A fluid pressure actuator is provided with an actuator main portion whose shape is changed by the expansion or contraction of a cylindrical tube expanded and contracted by the pressure of fluid, and a detection unit for detecting the length L of the actuator main portion along the longitudinal direction of the tube.

Proposed is a CFRP surface coating method and a hydraulic cylinder including a component coated by the method. The CFRP surface coating method can prevent damage to a CFRP surface due to thermal spray coating and increase the bonding strength between a CFRP surface and a metal coating layer formed by the thermal spray coating. To this end, the method includes: forming a mesh layer on a CFRP surface; fixing the mesh layer on the CFRP surface by impregnating a heat-resistant resin therein; and forming a metal coating layer by thermal spray coating on the fixed mesh layer in which the heat-resistant resin is impregnated.

A pneumatic textile system capable of transforming from a two-dimensional structure to a three-dimensional structure under pneumatic pressure is provided. The pneumatic textile system includes a seamless knit fabric having a grid configuration defining a plurality of grid areas—a first of the plurality of grid areas having a tensile strength that is different from a second of the plurality of grid areas. A pneumatic bladder member is disposed along at least a portion of a boundary between adjacent ones of the plurality of grid areas and is inflatable to exert a force on the seamless knit fabric, wherein upon inflation of the pneumatic bladder member the force is exerted on the seamless knit fabric such that the first of the plurality of grid area assumes a shape different than the second of the plurality of grid areas resulting in a three-dimensional structure transformation.

A composite cylinder for an actuator. The cylinder includes: a radially inner fibre-reinforced polymer layer defining a hollow bore; a radially outer fibre-reinforced polymer layer; a primary conductive coil, and a first and second secondary conductive coil wound between the radially inner fibre-reinforced polymer layer and the radially outer fibre-reinforced polymer layer. The first secondary conductive coil extends axially along at least a first region of the cylinder and the second secondary conductive coil extends axially along at least a second region of the cylinder, and wherein the primary conductive coil extends axially along at least a central region of the cylinder between the first region and the second region.

Elastomeric actuators and methods of making the same are provided herein. In some examples, an actuator includes a body comprising a plurality of pairs of frustums, wherein the body is configured to receive a fluid to extend the actuator and to remove the fluid to contract the actuator. In some examples, each pair of frustums includes two thin frustum shells sharing a common base circle diameter.

An artificial muscle includes a housing including an electrode region and an expandable liquid region and a dielectric liquid housed within the housing. The artificial muscle further includes an electrode pair positioned in the electrode region of the housing, the electrode pair comprising a first electrode and a second electrode, wherein the electrode pair is configured to actuate between a non-actuated state and an actuated state such that actuation from the non-actuated state to the actuated state directs the dielectric liquid into the expandable liquid region, expanding the expandable liquid region. The artificial muscle also includes a composite electrical insulating layered structure in contact with at least one of the first electrode or the second electrode, wherein the composite electrical insulating layered structure that includes an electrical insulator layer surrounded by adhesive surfaces. The adhesive surfaces are located between one or more flexible electrical insulators.

An object of the present disclosure is to provide an actuator having even better durability than the conventional actuator. Specifically, an actuator has an actuator main body constituted of a cylindrical tube capable of expanding/contracting by hydraulic pressure and a sleeve for covering an outer peripheral surface of the tube, the sleeve having a cylindrical structure formed by cords woven to be disposed in predetermined directions, wherein: the inner diameter r.sub.0 (mm) of the tube, the thickness t (mm) of the tube, the storage elastic modulus E′ (MPa) of the tube at 25° C., and the mesh aperture ratio A of the cords constituting the sleeve in a pressurized state satisfy the following formula (1):
50≤E′×(t/r.sub.0)/A≤600  (1).

A pneumatic textile system capable of transforming from a two-dimensional structure to a three-dimensional structure under pneumatic pressure is provided. The pneumatic textile system includes a seamless knit fabric having a grid configuration defining a plurality of grid areas—a first of the plurality of grid areas having a tensile strength that is different from a second of the plurality of grid areas. A pneumatic bladder member is disposed along at least a portion of a boundary between adjacent ones of the plurality of grid areas and is inflatable to exert a force on the seamless knit fabric, wherein upon inflation of the pneumatic bladder member the force is exerted on the seamless knit fabric such that the first of the plurality of grid area assumes a shape different than the second of the plurality of grid areas resulting in a three-dimensional structure transformation.

Hydraulic cylinders and methods of fabricating hydraulic cylinders, including long-stroke rolling diaphragm cylinders with any stroke length. In some embodiments, the cylinders are manufactured to have a stroke length to bore diameter (“stroke-to-bore”) ratio optionally greater than 1:1. Various embodiments are suitable for use in a passive hydraulic body-powered wearable robot, for example.

An improved pistonless cylinder, including both single acting and double acting configurations, based on an Aramid fiber reinforced elastomer tubular which is highly stiff in radial direction against radial expansion and elastic in axial extension, so as to form a completely sealed, extendable and retractable pressure chamber and to be able to perform as well as, or better than, most of the conventional hydraulic cylinders in terms of load bearing capacities, maximum stroke distances and service durability. This improved cylinder employs no piston, piston rod, sealing seals or oil based hydraulic fluid, and utilizes non-metal materials to construct the majority of the parts for its extendable and retractable pressure chamber; therefore, this new cylinder can achieve significant weight and fabrication cost reduction. In addition, this new pistonless cylinder uses ordinary liquids, e.g., fresh water or seawater, as its hydraulic fluid, and can work directly as a hydraulic or pneumatic cylinder interchangeably without a need for much, if any, modification.