Bioinspired Soft Robots with Integrated Biological Motion Mechanisms and Rigid–Flexible Coupling Systems

The inherent flexibility, safety, and biocompatibility of soft robots show significant potential for intelligent biomedical engineering applications. However, the unique operating environments of soft robots, including both in vivo and in vitro conditions, necessitate highly flexible movement capabilities. Optimizing the structural design to enable multi-degree-of-freedom motions is crucial to realize the expansion and deepening of soft robots in this field. Inspired by shape-morphing organisms in nature, researchers have recently developed a variety of bioinspired soft robots (BSR) with morphing capabilities that can realize motions such as bending, twisting, and stretching/contracting. The shape-morphing of organisms is determined by their unique motion mechanisms. This work comprehensively reviews the structure and morphology of typical biological prototypes with different shape-morphing behaviors, motion mechanisms, design strategies of the deformable BSR, and their vast applications in current biomedical engineering. Finally, this review also provides valuable insights into the current challenges and future opportunities for BSR.