November 30, 2018
Small-Scale Soft Robotics
Soft functional active materials could enable physical intelligence for small-scale (from a few millimeters down to a few micrometers overall size) devices and robots by providing them unique capabilities, such as shape changing and programming, physical adaptation, safe interaction with their environment, and multi-functional and drastically diverse dynamics. In this talk, our recent activities on design, manufacturing, and control of new shape-programmable active soft matter and untethered soft robots at the milli/microscale are reported. First, elastomeric microfibers, inspired by gecko foot-hairs, are proposed as new reversible soft adhesives for robotics, as soft robotic gripper and climbing robot attachment materials, skin adhesives for soft wearable devices, etc. Second, red blood cell (RBC)-based soft microswimmers driven by attached E. coli bacteria are proposed as new active local drug delivery systems. These microswimmers carry cargo such as drugs and imaging agents inside the RBC, can be steered magnetically, and can be fully degraded via exposed NIR light. Third, untethered soft millirobots inspired by spermatozoids, caterpillars, and jellyfishes are proposed using elastomeric magnetic composite materials. Static and dynamic shapes of such magnetic active soft materials are programmed using a computational design methodology. These soft robots are demonstrated to be able to have seven or more locomotion modalities (undulatory swimming, jellyfish-like swimming, water meniscus climbing, jumping, ground walking, rolling, crawling inside constrained environments, etc.) in a single robot for the first time to be able to move on complex environments, such as inside the human body. Preliminary ultrasound-guided navigation of such soft robots is presented inside an ex vivo tissue towards their medical applications to deliver drugs and other cargo locally and heat the local tissues for hyperthermia and cauterization.