Spongy polydimethylsiloxane preparation and its applications for soft robotics

Abstract

Soft Robotics has come to the fore in the last decade as a new way of conceptualizing, designing, and fabricating robots. Soft materials empower robots with locomotion, manipulation, and adaptability capabilities beyond those possible with conventional rigid robots. The field of soft robotics utilizes compliant architects to minimize machine complexity and approach biological systems' mechanical and sensing capabilities. Recently, soft (i.e., compliant, and extensible) materials and structures have enabled machines capable of versatile locomotion as well as analogs for caterpillars, fish, jellyfish, and octopus tentacles. With reduced control complexity, these soft machines allow natural motion through continuous deformation and interact gently with fragile objects. The porous, elastic polymers are attracting the attention of researchers in this regard. Here, we demonstrate a facile method for fabricating the lightweight, low-density, elastic PDMS spongy material using sugar as a porogen for different soft robotics applications. The poroelastic material can hold the weight of the robot’s body as legs. This PDMS sponge also successfully demonstrates the application of oil-water separation material for swimming robots. The recyclability of absorption and ability to separate oil from water at different pH levels demonstrate that this material can be effectively used in various conditions. A solvent-light responsive biomimetic soft gripper engineering was investigated by changing the degree of crosslinking and successfully manipulating the swelling of PDMS porous material in different organic media. This soft gripper can lift and release objects in response to NIR light.