Self-locking friction based robotic gripper

摘要

A robotic gripper with two fingers for friction gripping. The fingers are self-locking in that an increased resistance to a pulling force results in an increased gripping force. The fingers are mounted onto a thumb that slides in a sleeve. A post extends into slots in the fingers so that movement of the post relative to the thumb causes the fingers to rotate around pivot points on the thumb. The friction force required to move the thumb relative to the sleeve is greater than the friction force required to move the post relative to the thumb. Therefore, movement of the post typically results in rotation of the fingers and a stationary thumb, but there are several ways in which the post can be locked relative to the thumb to provide movement of the thumb relative to the sleeve. The sleeve also includes features so that if an object is being gripped as the post is moving away from the sleeve, the fingers do not grip when the post is retracted. If no object is being gripped as the post is moving away from the sleeve, the fingers rotate to a gripping position as the post is retracted.