A Mechanical Screwing Tool for Parallel Grippers—Design, Optimization, and Manipulation Policies

This paper develops a mechanical tool as well its manipulation policies for 2-finger parallel robotic grippers. It primarily focuses on mechanism that converts the gripping motion of grippers into continuous rotation to realize tasks like fastening screws. The essential structure comprises Scissor-Like Element (SLE) and double-ratchet mechanism. They together convert repeated linear rotating motion. At joints SLE mechanism, elastic elements are attached provide resisting force holding producing torque output when gripper releases tool. is entirely mechanical, allowing robots use without any peripherals power supply. presents details design, optimizes dimensions effective stroke lengths, studies contacts forces achieve stable grasping screwing. Besides include visual recognition, picking-up manipulation, exchanging tooltips. developed produces clockwise at front end counter-clockwise back end. Various tooltips can be installed both two ends. Robots may employ exchange directions following needs specific or loosening tasks. also reorient using pick-and-place handover, move work poses policies. designed tool, with policies, analyzed verified in several real-world applications. small, cordless, convenient, has good robustness adaptability.