title: Stimuli-responsive cylindrical hydrogels mimic intestinal peristalsis to propel a solid object.
abstract: The emerging field of soft robotics relies on soft, stimuli-responsive materials to enable load transport, manipulation, and mobility in complex unconstrained environments. These materials often need to replicate biological functionality such as muscle contractions and flexibility. Here we demonstrate a soft actuator prototype based on thermosensitive PNIPAAM hydrogels that can transport and manipulate objects. A hollow cylindrical hydrogel was selectively heated and cooled with Peltier devices to yield a traveling wave of shrinking and swelling akin to intestinal peristalsis. A 4 mm diameter bead was placed inside the cylinder and propelled 19.5 mm, equal to distance traveled by the peristaltic wave. We derived conditions that enable peristaltic transport as a function of transporter-cargo design parameters. We conclude that hydrogel-based peristaltic manipulators covering 2 orders of magnitude in stiffness (1-10(2) kPa) could transport cargo spanning 4 orders of magnitude in size (μm-m).
authors.affiliation: Department of Biomedical Chemical and Environmental Engineering, University of Cincinnati, USA. licaseverin@gmail.com yeghialt@ucmail.uc.edu.
authors.forename: V
authors.initials: V
authors.lastname: Nistor
authors.affiliation: Department of Biomedical Chemical and Environmental Engineering, University of Cincinnati, USA. licaseverin@gmail.com yeghialt@ucmail.uc.edu.
authors.forename: J
authors.initials: J
authors.lastname: Cannell
authors.affiliation: Department of Biomedical Chemical and Environmental Engineering, University of Cincinnati, USA. licaseverin@gmail.com yeghialt@ucmail.uc.edu.
authors.forename: J
authors.initials: J
authors.lastname: Gregory
authors.affiliation: Department of Biomedical Chemical and Environmental Engineering, University of Cincinnati, USA. licaseverin@gmail.com yeghialt@ucmail.uc.edu.
authors.forename: L
authors.initials: L
authors.lastname: Yeghiazarian
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D032701:Biomimetics / Q000295:instrumentation / Q000379:methods*; D017276:Friction; D020100:Hydrogels; D007422:Intestines / Q000502:physiology; D009038:Motion; D010528:Peristalsis; D019736:Prostheses and Implants; D012371:Robotics; D013696:Temperature; D016474:Weight-Bearing
chemical_list: D000180:Acrylic Resins; D020100:Hydrogels; C052970:poly-N-isopropylacrylamide