A Versatile End-Effector for Pick-and-Release of Fabric Parts

Abstract

A novel robotic end-effector is introduced for pick-and-release of several fabric parts used for producing underwear. One of the main operations in a factory for sewing cloth products is to pick up fabric parts, provide them to a sewing machine, and sew them together. In the case of underwear, thin cotton cloth is the target of manipulation. Since such cloth parts are placed in a stacked state, they tend to stick to each other, and a certain skill or technical acuity is required for picking up actions. Therefore, this work is typically mostly done manually at present. One purpose of this study is to automate such manipulation, so a mechanism is introduced to pick up only the top piece of cotton fabric from a stack. An essential part of the mechanism is an attached cylindrical brush with a removal cloth on its surface. The cylindrical brush is placed on the cotton fabric and is then rotated to roll up only the top piece of cotton fabric. This mechanism makes it possible to release the fabric by rotating the brush in the reverse direction. In addition, two sets of the cylindrical brushes are installed to face each other to enable pinching. This mechanism enables pick-and-release for various cloth parts, such as woven rubber pieces and piped cloth hems. Finally, a composite end-effector equipping these gripping functions is manufactured, and evaluation experiments are conducted using actual fabric parts.