southern Italy are managed applying the shelterwood system. Prior to the regeneration cut, it is common to apply 2–3 thinning interventions, aiming to obtain mostly firewood, considering the low dimension and poor quality of the stems. These interventions are usually carried out by local forest enterprises relying on a low or medium level of mechanization (small‐scale forestry). In particular, the short wood system is applied, thus processing the logs to 1 m length and extracting them with forestry‐fitted farm tractors equipped with forwarding bins. Despite the large application of this harvesting system in the Mediterranean forestry, no information is available in the literature about its possible disturbance to the forest soil. To fulfill this knowledge gap, we developed the first assessment of soil physicochemical (bulk density, penetration resistance, shear resistance, organic matter content) and biological (soil microarthropods biodiversity evaluated with the QBS‐ar index, that is, an index based on the idea that high‐quality soils have more groups of microarthropods that are morphologically better adapted to the soil than low‐quality soils) properties for this kind of logging operation. In three case study areas in Central Italy, we applied an experimental design to evaluate separately the impacts related to the passage of the machine and that of the silvicultural treatment itself. We further applied linear mixed‐effect models to investigate the relationship between changes in soil physicochemical and biological properties. We found the effect of the silvicultural treatment to be negligible, but there was a significant alteration of the investigated parameters in the soil affected by the passage of the machine. Soil penetration and shear resistance doubled in the forwarding trails (0.25 MPa and 4.02 t m−2, respectively) in comparison with the other two experimental treatments (control area and soil not affected by the machine passage; about 0.12 MPa and 2.10 t m−2, respectively). Soil organic matter and soil microarthropod biodiversity (QBS‐ar index) were reduced by 25% in the forwarding trails (about 30% and 92 respectively) in comparison with the soil not affected by the machine passage (about 39% and about 130, respectively). Such significant disturbance, which occurred even if the applied machinery had lower weight in comparison to other alternatives (forwarders), is related to the high number of machine passes needed to extract the woody material with forwarding bins applying the short wood system. We found a significant relationship between soil compaction and soil organic matter removal and microarthropod biodiversity, with the latter which resulted significantly lower in more compacted and organic matter‐poor soils. We demonstrated that this small‐scale extraction system can have a negative effect on soil features in the short term. We therefore recommend the application of best management practices, for instance placing brush mats and logging residues, on the forwarding trails to limit the soil disturbance within the framework of small‐scale forestry. We further recommend a wider application of aerial harvesting systems, which generally have lower impacts to the soil. However, this could happen only after an extensive training program aimed to increase the knowledge and skills of local loggers about aerial harvesting systems.

The Integration of Mechanical Energy Absorbers into Rollover Protective Structures to Improve the Safety of Agricultural Tractors in the Event of Rollover

The combination of safety belts and rollover protective structures (ROPSs) is key in improving the safety of agricultural tractors in the event of rollover. However, we also have the opportunity to enhance the security provided by each ROPS; one such example is the combination of this safety device with adequate mechanical energy absorbers (MEAs). Inexpensive disc-shaped MEAs can be included in the anchoring points of a ROPS onto the chassis of a tractor. Three configurations of ROPS combined with MEAs were tested during the application of loads that simulated the effects of side rollover in the vehicle. The tested configurations included a blank MEA as a reference case alongside a single MEA and a stack assembly containing both elements. The results of the tests show that both the deformation of the ROPS itself and the strain energy are larger in the case of blank MEAs; thus, there is also a risk that the clearance zone will be infringed upon and that the protective structure will collapse. We can conclude that the implementation of an appropriate MEA in ROPS reduces the deformation of the ROPS itself and its strain energy in cases of vehicle rollover; hence, the safety provided by such protection systems may be improved at a low cost.

A curved path extraction method using RGB-D multimodal data for single-edge guided navigation in irregularly shaped fields

Due to the undulating topography, the world contains numerous irregularly shaped small fields. Autonomous navigation along the curved edges of these fields is crucial for achieving complete unmanned operation in these small-field environments. Based on this, we proposed an accurate and robust curved path extraction method using RGB-D multimodal data for single-edge guided navigation in irregularly shaped fields. Leveraging the significant height difference between headland and farmland, we employed an efficient RGB-D multimodal semantic segmentation network to achieve high-precision segmentation of headland area. Meanwhile, a slope-based feature points adaptive selection algorithm and a feature points transformation algorithm fusing multimodal depth data were proposed innovatively for curved navigation path extraction. By utilizing the RGB-D segmentation model ESANet, we achieved a mean intersection over union (mIoU) of 96.94 %, surpassing other RGB segmentation models. The mean deviations between the ground truth path and the extracted path were less than 6.43 pixels on an image with a resolution of 640 × 480. The proposed method can finally achieve a processing efficiency of 23.80 FPS on images in 640 × 480 resolution, and the field experiments tested that the mean deviations of the agricultural vehicle navigating along the extracted curved navigation path were less than 0.188 m, which met the real-time performance requirement and accuracy requirement of autonomous navigation.

РАЗРАБОТКА ИНДИКАТОРА ОЦЕНКИ ТЕХНИЧЕСКОГО СОСТОЯНИЯ КОРОБОК ПЕРЕДАЧ

The efficiency of the use of high-energy tractors in agriculture is largely determined by the level of preparation for field work, which in turn depends on the completeness of the repair and maintenance work. Various diagnostic tools are used for a non-selective assessment of the general technical condition of internal combustion engines: motor testers, crankcase gas flow meters, etc. Currently, there are no means to assess the technical condition of the gearbox without breaking the power flow. The development of digital diagnostic tools is required to reduce the risk of failures during field work. (Research purpose) The research purpose is studying the state of the issue and justifying the need to develop a coefficient for a non-selective assessment of the general technical condition of the hydraulic transmission control drive of high-energy tractors. (Materials and methods) Carried out an analysis of the complex of works on diagnosing and managing the reliability of agricultural machinery. It was found that it is necessary to control the time of the transient process in the hydraulic control system of the gearbox, as well as accelerations during gear shifting. We reviewed the previously manufactured control and diagnostic equipment. The KI-12383 and "Effect-02.01" devices were chosen as a prototype for the development of a digital indicator. (Results and discussion) We conducted a simulation, designed and tested a prototype and proved the possibility of developing a digital indicator that can be used as an integrated diagnostic tool to justify the need for repair and maintenance effects of the gearbox. (Conclusions) To monitor the general technical condition of the gearbox, a digital indicator is needed, which will allow, without making changes to the design (K-701, T-150K and their modern analogues), to obtain diagnostic data to substantiate repair and maintenance impacts in order to reduce the risks of failures of the III complexity group during field work.

Autonomous Driving Strategy for a Specialized Four-Wheel Differential-Drive Agricultural Rover

Recently, the agriconstruction machinery sector has been involved in a great technological revolution. The reasons that may explain this are strictly connected to the mitigation of climate change. At the same time, there is a necessity to ensure an adequate production level in order to meet the increasing food demand due to the current population growth trend. In this context, the development of autonomously driven agricultural vehicles is one of the areas on which tractor manufacturers and academics are focusing. The fundamental prerequisite for an autonomous driving vehicle is the development of an appropriate motion strategy. Hence, the vehicle will be able to follow predetermined routes, accomplishing its missions. The aim of this study was the development of path-planning and path-following algorithms for an agricultural four-whee differential-drive vehicle operating in vineyard/orchard environments. The algorithms were completely developed within the MATLAB software environment. After a brief description of the geometrical characteristics of the vehicle, a parametric process to build a virtual orchard environment is proposed. Then, the functional principles of the autonomous driving algorithms are shown. Finally, the algorithms are tested, varying their main tuning parameters, and an indicator to quantify the algorithms’ efficiency, named relative accuracy, is defined. The results obtained show the strong dependence between the relative accuracy and lookahead distance value assigned to the rover. Furthermore, an analysis of rover positioning errors was performed. The results in this case show a lower influence of the location error when the accuracy of the positioning device is within 2 cm.

Controlled Traffic Farm: Fuel Demand and Carbon Emissions in Soybean Sowing

Soil compaction between crop rows can increase a machine’s performance by reducing rolling resistance and fuel demand. Controlled Traffic Farm (CTF) stands out among modern techniques for increasing agricultural sustainability because the machines continuously travel along the same path in the field, reducing plant crush and compacting the soil in the traffic line. This study evaluated fuel consumption and CO2 emissions at different CTF intensities in different soil management strategies for soybean crop. The experimental design involved randomized blocks in a split-plot scheme with four replications. The plots constituted the three types of soil management: conventional tillage, no-tillage with straw millet cover, and no-tillage with brachiária straw cover. The subplots constituted for agricultural tractors were passed over in traffic lines (2, 4, and 8 times). We evaluated agricultural tractor fuel consumption, CO2 emissions, and soybean productivity. The straw cover and tractor-pass significantly affected the fuel consumption and greenhouse gas emissions of the soybean cultivation. Fuel consumption and CO2 emissions were reduced due to the machine-pass increase, regardless of soil management. Thus, a CTF reduces rolling resistance and increases crop environmental efficiency. Bare-soil areas increased by 20.8% and 27.9% with respect to fuel consumption, compared to straw-cover systems. Brachiária straw and millet reduce CO2 emissions per hectare by 20% and 28% compared to bare soil. Lower traffic intensities (two passes) showed (13.72%) higher soybean yields (of 4.04 Mg ha−1). Investigating these effects in other types of soil and mechanized operations then becomes essential.

Tractor Three-Point Hitch Control for an Independent Lower Arms System

The three-point hitch, found on agricultural tractors, facilitates the raising and lowering of an attached implement. Some tractors include a rock shaft that comprises a physical shaft that interconnects and facilitates the raising and lowering of the lower arms of the three-point hitch in a synchronized manner. In this study, we deal with a hitch system with the lower arms actuated by two independent hydraulic cylinders. This innovative tractor hitch system design allows the implement to follow the terrain, instead of the tractor, about the fore–aft (roll) axis of the tractor. However, since the two lower arms are independent, a specialized controller is needed to move these arms in unison. First, we present a position controller for individual arms and a roll controller to move these arms together. Second, we present a unique algorithm to emulate a physical rock shaft while the implement is operating in float mode. The algorithm ensures that the implement does not roll around the fore–aft axis while making sure it moves up and down vertically to follow the terrain. We present experimental results from the step response of the hitch system’s height while tracking a velocity reference. With the roll of the implement defined as the difference between the left arm’s position in percentage and that of the right arm in percentage, we observe that the largest mean roll was 0.23% with a flail mower attached and 0.26% without any implement. We then present results from the implement’s position in the float mode when the software rock shaft was activated and compare them with the case without the software rock shaft. The experiments showed that, when the software rock shaft was turned on, the mean roll reduced from 4.64% to 0.58% with a seed drill implement and from −3.99% to −0.59% with a flail mower implement. The standard deviations in these two implement cases improved from 16.77% to 2.79% and 6.45% to 3.53%, respectively, proving the effectiveness of the software rock shaft and its potential to replace the physical rock shaft found on the traditional tractors.

Experimental validation of a predictive energy management strategy for agricultural fuel cell electric tractors

Efficiency and durability are critical challenges for the large-scale adoption of fuel cell powertrains in agricultural tractors due to the demanding nature of farm-related tasks. This study presents a novel predictive energy management strategy that uses forecasts of the average load of the farming cycle to achieve stationary fuel cell operation, thus limiting degradation caused by load cycling, high-power, and low-power operation. The recurrent characteristics exhibited by agricultural duty cycles allow the calculation of highly accurate average load prediction, which can be sufficient for a predictive energy management strategy to reduce degradation without hindering fuel consumption. As a result, this forecast is utilized in conjunction with a straightforward and real-time-capable energy management strategy, which foresees the operation of the fuel cell system at the level of the average load. The work is structured into two main contributions: model-based design of the energy management strategy, and experimental validation on a fuel cell powertrain testbed. Three typical agricultural duty cycles were studied to evaluate the benefits of the proposed strategy, demonstrating that energy management strategies can mitigate fuel cell degradation without compromising system efficiency. In particular, the predictive energy management strategy offers the potential to mitigate the negative impact of tractor operational idling time at the headland turns through the reduction of fuel consumption, thereby enhancing overall tractor performance. The experimental powertrain setup stands as an innovative contribution within the research landscape concerning fuel cell powertrains for tractors and validates the benefits of the proposed strategy. Furthermore, the conducted testbed analyses assume significance in highlighting the effects of the energy management strategy on the physical fuel cell operating factors and emphasizing the comprehensive benefits across the powertrain system, particularly with regard to the thermal management of the fuel cell system, where the prevention of derating is achievable through the implementation of the proposed energy management approach. Overall, the findings of this study have important implications for the development of sustainable and efficient farming procedures through the adoption of fuel cell technology in agricultural machinery.

Load analysis of the electrical system of an agricultural tractor with EZ-Pilot parallel driving system and CFX-750 panel from TRIMBLE

Load analysis of the electrical system of an agricultural tractor with EZ-Pilot parallel driving system and CFX-750 panel from TRIMBLE

Optimization‐based motion planning for autonomous agricultural vehicles turning in constrained headlands

AbstractHeadland maneuvering is a crucial part of the field operations performed by autonomous agricultural vehicles (AAVs). While motion planning for headland turning in open fields has been extensively studied and integrated into commercial autoguidance systems, the existing methods primarily address scenarios with ample headland space and thus may not work in more constrained headland geometries. Commercial orchards often contain narrow and irregularly shaped headlands, which may include static obstacles, rendering the task of planning a smooth and collision‐free turning trajectory difficult. To address this challenge, we propose an optimization‐based motion planning algorithm for headland turning under geometrical constraints imposed by headland geometry and obstacles. Our method models the headland and the AAV using convex polytopes as geometric primitives, and calculates optimal and collision‐free turning trajectories in two stages. In the first stage, a coarse path is generated using either a classical pattern‐based turning method or a directional graph‐guided hybrid A* algorithm, depending on the complexity of the headland geometry. The second stage refines this coarse path by feeding it into a numerical optimizer, which considers the vehicle's kinematic, control, and collision‐avoidance constraints to produce a feasible and smooth trajectory. We demonstrate the effectiveness of our algorithm by comparing it to the classical pattern‐based method in various types of headlands. The results show that our optimization‐based planner outperforms the classical planner in generating collision‐free turning trajectories inside constrained headland spaces. Additionally, the trajectories generated by our planner respect the kinematic and control limits of the vehicle and, hence, are easier for a path‐tracking controller to follow. In conclusion, our proposed approach successfully addresses complex motion planning problems in constrained headlands, making it a valuable contribution to the autonomous operation of AAVs, particularly in real‐world orchard environments.

Factors Affecting the Farmer’s Use of Modern Irrigation Systems in Northern Aleppo

This study investigates the adoption of modern irrigation methods, specifically sprinkler and drip irrigation, among farmers in northern Aleppo, Syria. Through a sample of 210 farmers selected via random sampling, we analyze how socio-demographic, geographic, and socio-economic factors impacting the adoption of modern irrigation methods. Using the chi-square test of independence, we compared users and non-users of modern irrigation systems to discern significant disparities across various characteristics. Our findings indicate the use of modern irrigation methods is influenced by various factors in northern Aleppo. These include the educational level of the farmers, the number of years of experience in agriculture, the size of the family, the slope of the land, the distance of the land from surface water sources, the size of the farm, the source of labor, ownership of an agricultural tractor, and the prices of agricultural inputs. In light of these insights, we propose targeted interventions by local authorities and agricultural extension organizations to promote modern irrigation methods in collaboration with educated and experienced farmers. Additionally, raising awareness among farmers about the water crisis and the importance of modern irrigation for enhancing production should be prioritized. Moreover, ensuring the accessibility of quality irrigation supplies at affordable prices, potentially through the facilitation of soft loans, stands imperative to incentivize adoption among interested stakeholders.

Soil compaction in progressive agricultural tractor treads

Soil compaction is one of the main problems in world agriculture. It is known that, even in soil conservation management, such as in no-till, the transit of agricultural machinery damages the soil structure, therefore, it is essential to better understand the compaction processes and ways to alleviate the problem. In soils that have traditional tillage management, just one machine pass can damage the physical structure. This research aimed to evaluate the levels of compaction as a function of different passages of an agricultural tractor, considering the hypothesis that, during agricultural operations, a machine transits several times through the same place in the crop. The experiment was carried out on plowed and harrowed agricultural soil in the state of São Paulo. Resistance to soil penetration at different depths was evaluated, and the averages were correlated as a function of the number of steps taken by the tractor. Results showed that approximately 60% of the total soil compaction occurs in the first passes of the agricultural tractor, and above five passes the increase in compaction is minimal. At depths of 20 to 30 cm, the largest RSPs were found. It is concluded that a good planning of machinery traffic is essential, because in the case of a motor-mechanized set moving out of its predestined route, the soil structure is permanently affected.