Apparatus, systems, and methods for modular soft robots

1. A soft robotic actuator comprising:

a plurality of molded flexible units, wherein each molded flexible unit comprises a mechanical connector configured to couple to another molded flexible unit, wherein each of the molded flexible units is solid, and the plurality of coupled molded flexible units are arranged to define a cavity;

an inlet coupled to the cavity, wherein the inlet is configured to couple the cavity to a pressurized fluidic source or a depressurized fluidic source to inflate or deflate a portion of the soft robotic actuator;

wherein the mechanical connector of each molded flexible unit comprises a male mechanical connector and a female mechanical connector, wherein the male mechanical connector of a first molded flexible unit is configured to couple to a female mechanical connector of a second molded flexible unit; and

wherein the cavity is separate from the male mechanical connector and the female mechanical connector.

2. The soft robotic actuator of claim 1 , wherein the male mechanical connector comprises a peg and the female mechanical connector comprises a recess.

3. The soft robotic actuator of claim 1 , wherein the mechanical connector comprises a single taper dovetail joint configured to provide a resistance to a tensile strain along a single lateral direction.

4. The soft robotic actuator of claim 1 , wherein the mechanical connector comprises a double taper dovetail joint configured to provide a resistance to a tensile strain along two directions.

5. The soft robotic actuator of claim 1 , wherein one of the molded flexible units comprises a heterogeneous material, and further wherein the mechanical connector on the one of the molded flexible units is formed using a stiffer material compared to that of its body.

6. The soft robotic actuator of claim 1 , wherein the plurality of molded flexible units is stacked on top of one another to form the soft robotic actuator.

7. The soft robotic actuator of claim 6 , wherein each of the plurality of molded flexible units comprises a plurality of holes, and the plurality of holes are aligned to form a plurality of cavities.

8. The soft robotic actuator of claim 1 , wherein some of the plurality of molded flexible units are arranged perpendicular to one another, thereby forming a cube actuator.

9. The soft robotic actuator of claim 1 , wherein the mechanical connector is positioned along an edge of the molded flexible unit, and at least two of the molded flexible units are coupled to one another using the mechanical connector positioned along the edge of the molded flexible units.

10. The soft robotic actuator of claim 1 , wherein one of the plurality of molded flexible units comprises a portion of a molded block that has been cut using a cutting tool.

11. The soft robotic actuator of claim 10 , wherein the cutting tool comprises one of a razor blade, a knife, and scissors.

12. The soft robotic actuator of claim 1 , wherein the plurality of molded flexible units comprises a first molded flexible unit and a second molded flexible unit, wherein the first molded flexible unit is less stiff as compared to the second molded flexible unit, and wherein upon pressurization or depressurization of the cavity, the first molded flexible unit is configured to expand more than the second molded flexible unit.

13. The soft robotic actuator of claim 12 , wherein the first molded flexible unit and the second molded flexible unit comprise a sidewall of the cavity, thereby providing a control of a direction and magnitude of expansion upon pressurization or depressurization.

14. The soft robotic actuator of claim 12 , wherein the first molded flexible unit is stacked on top of the second molded flexible unit, thereby providing a control of a location and magnitude of expansion along the cavity upon pressurization or depressurization.

15. The soft robotic actuator of claim 1 , wherein one of the molded flexible unit has a square-shape.

16. The soft robotic actuator of claim 1 , further comprising a glue between two molded flexible units for forming an air-tight coupling between the two molded flexible units.

17. The soft robotic actuator of claim 16 , wherein the glue comprises a polydimethylsiloxane prepolymer.

18. The soft robotic actuator of claim 16 , wherein the glue comprises a liquid Ecoflex prepolymer.

19. The soft robotic actuator of claim 1 , wherein a portion of one of the molded flexible units comprises a stiff material that is configured not to inflate or deflate upon pressurization or depressurization.

20. A modular soft robot comprising:

a plurality of soft robotic actuators in accordance with claim 1 ; and

a fluidic inlet coupled to the inlets of the plurality of soft robotic actuators, wherein the fluidic inlet is configured to receive pressurized or depressurized fluid and to provide the received fluid to the inlets of the plurality of soft robotic actuators to inflate or deflate a portion of the plurality of soft robotic actuators.

21. A method of actuating a soft robotic actuator, the method comprising:

providing a soft robotic actuator in accordance with claim 1 ;

providing pressurized or depressurized fluid to the inlet of the soft robotic actuator to cause an expansion of a wall of the soft robotic actuator, thereby causing an actuation of the soft robotic actuator.

22. The soft robotic actuator of claim 1 , wherein the male mechanical connector of a first molded flexible unit is configured to couple to a female mechanical connector of a second molded flexible unit to form air-tight connections.

23. The soft robotic actuator of claim 1 , wherein the soft robotic actuator further comprises a top layer and a bottom layer; and the plurality of molded flexible units are sandwiched between the top of bottom layers.