A Bio-Functional Mimetic Robot for Versatile Tasks From Cross-Scale Manipulation to Limb-Tool Integration

Dexterous hands and robotic manipulators are essential physical interfaces for interacting with diverse environments. Traditional methods seek creature-like dexterity through structural biomimicry of biological systems, a strategy that results in increased mechanical complexity and control challenges due to the stacking of components. This study presents the BioflexBot, a functionally biomimetic robot that moves beyond structural replication. Utilizing dual air chambers and flexible coiled springs, it achieves three fundamental motions: extension, expansion, and contraction, controlled by only two inputs. These core movements, enabled by an optimized structural design, unlock three distinct functional domains, i.e., human-like grasping through bio-functional mimicry, adaptive growth surpassing human biological limits (reaching a 7:1 extension-to-contraction ratio), and enhanced performance via tool-hand integration. Experimental validation demonstrates that BioflexBot can manipulate objects up to 12.9 times larger than comparable systems, leveraging its lightweight, expandable design. This robot also supports diverse applications, including safe end-effectors for humanoid robots and in situ inspection of aeroengine blades within confined spaces. This work establishes that bio-functional mimetic design empowers simple mechanical structures to deliver robust multifunctionality, offering a novel solution that overcomes the longstanding trade-off between versatility and complexity in robotic manipulation.