Existing fully-automatic transplanters suffer from issues such as low accuracy in conveying and positioning seedling trays, inefficient picking and throwing due to complex movement paths, and seedling damage during the picking process. To address these challenges, this study presents innovative devices for seedling conveying in the X-direction and seedling picking in the Y-direction, considering both row and longitudinal intervals, which simplifies the mechanical structure. Based on these devices, methods were developed to achieve precise seedling positioning in both X and Y directions using multi-sensor combinations and motor control. A Finite State Machine (FSM) model was employed to propose a cooperative method for conveying and picking seedlings, simplifying the execution order and enabling continuous action without dragging or injuring the remaining seedlings. Experimental validation using 72-hole trays demonstrated that positioning deviation increased with motor pulse frequency, with a maximum deviation of 1.35 mm at 800 Hz, which remains within operational requirements. The qualification rate of seedling positioning was 100 % under various transmission speeds. The soil damage ratio (sDR) was measured to evaluate picking success, revealing an average successful seedling extraction rate of 95 %. These research findings offer technical support for efficient coordination between seedling conveying and picking in automatic transplanters.

To address problems encountered in current potato harvesting machines, such as potato damage, poor adaptability, and low operational efficiency, a new towed potato picking and bagging machine (4UJ-180A) equipped with a soil-digging axis, flexible conveying device, and hydraulic control system was developed. The digging mechanism of the harvester can reduce soil blockage and minimize damage to potato skins. The rubber biomimetic finger can maintain stable transportation of potatoes and minimize collisions. The hydraulic control system, the buffering components, and the bagging device work together to flexibly and continuously collect potatoes, reducing skin damage during the harvesting process. Based on the structure of the whole machine, the harvesting process, and the working principle, the soil picking, lifting buffer, and potato collection process were analyzed. Theoretical calculations were used to determine the structure and operational parameters of the potato picking, lifting buffering, and bagging segments. An experiment utilizing the orthogonal method was conducted. The experiment consisted of three factors and three levels, with the test indicators being the potato skin damage rate, potato injury rate, loss rate, and impurity rate. The factors considered in the experiment were the forward speed, conveyor speed, and soil-digging shaft speed. Field experiments demonstrate that at a forward speed of 1 m/s, soil digging shaft speed of 35 rpm, and conveyor speed of 28 rpm, the rate of potato skin damage is 2.8%, the potato injury rate is 1.3%, the loss rate is 0.4%, and the impurity rate is 0.7%. These experiments verify that all indicators adhere to national industry standards, providing a valuable reference for equipment research, development, optimization, and improvement.