Title :
Grasping without squeezing: Shear adhesion gripper with fibrillar thin film
Author :
Hawkes, Elliot W. ; Christensen, David L. ; Han, Amy Kyungwon ; Jiang, Hao ; Cutkosky, Mark R.
Author_Institution :
Dept. of Mech. Eng., Stanford Univ., Stanford, CA, USA
Abstract :
Nearly all robotic grippers have one trait in common: they grasp objects with normal forces, either directly, or indirectly through friction. This method of grasping is effective for objects small enough for a given gripper to partially encompass. However, to grasp larger objects, significant grip forces and a high coefficient of friction are required. We present a new grasping method for convex objects, using almost exclusively shear forces. We achieve shear grasping with a gripper that utilizes thin film gecko-inspired fibrillar adhesives that conform to the curvature of the object. We present a verified model for grasping a range of curvatures and results that demonstrate the thin film fibrillar adhesives´ increased contact area on textured surfaces when loaded in shear. Finally, the gripper is implemented on a robotic arm and grasps a variety of convex objects (at rest and ballistic).
Keywords :
grippers; thin films; convex objects; grasping method; robotic grippers; shear forces; shear grasping; thin film gecko-inspired fibrillar; Adhesives; Force; Friction; Grasping; Grippers; Load modeling; Springs;
Conference_Titel :
Robotics and Automation (ICRA), 2015 IEEE International Conference on
Conference_Location :
Seattle, WA
DOI :
10.1109/ICRA.2015.7139505