Design of a PET plastic-loop robotic gripper with a soft-rigid palm for adaptive and enveloping grasping

Gripping of objects firmly without damage is a desired quality of a robotic gripper. Non-biomimetic grippers' design based on adjustable flexible loop capable of firm grip are yet to be widely explored in gripper design. This paper presents a 3D printed gripper design based on the grasping action achieved by holding the gasp object between a soft-rigid palm and a flexible plastic loop in tension which wrap round the object and the palm. Force analysis indicates the gripping force is proportional to the tension in the gripper's loop. The maximum payload depends on the friction coefficient at object-gripper interface and the magnitude of available gripping force. The gripper evaluation showed that the maximum loop tensile and gripping forces developed are 7.37N and 8.70N respectively. The gripper successfully demonstrated ability to grasped objects of various shapes, sizes, weights, and textures.