Fig. 3.

Experimental setup of significance validation for hysteresis operation. The setup holds a proximal end of a bending body. A horizontal string pulled the tip of the bending body along in a direction parallel to the x-axis. Lateral positions of the tip were set to the preplanned values by using measurement microscope (STM-UM, Olympus, Tokyo, Japan). A load cell (LTS-2KA, Kyowa Electronic Instruments, Tokyo, Japan) connected to the signal conditioner (CDV-700A, Kyowa Electronic Instruments) measured a pulling tension on the string. The bending body bends along an arching direction by the lateral position of 44 mm and returns to the lateral position of 0 mm (a straight initial position) along an extending direction. These round-trip articulation experiments were performed twice for each bending body to create the hysteresis curve