Fluidic actuator systems and methods for mobile robots

An exoskeleton system comprising:

• an inflatable actuator configured to be worn over a front portion of a foot of a user and configured to be disposed directly adjacent to and surrounding an ankle of the foot of the user, the inflatable actuator including:
• a fluid-impermeable member that defines a fluid chamber at least in part by a fluid-impermeable membrane material, the fluid-impermeable membrane material comprising an inextensible and flexible sheet of woven fabric folded in a tube configuration, the tube configuration having a first and second end and internal and external faces,
• a first and second planar interface that each define sidewalls, the internal face of the fluid-impermeable membrane material coupled circumferentially around the sidewalls of the first and second planar interfaces, with the first and second planar interfaces disposed respectively at the first and second ends of the tube configuration, at least one of the first and second planar interfaces defining a manifold configured to allow a fluid to flow into and out of the fluid chamber to inflate and deflate the fluid chamber, with inflation of the fluid chamber applying a force to the first and second planar interfaces, a shape of the fluid-impermeable membrane material defining a non-linear equilibrium state at a maximum inflation configuration of the fluid chamber that generates a mechanical stop at the maximum inflation configuration, and
• a first and second support element respectively coupled circumferentially around the sidewalls of the first and second planar interfaces and engaging a circumferential coupling between the fluid-impermeable membrane material and the sidewalls of the first and second planar interfaces to support the circumferential coupling between the fluid-impermeable membrane material and the sidewalls,
• a rigid foot structure coupled to a first actuator end of the inflatable actuator, configured to surround a top portion of the foot of the user, and
• a rigid shin structure coupled to a second actuator end of the inflatable actuator, configured to surround a portion of a shin of the user,
• wherein, the rigid foot structure and rigid shin structure are configured to, when worn by the user, receive and transmit an actuator load generated by the inflatable actuator to the foot and shin of the user;
• and
• wherein the inflation of the inflatable actuator generates a moment about the ankle of the user to cause flexion of the foot of the user.