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In order to improve the shelling efficiency of peanuts, the fracture mechanism of peanuts and the key components of the shelling test bench were studied. Firstly, the finite element method based on the cohesive element model was used to analyze the crack propagation of peanuts; the energy required for peanuts to crack was 0.06 J, and the maximum loading force was 30 N. Combined with the physical properties, mechanical properties, and shell-breaking energy of peanuts, the parameters of the two key components of the shell-breaking device and the adjustable grinding device were designed. The loading angle of the shell-breaking device was 30°, the mass of the rod was 1.5 kg, the mass of the hammer was 0.1 kg, the total length was 0.25 m, and the external contour of the grinding device was triangular. Through the field experiment, the single-factor test and the three-factor three-level regression test were designed, respectively, and the regression model of the removal rate and the damage rate was established. According to the response surface analysis of the regression model, when the feeding quantity is 12 pods/s, the speed of gear is 250 revolutions per minute, and the shelling clearance is 9.23 mm; the peanut removal rate reached 95.61%, and the kernel damage rate was 5.41%. However, the feeding amount was low and the damage rate was high, which could provide a reference for the future seed peanut sheller.

To address behavioral interferences such as head turning and lowering during rumination in group-housed dairy cows, an enhanced network algorithm combining the YOLOv5s and DeepSort algorithms was developed. Initially, improvements were made to the YOLOv5s algorithm by incorporating the C3_CA module into the backbone to enhance the feature interaction and representation at different levels. The Slim_Neck paradigm was employed to strengthen the feature extraction and fusion, and the CIoU loss function was replaced with the WIoU loss function to improve the model’s robustness and generalization, establishing it as a detector of the upper and lower jaws of dairy cows. Subsequently, the DeepSort tracking algorithm was utilized to track the upper and lower jaws and plot their movement trajectories. By calculating the difference between the centroid coordinates of the tracking boxes for the upper and lower jaws during rumination, the rumination curve was obtained. Finally, the number of rumination chews and the false detection rate were calculated. The system successfully monitored the frequency of the cows’ chewing actions during rumination. The experimental results indicate that the enhanced network model achieved a mean average precision (mAP@0.5) of 97.5% and 97.9% for the upper and lower jaws, respectively, with precision (P) of 95.4% and 97.4% and recall (R) of 97.6% and 98.4%, respectively. Two methods for determining chewing were proposed, which showed false detection rates of 8.34% and 3.08% after the experimental validation. The research findings validate the feasibility of the jaw movement tracking method, providing a reference for the real-time monitoring of the rumination behavior of dairy cows in group housing environments.

Electric tractors have many advantages, including high torque, excellent controllability, energy efficiency, a simple structure, and an electric interface for expansion. However, a significant limitation lies in their endurance. This study presents the design of an extended-range power supply system to ensure continuous endurance for an electric tractor. The objective is to provide a continuous power source for our self-developed electric tractor while preserving the benefits of electric propulsion. Extended-range power systems utilize a primary mover, typically an oil-fueled internal combustion engine, to drive the generator for electricity generation, and the generated AC-form electricity is subsequently converted into stable DC bus voltage by a power electronic converter. The hardware and control design of an extended-range power supply system are finalized and validated through experimental trials. The results demonstrate the system’s capability to sustain stable DC bus voltage amidst disruptions such as sudden load shifts and fluctuations in the prime mover’s speed. Even with a 50% sudden load change, the voltage drop is within 12% and can recover to ±3% within 4 s. The extended-range can be used alone without a battery to power the electric tractor, or it can used in parallel with other extended ranges or batteries for power sharing thanks to the droop control ability.

Improving the positioning accuracy and stability of a single BDS/INS sensor system in agricultural machinery is important for expanding the application scenarios of agricultural machinery. This paper proposes a navigation and positioning model based on an improved bee-colony-algorithm-optimized BP network (the IABC-BP model). The main aspect of this work involves introducing adaptive coefficients and speed adjustment coefficients that obey Gaussian distribution to ensure the balance between the rate of convergence, group flexibility, and searchability in the search process. The implicit adaptive layer formula of the BP network is proposed, and the BDS/INS navigation and positioning model for agricultural machinery is established using the IABC algorithm and the Kalman filter. Simulation tests and analyses of real-world application scenarios were conducted on the model, and the results showed that, compared with the original model, the performance of the model improved by 90.65%, 84.11%, and 25.96%, indicating that the proposed model has high accuracy and effectiveness. In the information fusion and compensation correction mode, the algorithm processes errors such as longitude and latitude within the target range and can achieve reliable navigation and positioning accuracy in a short period. At the same time, the model has good stability and generalization ability, and can be applied to other navigation scenarios in the future to expand its application scope.

Considering the problems of low soil fragmentation rates, high working resistance, and high energy consumption in the harvesting process of Cyperus esculentus in China, a method of Cyperus esculentus harvesting based on counter-rotation digging is proposed. The mechanism of interaction between the rotary tillage blade and Cyperus esculentus–soil is systematically investigated, and the vertical and horizontal disturbance performance of the positive and counter-rotating harvesting methods on soil and Cyperus esculentus is compared and analyzed. The results of the experiment showed that the intensity of soil and Cyperus esculentus disturbance by counter-rotation increased by 166.67% and 297.78%, respectively, and the effective disturbance time of soil and Cyperus esculentus increased by 133.33% compared to that of positive rotation. The working depth and rotation speed of the rotary tillage blade were the most significant for soil and Cyperus esculentus disturbance intensity. The working depth increased from 150 mm to 170 mm, and the soil disturbance intensity increased by 17.91% and 21.37% for positive and counter-rotating operation, respectively, and the rotation speed of the rotary tillage blade increased from 270 rpm to 330 rpm, and the soil disturbance intensity increased by 28.85% and 35.29%, respectively. Compared with the positive rotation operation, the Cyperus esculentus counter-rotation soil fragmentation rate increased by 4.09%, the Cyperus esculentus damage rate decreased by 10.69%, and the buried fruit rate decreased by 7.38%. This paper helps to understand the interaction mechanism between the rototiller and Cyperus esculentus–soil and lays a theoretical foundation for the subsequent design and optimization of the Cyperus esculentus digging device.

Currently, the mechanized harvesting method of Cyperus esculentus is mainly based on rotary excavation, but there are problems such as high working resistance, high damage rate, and high buried fruit rate in the working process. This paper focuses on the analysis of the movement trajectory of the positive-rotating and counter-rotating Cyperus esculentus excavation device, establishes a agglomerate model of soil-Cyperus esculentus tuber-Cyperus esculentus root system-mechanism, and conducts discrete element simulation tests on Cyperus esculentus agglomerates under different soil layers. According to Expert test optimization, the optimal structural parameters of the counter-rotating blade are determined: the radius of gyration is 151 mm, the inclination angle of the cutting edge is 42.5°, and the working width is 318 mm. The comparative test of the positive-rotating rotary tillage method under the optimal structural parameters shows that the working resistance is reduced by 11.25%, and the torque of the tool shaft is reduced by 16.11%, which proves that the designed anti-rotation excavation structure has the effect of reducing resistance. To further test the harvesting performance of the Cyperus esculentus excavation device, field harvesting tests were conducted, and the results showed that the buried fruit rate of the counter-rotating excavation device was reduced by 11.6%, and the damage rate was reduced by 6.1% year-on-year. This study shows that the design of the counter-rotating excavation device can further improve the harvesting performance of Cyperus esculentus based on reduced resistance harvesting and meet the requirements of Cyperus esculentus harvesting.

When peanuts are harvested, the high rate of pod crush and pods leakage are the main problems in the current peanut fruit picking process. Optimized peanut picking rollers help to improve peanut harvesting efficiency. This paper investigates the fruit picking system of a three-monopoly, six-row semi-feeding peanut combine harvester, in order to reduce the rate of crush and leakage of peanut pods during the picking process. Firstly, this article specifies the structure and basic parameters of peanut picking pairs of rollers. Secondly, this paper combines JKR (Johnson-Kendall-Roberts) model theory, crash model simulation analysis, a field test, and other methods. Motion and force analysis are presented in detail for the peanut picking mechanism and associated harvesting components. The optimum clamping chain speed, the angle of installation of the picking rollers to the clamping chain, and the picking rollers’ speed are determined. A three-factor, three-level regression orthogonal combination test was designed to obtain regression models for pod crushed and pods leakage rate. The regression model’s response surface analysis concluded that when the clamping chain speed is 0.84–1.2 m/s, the fruit picking roller angle is 10°–11.2° and the fruit picking roller speed is 442 r/min–500 r/min. It is the optimal working parameter for the three-monopoly six-row peanut combine harvester. At this point, the peanut harvesting requirements are met, and the overall performance is significantly improved. This paper lays the foundation for the development of the semi-feeding peanut picking system.

Soil blocking and plant entanglement are the main challenges in Cyperus esculentus harvesting and excavating. The structure of the rotary blade is one of the critical factors affecting plant crushing and soil throwing performance. Inspired by the composite motion of longitudinal soil cutting and lateral soil throwing of the oriental mole cricket, a bionic rotary blade was designed with the contour curve of the excavation edge and excavation surface of its forefoot claw toe. The bionic rotary blade’s mechanical and kinematic analysis revealed its cutting mechanism. A flexible plant soil, bionic, rotary blade discrete element model was developed to simulate the Cyperus esculentus digging process. The optimal excavation edge and excavation surface were selected by a single factor experiment, and the optimal operating parameters of the bionic rotary blade were obtained by quadratic regression orthogonal rotational combination design. The results showed that the bionic rotary blade, based on the excavation edge and excavation surface of mole cricket first claw toe, had the longest throwing distance and the largest number of broken bonds. The best combination of operating parameters of the bionic rotary blade was 11.16 mm for blade spacing, 0.66 m/s for forward speed, and 300 rpm for shaft speed. The field experiment was carried out according to the best parameters. The results showed that the bionic rotary blade’s average soil throwing distance and plant crushing rate were 632.30 mm and 81.55%, respectively; thereby, not only meeting the requirements of Cyperus esculentus harvesting, but proving superior to the operation performance of the Chinese standard rotary blade IT245 and rotary blade with optimized cutting edge (IT245P). The results of this study can provide bionic design ideas and methods for the design of soil-cutting-based tillage machinery’s soil-engaging components, such as the rotary blade and returning blade.

Severe plant entanglement and high power consumption are the main problems of the up-cut rotary blade during Cyperus esculentus harvesting. Optimization of the rotary blade edge can enhance the soil-cutting and plant-crushing performance. In this study, the double-eccentric circle method was used to design the edge curve of the IT245 rotary blade. The edge curve’s dynamic sliding-cutting angle of equidistant points was analyzed to verify that the optimized rotary blade (IT245P) met the requirements of Cyperus esculentus harvesting. In order to accurately simulate the fragmentation of Cyperus esculentus plants after interaction with the rotary blade, the Hertz–Mindlin with Bonding contact model was selected to establish the flexible model of Cyperus esculentus plants. The plant–soil–rotary blade discrete element model was constructed to conduct simulation tests with power consumption and the plant-crushing ratio as evaluation indexes. The field experiment was carried out with tillage depth stability and power consumption as the experimental indexes. The results of the simulation test and field experiment showed that the power consumption of the IT245P rotary blade was reduced by 13.10%, and the plant-crushing rate was increased by 11.75% compared with the IT245 rotary blade. The optimal operating parameters were 1.08 m/s for forward speed, 107.11 mm for tillage depth, and 258.05 r/min for shaft speed. Under such a combination, the tillage depth stability and the power consumption were 94.63% and 42.35 kW. This study showed that a rotary blade with a double-eccentric circular curve could better realize plant-crushing and consumption reduction and meet the operation requirements of Cyperus esculentus and other Chinese medicinal materials’ harvesting.

Traditional plant disease diagnosis methods are mostly based on expert diagnosis, which easily leads to the backwardness of crop disease control and field management. In this paper, to improve the speed and accuracy of disease classification, a plant disease detection and classification method based on the optimized lightweight YOLOv5 model is proposed. We propose an IASM mechanism to improve the accuracy and efficiency of the model, to achieve model weight reduction through Ghostnet and WBF structure, and to combine BiFPN and fast normalization fusion for weighted feature fusion to speed up the learning efficiency of each feature layer. To verify the effect of the optimized model, we conducted a performance comparison test and ablation test between the optimized model and other mainstream models. The results show that the operation time and accuracy of the optimized model are 11.8% and 3.98% higher than the original model, respectively, while F1 score reaches 92.65%, which highlight statistical metrics better than the current mainstream models. Moreover, the classification accuracy rate on the self-made dataset reaches 92.57%, indicating the effectiveness of the plant disease classification model proposed in this paper, and the transfer learning ability of the model can be used to expand the application scope in the future.

In this paper, an adaptive header height control system is designed. Through the influence of the natural frequency, ωn, and damping ratio, ζ, on the system’s dynamic index, the optimal hydraulic cylinder parameters are determined comprehensively. The ground profiling monitoring mechanism and the header height feedback mechanism based on the angle sensor are designed. An integrated electromagnetic proportional valve was installed to replace the original header-controlled, electronically-controlled reversing valve, and a PWM (pulse width modulation) control-simulated counterweight test was performed. The limitation of traditional PID facing the integral saturation state is analysed, and a new EVPIVS-PID algorithm is proposed and simulated. Through the analysis of multiple groups of sample data in the field test, the accuracy of the control system in the header height control and output PWM value is demonstrated. The effectiveness of the EVPIVS-PID control algorithm to change the corresponding PID parameters based on the monitoring operation speed is analysed and demonstrated. Experiments show that the adaptive control system of header height based on ground profiling has a stable control effect. The height error of cutting stubble is not more than 2 cm, which can meet the requirements of a 5–11 km/h harvesting speed in plain areas.

In order to solve the problems of easy-to-break kernels and substantial harvest losses during kernel harvesting in breeding trials plot of corn, an ear-picking device and a threshing device of corn plot kernel harvester has been optimized. To automatically change the gap of the ear-picking plate, a self-elastic structure with compression spring and connecting rod is used. The ear-picking plate is glued, and an elastic rubber gasket is placed underneath it, which effectively improves the adaptability of the ear-picking device and reduces corn kernel collision damage during ear-picking. To ensure the self-purification of the ear-picking device, a combination of auger sieve hole cleaning device and lateral pneumatic auxiliary cleaning system is used. A dual-axial flow threshing device is designed, which uses a “U”-shaped conveying system to transport maize ears in the threshing chamber. The spacing of the concave sieve may be adjusted, and the residual kernels in the threshing chamber can be cleaned up after harvesting one plot by combining three cleanings, which meets the requirements of no mixing between plots. The force analysis of corn ears in the threshing chamber determines the best design plan for the forward speed, the speed of the second threshing drum, and the threshing gap. The breakage rate and non-threshing rate regression models were created using the quadratic regression orthogonal combination test, and the parameters were optimized using MATLAB. The verification test results showed that when the forward speed was 0.61 m/s, the second threshing drum speed was 500 r/min, and the threshing gap was 40 mm, the breakage rate was 1.47%, and the non-threshing rate was 0.89%, which met the kernel harvesting requirements in corn plots.

In this study, the parameters of tiger nut were calibrated based on discrete element method, and significant influencing factors and optimal levels were selected by Plackett-Burman test, steepest climb test and center compound test, and verified by electromagnetic vibration hopper bench test. The results show that the relative error between the simulated resting angle and the actual resting angle is only 0.381%. The fitting degree of the model is 96.32% and 94.57% respectively, which can provide theoretical basis for the study of the parameters and discrete element simulation of tiger nut. [ABSTRACT FROM AUTHOR]

Aiming at the potato soil separation device of potato harvester, which generally has the problem of potato high damage in potato-soil separation, a three-stage potato soil low-loss separation device was developed, and orthogonal experiments were designed with the help of RecurDyn-EDEM coupled simulation method. A field bench was built for verification tests. The test proved that: when the lift transport chain speed was 1.40 m/s, travel speed was 0.60 m/s, amplitude was 32.0 mm, the impurity rate was 1.49% and the average force on potato was 1.801 N. The potato damage rate was 2.7%, indicating that the design of the three-stage potato soil low-loss separator device worked well. [ABSTRACT FROM AUTHOR]

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Aiming at the problems of low threshing efficiency and high damage rate of current threshing devices. In this study, the operational form of the threshing drum and the structure of the threshing element were innovated, and a new threshing drum with low damage and high efficiency was designed. Using EDEM software, flexible body modeling of corn kernels, cobs and whole ears was carried out. The dynamic analysis of the corn threshing process was completed and the simulation parameters were further optimized. The optimum operating parameters were analyzed by orthogonal rotational tests and response surface method with a speed of 800 r/min for the threshing drum, a clearance of 10 mm for the concave plate and 30 mm for the threshing drum. The radius of the round head of the threshing element was 5 mm. The height of the threshing element was 60 mm. The final threshing efficiency was 98.78% and the damage rate of threshing was 0.62%. The results show that the new threshing device can meet the requirements of low-loss threshing devices for corn combine harvesters and can provide a theoretical basis for the development of the theory and technical system of corn plot combine harvesters in the future. [ABSTRACT FROM AUTHOR]

For a peanut-picking device with a feeding rate greater than 5 kg/s, the problem of low picking rate and high damage rate will occur during the picking process. A discrete element model is developed to determine the range of values of the main influencing factors affecting the peanut picking device. A three-factor, three-level orthogonal combination test was carried out with feeding volume, drum speed, and peanut-picking gap as test factors to investigate the effects of the main influencing factors on the quality of peanut picking operation of the peanut-picking device. The results of the field trials showed that the best results were achieved at the optimum combination of drum speed of 508 r/min, peanut-picking gap of 22 mm, and feeding volumes of 6.3 kg/s. At this time, the peanut picking rate was 99.17%, and the peanut breakage rate was 0.91, meeting the standard technical requirements for mechanized peanut harvesting. The study results provide a theoretical basis for further enhancing the development of peanut combine harvesting equipment. [ABSTRACT FROM AUTHOR]

Pesticides play a key role in agricultural development, but pesticide residues do great harm to human health and environmental safety. Therefore, it is urgent to design a rapid and accurate pesticide monitoring method. Herein, a sensitive, label-free and nonenzymatic electrochemical sensor based on conducting polymer hydrogels, was constructed for the detection of carbaryl in aqueous solution. In this work, conducting polymer hydrogels were electrochemically prepared onto glassy carbon electrode by electrochemical copolymerization of polyaniline (PANI) and hyaluronic acid (HA). Interestingly, PANI/HA hydrogel with multiple porous microstructure and high active specific area demonstrated excellent hydrophilic and electrochemical properties, leading to the strong affinity to carbaryl pesticide. A non-enzymatic electrochemical sensor based on PANI/HA nanocomposite exhibited a linear response of 0.01–1 ng ml−1 for carbaryl, and the detection limit was 0.0034 ng ml−1. The PANI/HA modified electrode was used to determine carbaryl in the fruit samples, which showed efficient sensing ability. Therefore, the method can be popularized in the field of agricultural safety and environmental monitoring, and provides a promising avenue for the detection of pesticide residues in real samples. [ABSTRACT FROM AUTHOR]

Considering the problems of poor straw mulching performance, low soil crushing rate and poor straw mulching performance of the traditional rotary tiller on saline-alkali soils, a two-axis layered rotary stubble cutter for saline-alkali soils with front-axis positive rotation of the front axle and rear-axis counter-rotation of the rear axle was developed, focusing on the kinetic properties of the straw and soil under positive and counter-rotation. In addition, the most important structural parameters and the arrangement of the front-axis stubble cutting knife and the rear-axis return knife were analyzed and determined. Hertz-Mindlin with bonding was used to create a discrete element model of the agglomerate of implement, straw and soil. The forward speed, horizontal distance and vertical distance were used as test factors, and the straw return rate and soil fragmentation rate were used as test indexes to analyze the straw-soil transport law under different operating parameters from a microscopic point of view, and then Design-Expert was used to conduct the test 1.07 km/h, horizontal distance of 569.55 mm, vertical distance of 176.59 mm. To validate the performance of the two-axis, layered rotary tiller, a field trial was conducted and the results show that the straw return ratio was (91.59±0.41)%, soil fragmentation ratio was (91.90±0.29)% and tillage depth stability was (91.52±0.46)%, which met the requirements for peanut seedbed preparation on saline-alkali land. [ABSTRACT FROM AUTHOR]

Traditional passive ground wheel drive of peanut planters has displayed poor high-speed seeding performance and the slippage caused in case of sticky and wet soil. Given this, an integrated electric-driven precision seed metering device and controller were designed, which features the application of improved fuzzy PID algorithm. Based on a small peanut planter with one ridge width and duplicate rows, the servo motor drive is used to replace the traditional passive ground wheel. In addition, the satellite speed measurement is employed to complete the electric driving and controlling modification of the seed meter and precise seeding control. A working process mathematical model for the peanut metering device was established to conduct motor speed and field tests which aim at comparing performances between the conventional and the improved fuzzy PID controls. The motor speed trial shows that the average error of the actual speed of the improved fuzzy PID motor was ±1 rad/min, and the coefficient of variation was less than 1%. Against the conventional one, it can better suppress overshoot and improve the response speed. The stable output speed can still be obtained even in case of step changes. Field tests show that when working at medium and low speeds, the qualified rate of plant spacing was greater than 98%, and the rate of missed sowing is <2%; while working at high speed, the qualified rate was greater than 94%, and the rate of missed sowing was less than 4%. The average plant spacing qualification rate of the seed device increased by 6.72%; compared with other electric-driven peanut seed meters, the plant spacing qualification rate increased by 4% during high-speed sowing. In summary, this study has provided an effective technical reference for high-speed precision planting of peanuts. [ABSTRACT FROM AUTHOR]

In view of the fact that the current ground wheel velocimetry of the peanut precision fertilizer control system cannot solve the phenomenon of ground wheel slippage, and signal interference and delay loss cannot be excluded by BeiDou positioning velocimetry, a set of peanut precision fertilizer control system was designed based on the threshold speed algorithm. The system used STM32F103ZET6 microcontroller as the main controller, and touch screen for setting the operating parameters such as operating width, fertilizer type, and fertilizer application amount. The threshold speed algorithm combined with BeiDou and ground wheel velocimetry was adopted to obtain the forward speed of the tractor and adjust the speed of the DC drive motor of the fertilizer applicator in real time to achieve precise fertilizer application. First, through the threshold speed algorithm test, the optimal value of the length N of the ground wheel speed measurement queue was determined as 3, and the threshold of the speed variation coefficient was set to 4.6%. Then, the response performance of the threshold speed algorithm was verified by comparative test with different fertilization amounts (40 kg/hm², 50 kg/hm², 60 kg/hm², 70 kg/hm²) under two speed acquisition methods of ground wheel speed measurement and threshold speed algorithm (combination of Beidou single-point speed and ground wheel speed measurement) in different operation speeds (3 km/h, 4 km/h, 5 km/h). The response performance test results showed that the average value of the velocimetry delay distance of the BeiDou single-point positioning velocimetry method was 0.58 m, while the average value of that with the threshold velocity algorithm was 0.27 m, which decreased by 0.31 m and indicated more accurate with the threshold velocity algorithm. The field comparison test for fertilizer application performance turned out an over 96.08% accuracy rate of fertilizer discharge by applied with the threshold speed algorithm, which effectively avoided the inaccurate fertilizer application caused by wheel slippage and raised the accuracy of fertilizer discharge by at least 1.2% compared with that of using the ground wheel velocimetry alone. The results showed that the threshold speed algorithm can meet the requirements of precise fertilizer application. [ABSTRACT FROM AUTHOR]