Optimal Design And Experiment Research Of Hybrid-driven Five-bar Flower Potted-seedling Transplanting Machine

The transplanting of flower potted-seedlings is labor-intensive work,and the United States and Australia have developed fully automatic flower potted-seedling transplanting production lines.Their flower potted-seedling transplanting mechanisms are a combination of a machine,electricity,and gas and have independent mechanical parts and control parts,which are driven by a four-needle cylinder.Their mechanisms require the coordination and cooperation of multiple mechanisms,and the cost of the equipment is high,which is unbearable for small and medium-sized flower production enterprises.Due to the large transmission range of potted seedlings,transplanting work in arid areas is often accomplished by two sets of mechanisms – a seedling pick-up mechanism and a seedling planting mechanism,which involves the pick up the seedling from the potted-seedling box and planting the seedling into the field.More complicated demands are required for the designers to achieve such motion using a single mechanism.A hybrid-driven mechanism not only has the strong rigidity and high production efficiency of the traditional mechanism but also has as complex an output as the full servo mechanism.It possesses a flexible output and combines the advantages of the traditional mechanism and the full servo mechanism well.However,the experiment and the applied research of such a mechanism are mostly limited to the field of linear output mechanisms,such as the press.A hybrid-driven five-bar mechanism is proposed to create the complex trajectory and attitude requirements of flower potted-seedling transplanting.A hybrid-driven mechanism were optimized based on the genetic algorithm toolbox of MATLAB,the parameters of key components were modeled based on ADAMS.At the same time,the control system of automatic flower potted-seedling transplanting is designed.On the one hand,it selects the category of the origin return mode of the servomotor.On the other hand,it designs the synchronous control system and the matching control system.The 2D and 3D models were produced and processes it into real objects.During the process of the planting,the control system OPR and the shaking problem of the transplanting arm were found and were improved.Finally,the test of hybrid-driven mechanism was carried out and the success rate of the picking-up and seedling was tested.The main contents are as follows:1)In order to adapt to the requirement of fully automatic flower potted-seedling transplanting production,a five-bar linkage mechanism was put forward.According to the requirements of the work,designed the trajectory of "single-loop buckle",2)Based on the MATLAB,a inverse kinematics and optimization software for the flower potted-seedling transplanting mechanism was designed.The minimum fluctuation of the variable speed motor was taken as the optimization target,and The position of the rack was(0,-150),(-267.20,61.87).The rod length of the five-bar mechanism was 152.8,324.55,336.56,100.4,302.6,341.00 mm respectively,and the length of the frame was 500×500mm,3)The design of prototype and virtual simulation of the mechanism were carried out.The structure design were carried out including the five-bar mechanism,the transplanting cam and the transplanting arm.The 2D,3D drawing of the mechanism is drawn and the mechanism were assembled,4)Design the control system of the hybrid-driven five-bar mechanism.For the precise position control required by the mechanism,the position mode of the servo motor was adopted.the number,pulse frequency and pulse direction of the high speed pulse were sent by STC15 single chip microcomputer.The absolute position servo motor was used to return to the specified home position when the machine was turned on.The closed-loop system was used to control and the feedback was realized in real time when the error occurred.At the same time the synchronize control and real-time matching control system is to achieve the exact location of the flower potted-seedling transplanting requirements,5)The transplanting experiments of potted-seedling transplanting were carried out,and the mechanism and control problems found during the experiment were improved.The experiment proved that the hybrid-driven potted-seedling transplanting could achieve the flower potted-seedling transplanting trajectory,but also ensure the success rate in process of picking-up and seedling.