Fig. 7

Deformations of a rubber band gripper at various vacuum pressures (0, − 5, − 10, and − 30 kPa). The gripper significantly contracts even at the low vacuum pressure (− 5 kPa). The gripper significantly shrinks at a low vacuum pressure (− 5 kPa). The inner diameter of the gripper was nearly a minimum at − 30 kPa