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To address several challenges, including low efficiency, significant damage, and high costs, associated with the manual harvesting of Agaricus bisporus, in this study, a machine vision-based intelligent harvesting device was designed according to its agronomic characteristics and morphological features. This device mainly comprised a frame, camera, truss-type robotic arm, flexible manipulator, and control system. The FES-YOLOv5s deep learning target detection model was used to accurately identify and locate Agaricus bisporus. The harvesting control system, using a Jetson Orin Nano as the main controller, adopted an S-curve acceleration and deceleration motor control algorithm. This algorithm controlled the robotic arm and the flexible manipulator to harvest Agaricus bisporus based on the identification and positioning results. To confirm the impact of vibration on the harvesting process, a stepper motor drive test was conducted using both trapezoidal and S-curve acceleration and deceleration motor control algorithms. The test results showed that the S-curve acceleration and deceleration motor control algorithm exhibited excellent performance in vibration reduction and repeat positioning accuracy. The recognition efficiency and harvesting effectiveness of the intelligent harvesting device were tested using recognition accuracy, harvesting success rate, and damage rate as evaluation metrics. The results showed that the Agaricus bisporus recognition algorithm achieved an average recognition accuracy of 96.72%, with an average missed detection rate of 2.13% and a false detection rate of 1.72%. The harvesting success rate of the intelligent harvesting device was 94.95%, with an average damage rate of 2.67% and an average harvesting yield rate of 87.38%. These results meet the requirements for the intelligent harvesting of Agaricus bisporus and provide insight into the development of intelligent harvesting robots in the industrial production of Agaricus bisporus.

Refractance window (RW) drying is a new thin-layer drying technology that can control well the heating temperature to effectively reduce the loss of heat-sensitive substances. Here, an experiment on tomato pulp drying was carried out to study the drying characteristics of RW drying based on a D-optimal mixture design. The fitting of the classical model of thin-layer drying was studied, and SAS and 1stOpt calculation software were used to analyze the test data. The result showed that the RW drying equipment could dry 8 mm of tomato pulp in 120 min, and the maximum drying speed could reach 0.40 g/(g·min). Based on an effective diffusion coefficient under different conditions, the activation energy was 27.35 kJ/mol at an air speed of 3 m/s. When comparing the fitting of the moisture ratio curve in four classic thin-layer drying models, it was found that the R-square value of the modified Page model was 0.9960, which had better fitting properties. Then, the polynomial fitting model of thin-layer drying reflects the regression relationship between the coefficient of the classic model and drying conditions including temperature, wind speed, and time. After comparison with the classic model and validation experiment, the results showed that there is no significant difference between the polynomial fitting model and the validations under a confidence level of 0.95, which could well predict the change in the water content ratio over time under different conditions.

This study determined the physical and mechanical characteristics of fresh black fungus during the harvesting season to provide basic data for the development of mechanical equipment for black fungus harvesting and processing. We have conducted a comprehensive test of black fungus cultivars “Heishan”. The mono-factor separation force experiments of black fungus and black fungus virgulate medium were conducted. It was noted that the tension angle was an important factor affecting the separation force, which was mainly distributed between 1.06 and 3.65 N. Besides, the average value of Poisson’s ratio of black fungus was measured to be 0.445 in the tensile test of black fungus leaves using image recognition and analysis techniques, with a test error within 2.5%; and the average value of tensile elastic modulus and shear elastic modulus of black fungus leaves was 0.947 MPa and 0.327 MPa, respectively; we also found that the average tensile strength at the root of black fungus was not significantly different from that at the leaf, which was around 0.436 MPa. In addition, it was obtained that the height and thickness dimensions of black fungus in the picking season conformed to a normal distribution, and concentrated around 34.39mm and 0.92mm respectively.

The Auricularia auricula harvester has low harvesting productivity, low qualification rate, and high breakage rate, and the lack of research on key operating parameters has become a bottleneck restricting the large-scale development industry. In view of the difficulty of industrialization and promotion of Auricularia auricula harvesting equipment, this paper combines the research on the physical properties of Auricularia auricula, adopts a quadratic orthogonal rotation combination design test and response surface analysis method to carry out the optimization and test of the key parameters of the harvesting equipment of Auricularia auricula, including the speed of the tray fungus stick (A), the frequency of the harvesting knife (B), and the distance of the harvesting knife (C). Design-Expert software was used to analyse the data and investigate the influence of each parameter and its interaction on the harvesting productivity, qualified rate, and breakage rate. The test results show that the factors affecting the harvesting productivity are in order: (A) > (B) > (C); the factors affecting the harvest qualification rate are in order: (C) > (B) > (A); and the factors affecting the harvesting damage rate are in order: (C) > (B) > (A). The multi-objective optimization results show that the optimal parameter combination of the key parameters of the Auricularia auricula harvesting equipment operation is that the tray speed is 308.17 r/min, the harvesting knife frequency is 10.78 Hz, the spacing between the harvesting knives is 84.67 mm, the productivity is 363 bags/h, the pass rate is 94.26%, and the breakage rate is 2.40%. The field production application under this optimized parameter combination shows that the productivity of the Auricularia auricula mechanized harvester is 346 bars/h, the qualified rate is 91.43%, and the breakage rate is 3.19%. This study can provide a reference for improving the quality of Auricularia auricula harvesting equipment.

In order to further decrease the energy consumption of desiccant wheel dehumidification, the drying medium circulation characteristics of a system combining heat pump drying with desiccant wheel dehumidification were investigated. Moreover, the critical dehumidification conversion mechanism was studied. The analysis of the heat pump hot air circulation system demonstrated that the heat pump system has the best dehumidification efficiency. Through the analysis of the system combining heat pump drying with desiccant wheel dehumidification, the critical conversion point was determined. The critical dehumidification mechanism was further verified using an online temperature and humidity measurement system. To investigate the effect of the critical point on energy consumption and drying quality and develop a drying model, response surface experiments were performed based on the effects of regeneration temperature, drying temperature, and conversion point relative humidity on rehydration, color difference, and specific moisture extraction rate (SMER). The optimal conversion point humidity was determined to be about 46% RH, which was slightly different from the test optimization value of 45.6% RH. In addition, comprehensive optimization and experimental verification of the influencing factors were conducted. The results demonstrated that the R2 values of the three models were greater than 0.98, and the experimental factors had a significant effect on drying quality and energy consumption. When the regeneration temperature was 96°C, the drying temperature was 53°C, the relative humidity of the conversion point was 46%, the color difference was 46.3, the rehydration ratio was 5.75, and the SMER was 1.62 kg/kW·h.

The fixture design of the bacteria bottle plays a vital role in designing a bottled fungus picking robot to save labor cost in the picking process of bottled fungus. This paper proposed a kind of clamping element design method based on regression models. Several sets of clamping elements were designed according to the appearance data of bacteria bottle. A single-factor test was conducted by using these clamping elements, and three levels of every factor were selected to obtain the desired values of clamping elements. Then, a Box–Behnken test was performed by selected levels. The established regression models described a numeric relationship between the variation of vital measurement points and all variation sources under a precise clamping element layout. To solve the problems in obtaining the direct parameters, a response surface method was presented based on the regression models. Finally, a test was used to demonstrate the effect of the optimized clamping elements when clamping a bacteria bottle. Through the related analysis and optimization, it was demonstrated that the holding effect of the clamping elements was the best under these conditions: the inner arc area was 4948 mm2; the downward displacement was 1.48 mm; and the rubber thickness was 3.69 mm. It showed that the proposed method was feasible, and the assembly quality after optimizing had been greatly improved. It can provide a reference for designing the bottle fixture of a picking machine.

Along with the rapid development of edible fungus industry in China, the traditional mode of production giving priority to wood chips will be severely limited, and using agricultural waste distributed widely, having large yield, and containing high content of organic matter to produce edible fungi has good economic and ecological benefit. In this paper, based on the analysis of characteristics of agricultural waste in China, the present situation of application of agricultural waste in the production of edible fungi at home and abroad was introduced, and the main problems existing in production of edible fungi by using agricultural waste in China at the present stage were pointed out. Finally, the development direction of using agricultural waste to cultivate edible fungi was discussed, and some suggestions were put forward, such as improving the theoretical system for using agricultural waste to produce edible fungi, and establishing the standardized technical system for using agricultural waste to produce edible fungi. [ABSTRACT FROM AUTHOR]