Design and Experimental Evaluation of a Posture-Adjustable Cable-Based Clamping–Cutting End-Effector for Safflower Filaments

Safflower filaments grow in random directions, whereas rigid-cutter picking end-effectors have large front ends and a fixed approach posture. To address these problems, a posture-adjustable cable-based clamping–cutting end-effector for safflower filaments was designed. Carried by a Delta parallel robot, it uses a two-axis deflection platform to align its axis with the flower growth direction and replaces rigid jaws and blades with twisted cable clamping and staggered twin-wire cutting. Twisted-string clamping and cutting-stroke models were established to determine the parameters of the guide orifice and the clamping and cutting mechanisms, and an end-effector–flower axis-angle test and a field picking test were conducted. The projected front-end area was 69.1% smaller than that of the previous-generation rigid-blade picking head. In single-attempt picking of 136 safflowers in the field, the complete clamping rate was 95.6%, the cutting success rate after complete clamping was 99.2%, and the clamping–cutting success rate was 94.9%. With the axes aligned (0–10°), the mass picking rate was 90.39%, within the range of values in the literature for rigid-blade end-effectors; at 30–40°, it decreased to 62.07%. The cable-based end-effector reliably clamps and cuts filaments with a small front end, and the end-effector–flower axis angle significantly affects the mass picking rate. These results provide a reference for the development of selective safflower picking equipment.