Bioinspired Machines

Soft Locomotive Robots

We have caused natural motion in synthetic robots by using organic elastomers (crosslinked polymers above their glass transition temperature) that deform continuously over large ranges of strain.
  • Large shape changes allow easy switching between gaits: walking or undulating.
  • The tough materials create robots capable of sustaining large impact forces without damage.
  • The robots can be scaled for a mission simply by increasing the size of the mold used to cast the rubber and choosing an appropriate elastic modulus for the material.
Relevant Publications:

Bicontinuous Liquid Metal Foams

We have developed a composite of two entangled foams: an elastomer and a low melting temperature metal, that exhibits dynamic shape morphing and shape memory actuation. Additionally, by melting and freezing the metal foam, the composites can both self-heal and be assembled into larger, continuous structures from smaller sub-components. The composite has been embedded into two soft robotic devices to demonstrate the capability for reversible stiffness in soft robots.
Relevant Publications:

Stretchable electroluminescent skin

We have developed a hyperelastic light emitting capacitor (HLEC) that can expand its surface area by >635% while actively emitting light and sensing this deformation. The center layer is a thin sheet of silicone with embedded ZnS phosphors that glow under a high electric field. Transparent, ionically conductive hydrogel electrodes sandwich the center dielectric layer.
Relevant Publications:

High-DOF, 3D-Printed Fluidic Actuators

Using our custom DMP-SL printer, we can quickly fabricate high resolution actuators from soft materials. Inspired by the complex three-dimensional arrangement of muscles in octopus tentacles, we have designed soft machines that incorporate multiple actuators into a monolithic, printed structure. These antagonistic pairs allow the printed tentacle to actuate over a wide range of motion. As shown in the video to the right, multiple antagonistic pairs can be combined to create complex, 3D motions.
  • High-DOF actuators can be quickly prototyped as a monolithic structure.
  • High speed actuation with periods of less than 70ms.
  • Working pressures greater than 345 kPa (50 psi).
Relevant Publications: