Multimodal Pressure-Actuated System Toward Adaptive Anchoring Within Complex Human Lumen.

Reliable anchoring is a critical enabling technology for stable manipulations within complex human lumen environments. Existing anchoring technologies may cause damage to the soft tissue or fail to adapt to the complex and variable shape of lumen. We propose a complex balloon anchoring mechanism driven by multimodal pressure, which could form a stable adhesion between the anchoring unit and the lumen. The combined driving pressures also enable shape adaptation to expand or contract as required. The manufacturing process for the balloon-type anchoring unit is detailed, which realizes high diameter/length ratio. The mechanics model is established, describing the deformation of the anchoring unit. Anchoring experiments were conducted in phantoms, mimicking both straight and tapered lumens, and ex vivo tissues. Anchoring performances were evaluated by comparing them with positive pressure-actuated single balloon and double balloon. The results demonstrate that the proposed anchoring technology achieves more reliable anchoring performance and adaptively adjusts the anchoring dimension.