Soft robotic actuators and methods of manufacturing the same
Exemplary embodiments relate to various improvements in soft robotic actuators, and techniques for manufacturing the improvements. For example, techniques for manufacturing a rigidizing layer for reinforcing a soft robotic actuator is provided. In another embodiment, a soft robotic actuator having integrated sensors is described. A flexible electroadhesive pad for achieving a conformal grip is also described. Still further, exemplary embodiments provide hydraulically-actuated soft robotic grippers, which allows for a reduction in the size of the actuation system and improved underwater operation.
1. A rigidizing layer for a soft robotic actuator, the rigidizing layer formed by:
disposing a fabric sheet on a bottom plate of a hot press;
disposing a layer of thermoplastic material on the fabric sheet, the layer of thermoplastic material having a plurality of slots formed in it;
disposing a rigid slat in each of the slots in the layer of thermoplastic material;
disposing a compliant supportive layer on the layer of thermoplastic material and the slats;
disposing a top plate of the hot press on the compliant supportive layer;
operating the hot press to bond the fabric sheet, the layer of thermoplastic material, and the compliant supportive layer together to form a bonded sheet; and
cutting the rigidizing layer from the bonded sheet.
2. The rigidizing layer of claim 1 , wherein the fabric sheet comprises nylon.
3. The rigidizing layer of claim 1 , wherein the thermoplastic material comprises thermoplastic polyurethane (TPU).
4. The rigidizing layer of claim 1 , further comprising disposing a gasket on the compliant supportive layer, the gasket having a number and arrangement of slots formed in corresponding to a number and configuration of the slots formed in the layer of thermoplastic material.
5. The rigidizing layer of claim 1 , wherein the compliant supportive layer comprises a stretching foam.
6. The rigidizing layer of claim 1 , wherein the compliant supportive layer comprises spandex and neoprene foam.
7. A soft robotic actuator assembly comprising:
a soft robotic actuator comprising a plurality of accordion extensions extending outwards in a radial direction;
a camshaft connected to a first end of a follower;
a piston, connected to a second end of the follower, wherein the follower and the camshaft drive the piston, for supplying hydraulic fluid to a tube connected to the soft actuator to pressurize the soft actuator; and
an oblong lobe connected to the camshaft, wherein a pressure profile delivered by the piston is a function of a shape of the oblong lobe.
8. The assembly of claim 7 , further comprising a set of hydraulically-actuated soft actuators that are driven out of phase from one another by the action of a single piston chamber.
9. The assembly of claim 7 , wherein the piston is controlled by a linear actuator.