Development And Experiment Of Automatic Transplanting Machine For Elevated Strawberry Cultivation In Greenhouse

Strawberry is a nutrient-rich health fruit,and its economic benefits are much higher than that of vegetable crops.It is an important horticultural crop that improves the income of farmers,and it is developing rapidly in various places.China is the largest strawberry producer in the world,and its planting area is gradually increasing every year.Cultivation of greenhouse strawberries has also been rapidly promoted.As a new cultivation mode,elevated strawberry cultivation is more suitable for the development of tourism agriculture due to its highly comfortable operation and good ventilation.The transplanting of strawberry seedlings is the most important part of strawberry planting and management links,and the labor intensity is great.Therefore,it is necessary to develop a fully automated transplanting machine for strawberry seedlings grown under high temperature.The research work carried out in this paper and the conclusions obtained are as follows:(1)Through the investigation of environmental parameters of greenhouse elevated cultivation environment,the parameters such as the width of cement aisle,the distance between the inside and outside of the elevated platform,the elevated height,and the width of the planting trough were obtained in the elevated cultivation environment,which provided a size basis for the design of the transplanter.Analyze the speciality of the strawberry plug seedlings and the special requirements of the transplanting machine in the elevated cultivation environment,and provide the program basis for the design of the transplanter.Through the experiment and design of the key components of the transplanter,it provides the basis for the realization of transplanting operations of the transplanter.(2)Developed an automatic transplanting machine for punching and planting seedlings and two-line four-row planted high-grade strawberry seedlings,and designed a dual-mode control system based on PLC for remote control and automatic operation.The "light and simple" system scheme of the transplanter is proposed.The goal is to reduce the difficulty in the development of the transplanter system,enhance the human-machine interaction performance of the transplanter,and make the operation easier.Focusing on the characteristics of transplanting strawberry seedlings,the objectives of light and simple control were put forward,combined with the objectives,and the key electrical component data of the construction system were collected.The system components of the selection “light and simple” were compared with the operation method of the transplanting machine and the control system.The needs of the analysis,design control system electrical circuits,complete remote control-automatic dual-mode system development.(3)In view of the shortcomings of the existing electric-driven seedling-reversing reversing unit,a pneumatic unit was designed.The cylinder and air source parameters are obtained from the driving force(torque)and the operating speed of the seedling(variable pitch),and the design of the pneumatic system is completed.Finally,the stable operation of the pneumatic seedling-variable commutation unit is finally ensured by the supply-consumption air balance relationship in the pneumatic system.(4)Profiling drilling program was proposed.The experiment showed that the puncher had a sudden change in force when it penetrated the surface of the substrate.The contour punching was feedbacked with the threshold of soil resistance,and it was verified by experiments that under the elevated height range of 850~950mm,the profile drilling depth error was within 6mm,and the effect was significant.Taking the mean value of the bilateral elevated heights as the basis for replicating seedlings,on this basis,according to agronomic requirements,pressing down 10 mm is continued as the contouring seedling height.(5)Based on the profiling operation,the timing analysis of multiple movements of the transplanting machine is completed,and then the motion scheme is optimized,the parallel motion method is realized,the time-consuming time-consuming motion is reduced,and the operating efficiency of the transplanting machine is greatly improved.(6)Field trials showed that the transplanter efficiency was greater than 1000 plants per hour,and the success rate of transplanting exceeded 95%.The coefficient of variation of plant spacing,row spacing,and row straightness of transplanted plants was less than 7.5%,achieving high accuracy.