The soft NdFeB/Ecoflex composites for soft robot with a considerable magnetostimulated shrinkability

Abstract Shape deformation is a survival wisdom that many animals have evolved to protect themselves and prey foods easier. Soft magnetic composites provided an untethered strategy to allow the soft robots deform and move. However, it is great challenges for magnetic soft robots to squeeze in constrained environment, such as slits smaller than their sizes, as well as carry and release desired items. Here we demonstrate a magnetic hollow soft robot (MHSR) composed of soft NdFeB/Ecoflex composites, which has a considerable magnetostimulated shrinkability. The MHSR can squeeze through slits one fifth of its height and channels half of its height without structural damage. Notably, the MHSR can carry about twenty pellets to squeeze through a slit only half of its height, and then actively release them. Our design for deformable magnetic soft robots to squeeze through small slits or channels have laid a foundation for the development of soft robots to actively adapt to the constrained environment.