US Patent 10589434 Variable geometry and steady volume inflatable tube, robotic arm and robot

Disclosed is a variable geometry and constant-volume inflatable tube, including an inflatable envelope having a central axis. A stress-bearing unit is provided, including a pair of first and second inextensible link belonging to a same longitudinal half-plane of the envelope, the first unit being oriented along a first longitudinal direction inclined with respect to the central axis and the second unit being oriented along a second longitudinal direction which is also inclined with respect to the central axis but which crosses the first direction on the central axis. The inflatable tube can be bent around a first or second pivot axis, the longitudinal tensile stresses applied to the envelope then being concentrated on the central axis.