title: Caterpillar-Inspired Design and Fabrication of A Self-Walking Actuator with Anisotropy, Gradient, and Instant Response.
abstract: A caterpillar-mimetic bilayer actuator is reported, based on a wrinkled polydimethylsiloxane elastomer decorated with a hydroresponsive polyelectrolyte brush. The actuator can fold ultrafast into complex three-dimensional structures upon a change in relative humidity of the surrounding air. The folding direction is determined by the geometry of the actuator, the orientation of the wrinkles, and the gradient in polymer height on the surface. And some unique structures such as helicoid and gradient can be obtained that are seldom reported in the case of bilayered devices. The adaptive bending movement is very fast, anisotropic, highly efficient, and reversible. When the environmental humidity is repeatedly cycled up and down, the small device walks on a surface with a roughness gradient, which is reminiscent of the muscle-like movements.
authors: State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Middle Road, 730000, Lanzhou, China.|University of Chinese Academy of Sciences, 100049, Beijing, China.
authors: Bin
authors: B
authors: Li
authors: State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Middle Road, 730000, Lanzhou, China.
authors: Tao
authors: T
authors: Du
authors: State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Middle Road, 730000, Lanzhou, China.
authors: Bo
authors: B
authors: Yu
authors: Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, NL-6703, HB, Wageningen, The Netherlands.
authors: Jasper
authors: J
authors: van der Gucht
authors: State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Middle Road, 730000, Lanzhou, China.
authors: Feng
authors: F
authors: Zhou
keywords: PDMS wrinkles; actuators; caterpillars; polyelectrolyte brushes; self-walking