Grasping for Climbing Robots Teresa Miller Randy Schuh

Challenges Choose single- and two-point climbing holds without concern for force closure. Assume: –2D –Constant friction –Hold represented by splines Force closed Non-force closed

Point Hold Selection Weighted function of: 1) Maximum coverage of 360 3) Average curvature of area around the point: 2) Curvature at the point

Point Hold Selection 2 Adds foot positions to other criteria Maximize: A∩B + A∩C foot holds hand hold stable region for the hand and right foot B stable region for the feet A stable region for the hand and left foot C A∩B A∩C

Two Point Hold Selection Weighted function of: 1) Curvature at two points 2) Friction cones 3) V-grip based quality metric –“Gripping Parts at Concave Vertices” by Gopalakrishnan & Goldberg α β α+β  close to 180 deg is best

Two Point Hold Selection Weighted function of: 4) Torque resistance secondary V-grip effect vs.

Future Work Additional robot constraints –Joint forces, torques –Collisions –Distance –Hand models forces on fingers grasp strength as function of finger separation Holds with disconnected regions Extend to 3D Fuse with Motion Planner