Soft Bioinspired Robot Module for Macro and Micro Manipulation

Soft robots are increasingly used in medical devices and industrial applications due to their flexibility and safer human-robot interaction. However, traditional soft robots often have fixed structures, limited functions, and constrained application scenarios. To address these limitations, modular design concepts have been introduced, allowing soft robot modules to be assembled into various configurations for adaptability across multiple tasks. Inspired by Drosophila larvae, this work builds upon our previously developed multi-segment soft crawling robot by focusing on the capabilities of a single soft module. The robot module is constructed from PET and actuated by four diagonally arranged shape memory alloy (SMA) coils. It features an ultralight (2.3 g) and compact structure(ϕ30 × 28 mm), enabling contraction (65%), bending (35°) and twisting (85°) movements. A fuzzy PID controller is introduced to precisely regulate deformation, achieving high-accuracy trajectory tracking with an average relative error below 2%. Experimental results validate both macro and microscale operations, including peg-in-hole insertion, object grasping and sorting, and embryo puncture. This work highlights the controllability and manipulation potential of bioinspired soft modules for future applications in confined spaces and fine manipulation scenarios.