Aiming at the problem that the existing methods of crop disease leaf detection were not accurate enough to locate the leaf disease region by using image features,  a new method of crop disease leaf detection based on multimodal feature alignment was proposed. During the training phase, image and text from a collection of crop leaves were first encoded using visual and text encoders. The diseased areas in a given image were located according to the visual encoding features, and the integration of visual and text encoding features was used to achieve finegrained classification of the type of disease in the diseased area. In the inference phase, the pretrained disease area localization module was used to locate the diseased areas in a given test image, and the extracted diseased areas were used as input for a pretrained classification model. Finally, by calculating the similarity between the predicted text values and the original labels in the text set, a rapid finegrained classification result for the diseased area was obtained. Tests on several opensource crop disease datasets show that the proposed method can achieve high precision rates of 0.957 4, 0.961 1, 0.958 0, and 0.950 2 on potato, tomato, apple, and strawberry datasets, respectively. It has better comprehensive perfor mance and good paratical application value.

In order to improve the seeding bud rate of hybrid garlic by planting garlic seeder, a method was put forward to control the direction of garlic seeds by using the lower center of gravity of garlic seeds and the elongated sprout tips of garlic seeds in series, namely，the sectional kind of groove was designed in the metering device stage, using garlic seed characteristics under focus on improving seed straight into the orientation of probability. In the commutation stage, the arc opening directional device was designed, the germination tips of garlic seeds were exposed as much as possible to improve the positive germination rate of garlic scaly buds with short bud tips. With orientation speed and seed tip length as test factors and positive bud rate as test index, bench test was conducted. The results showed that the effect of garlic bud tip length on the positive bud rate was obvious, and the positive bud rate decreased with the increase of orientation speed. Taking Jinxiang hybrid garlic as the experimental object, the field sowing performance of the directional system was tested. The experimental results showed that the positive budding rate of Jinxiang hybrid garlic reached about 85% when the walking speed was in the range of 0.14-0.19 m/s, which generally met the agronomic requirements of garlic sowing. Using the two physical characteristics of garlic seeds in series can improve the directional stability of garlic seeds from the operating principle. This study will provide a reference for the development of garlic seeding mechanization.

The process of rice straw and soil burial is an important factor affecting the return of straw to the field. In this paper, based on the previously established simulation model of the interaction between the straw return knife roller, soil, and rice straw, the motion state of soil particles was further studied. When the tillage depth was 20cm, the rotation speed of the cutter shaft was 240r/min, and the unit straw amount was 3.5kg/m2, simulation and indoor experiments were carried out with the straw burial rate and returning depth as the test indicators. The results showed a burial rate of 87.5% and 86.7% and a returning depth of 19.16 cm and 18.68cm, respectively, which validated the simulation and met the requirements of national standards. The simulation results showed that when the calibrated particle 152658 was in contact with the knife roller, it initially moved backward and downward. After reaching the lowest point, it was thrown backward and upward due to the rotation of the knife roller. The movement trajectory was approximately parabolic. The particle then fell back to the ground under the influence of gravity. It collided with other particles and generated fluctuations until it finally came to rest. The soil stress was studied by randomly calibrating the particles. The results showed that when the knife blade first contacts the soil particles, the forces in the X, Y, and Z directions of the particles increased linearly, and the maximum values were 15.61N, 37.2N, and 50.37N, respectively. After the soil particle mass was chopped by the knife blade, the force gradually decreased to 0. Similarly, by calibrating straw particle 45681 and analyzing its movement trajectory, the simulation showed that soil particles initially exhibited a dual effect of promoting and inhibiting the straw velocity. As the soil returned to the surface, the straw was mainly affected by soil friction under the soil layer until the straw velocity dropped to 0. The simulation analysis revealed the working principle of the straw return knife blade for straw burial and returning to the field from a microscopic point of view and provided theoretical support for the optimal design of components.

Leaf surface characteristics are an important variable for the deposition and retention of pesticide droplets on the surface of tea leaves. Incorporating the surface of the leaves into the study of droplet deposition characteristics is of great significance for a comprehensive understanding of the impact mechanism and movement rules of droplets on the surface of tea leaves. In the spray scene, the surface of the tea leaves is impacted by droplets in different directions. In order to explore the influence of impact angle, leaf curvature, and gravity on the droplet flow field and to visually display the flow field characteristics of the droplets during the movement, the tea tree leaves were reconstructed from the point cloud, and the droplet impact simulation was performed on the virtual leaf surface. Numerical simulation of drop impact was verified by theoretical models and laboratory experiments. Numerical simulation results showed that the smaller the impact angle was, the tangential velocity component of the droplet along the direction of movement on the leaf surface was greater than the normal velocity component, and the greater the difference between the two. When the droplet impacted obliquely, there was a slip phenomenon. The smaller the impact angle, the greater the droplet slip distance. Due to the slippage of the droplets, it was easy to cause the droplets to slip off the leaf, so it was recommended to use a 90° impact angle when spraying. When small and medium droplets with a particle size of 100-400 μm impacted the leaf surface, the initial spreading and contraction were mainly affected by the inertial force and surface tension. With the energy consumption, the speed decreased, and the curvature of the leaf had a greater influence on the droplet movement, which together with the droplet inertia and surface tension determined the stable form of the droplet. When the small and medium droplets were in contact with other droplets, coalescence would occur. Because the size of the small and medium droplets was small, the influence of gravity on the droplets was relatively small. For large droplets above 400 μm, the initial spreading and retraction were mainly driven by inertial force, surface tension and leaf curvature. As the droplets gradually condensed and became larger, the influence of gravity on the movement of droplets gradually became dominant. The verification found that the flow field characteristics of the droplets on the virtual leaves of tea trees were consistent with the theoretical analysis and experimental rules of the droplets impacting the surface of the tea leaves, and this simulation method was feasible. This research provided a new way to further improve the impact mechanism and motion law of droplets on the leaf.

For wheat harvester working path planning under complicated boundary problems, because the agricultural machinery operation paths largely determine the operation quality, efficiency, and cost, the cutter path planning model based on operation direction was set up, and an algorithm was presented in view of the convex and concave side boundary farmland with the least number of turns. The algorithm included the scanline method to calculate the number of turns with convex edges and the imaginaryregionfilling method to calculate the number of turns with concave edges. The rotation step method is used to calculate the optimal working direction corresponding to the minimum number of turns, and the optimal path trajectory of the harvester is obtained. The results of the simulation field boundary show that the optimization algorithm can effectively obtain the operation direction and path trajectory with the least number of turns. In the simulation case of the convex edge field, the optimization degree of the optimal operation direction can reach 11.32% compared with the path along the long side direction. In the field simulation case with concave edges, the optimization degree of the optimal operation direction is 5.66% compared with the path along the long side. The path planning model and algorithm can provide a certain decision basis for harvester harvesting in an actual complex boundary environment.

The mechanical state of the straw returning machine directly affects the returning quality and tool reliability. The optimization experiment of tillage parameters was carried out in the black soil with a water content of 30% and firmness of 700 kPa. It was concluded that the average value of cutter shaft torque was the smallest when the tillage depth was 20 cm, the rotation speed of the cutter shaft was 240 r/min, and the unit straw amount was 3.5 kg/m². Based on the tillage of parameters optimized and determination of the simulation of contact parameters and material parameters, the simulation interaction models of returning machete soil and returning machete soil straw were established by the discrete element method. The changes of torque of machete with and without straw were compared, analyzed, and verified by experiments. The simulation test showed that the maximum torque with and without straw was 25.8 N∙m and 21.7 N∙m, respectively, and the average torque was 19.5 N∙m and 17.4 N∙m. The average power consumption of knife roller with straw was greater than 12.1% of that without straw. The verification test showed that the maximum torque with and without straw was 32.3 N∙m and 26.7 N∙m, respectively, and the average torque was 23.7 N∙m and 21.3 N∙m. The average torque with straw was about 11.3% higher than that without straw. The comparative analysis showed that the changing trend of the test value and simulation value with or without straw was basically the same, but the test value was higher than the simulation value, and the data fluctuated and changed quickly.

Traditional electric tractors has some problems, such as low range, difficult to meet the operation demand of highpower section, etc., the incremental electric tractor is an additional power driving device based on the traditional electric tractor, which takes into account the economic and power requirements, and is one of the main development directions of the electric tractor in the future. On the basis of summarizing the main technologies such as power system research and energy management control strategy of incremental electric vehicle, this paper focuses on the research progress of incremental electric tractor in power system design, parameter matching and optimization algorithm with transmission system, torque distribution and energy management, and points out that precision, intelligence and how to find a better balance between power consumption and fuel consumption, improving the utilization rate of electric energy and reducing fuel consumption are the key and main development direction for the promotion of incremental electric tractors in the future. The modeling of the incremental electric tractor should fully consider the different operation needs of the tractor, such as transportation, soil ploughing, soil turning and land preparation. In the future, based on certain data analysis, the actual operation needs can be fully considered, and personalized and accurate modeling and parameter design can be implemented to improve accuracy. Based on the full analysis of the operating characteristics and energy demand of the extended range electric tractor, the research and development of batteries and related technologies suitable for the extended range electric tractor can be carried out to improve the endurance mileage.

 Chemical control is an important part of the comprehensive prevention and control of tea tree pests and diseases. It has the advantage of rapid and effective prevention and control when the pests and diseases are sudden or explosive. The surface of tea leaves is hydrophilic, and the constant application of pesticides can cause problems such as excessive pesticide residues in tea and damage to the ecological environment. Realizing reduced pesticide application of tea trees is an effective method to reduce pesticide residues in tea. The biological characteristics of tea trees, the predictive diagnosis and control methods of tea tree diseases and insect pests, tea tree protection machinery, and pesticide application technology were systematically reviewed. It was emphasized that improving the effective utilization of pesticides in lowvolume spraying of tea tree was the key to reducing tea tree application. In response to the current problems of complex ground conditions and low pesticide utilization in tea gardens, research recommendations on tea tree pests and diseases application technology and equipment had been put forward from six aspects, including lowvolume profiling sprayers, tea tree pests and diseases spray decisionmaking, and intelligent terminals. It was pointed out that low quantification, precision, and intelligence were the future development direction of tea tree protection spray machinery and application technology.

The identification of wheat heading at flowering stage can be used to guide the later water and fertilizer management, disease control, yield prediction and other aspects. In order to realize accurate and automatic ear counting, this paper proposes a new ear counting method based on color features. The color of wheat ear is very close to that of leaf and stem at heading flowering stage, and the common color features can not segment wheat ear effectively. In this paper, we extracted wheat ear effectively by color histogram equalization and red green normalized difference index. Aiming at the problem of wheat spike adhesion in the image, this paper uses the improved Harris corner detection algorithm to verify the wheat images taken at vertical angle and 45° angle respectively. Through the sample image counting experiment, the accuracy is 96.06% and 94.74% respectively. The results showed that there were obvious color differences in wheat ears, leaves and stems after equalization, and the color features could be used to extract the images of wheat ears at flowering stage in field environment. The detection of skeleton intersection point after wheat ear thinning can accurately count the conglutinated wheat ears with high counting accuracy, which can be used to reflect the situation of wheat heading in this period.