Fabrication of folding microstructures actuated by polypyrrole/gold bilayer

We have developed a method to fabricate substrates that can fold themselves. The microstructures are actuated by an electroactive polymer, polypyrrole (PPy). A series of bilayers is defined on one surface of the substrate, and hinges are formed by etching the substrate from the back side to undercut the bilayers. A shape-morphing object is demonstrated that comprises multiple hinges. This object was able to bend both forward and backward. We are applying this technology to fabricate medical devices that operate in bio-fluids.