Design and experiment of flexible clamping device for pepper plug seedlings

At present, there are leakage and injury of pepper seedlings in the process of seedling transplantation. Based on the mechanical properties of pepper stem, a clamping mechanism with the function of crab pincers is designed using bionics principle. The clamping mechanism uses the CAM device to drive the gear and rack meshing. The control clamping gripper’s opening and closing stroke is 2–30 mm. The stroke of CAM gear is 1.94 mm, obviously save the clamping time. In order to achieve flexible clamping and reduce seedling injury, elastic silicone, rubber, and nylon materials were used as clamping materials. The finite element analysis was carried out to simulate the force in the clamping process, and the stress of the silicone gripper was found to be the minimum, and the stress range was 1.53 × 10−4–1.42 MPa. The results of clamping damage test and seedling picking migration test showed that the clamping damage rate of the silicone gripper was 3.28%. The clamping damage degree was the lowest, which is consistent with the theoretical analysis. The seedling leakage rate was 5.86%. The success rate of seedling picking was 94.14%, and the success rate of migration was 83.20%. It proved that flexible clamping device designed in this study had reliable working performance and good transplanting effect.