Suction is a useful strategy to grasp objects or anchor a body, especially when prolonged contact is desired. For passive suction cups, detachment requires manual delamination, which cannot occur autonomously. Active suction cups detach via equalizing pressure in the suction cavity with the surrounding environment, either by adding fluid (e.g., from a compressed air source) or reducing the cavity volume. While this detachment mechanism can be autonomous, it is inefficient, resulting in a net zero or loss of fluid. A more efficient detachment mechanism would enable multiple iterations of attachment and detachment without requiring additional fluid. To address this need, we designed a suction cup with a secondary release chamber embedded in the contact ring. The release chamber triggers delamination by deforming the shape of the contact ring. Through empirical testing, we found the optimal location and geometry of the release chamber. Our design allows for reliable detachment with a 5~mL decrease in release chamber volume, regardless of the adhesive suction force. Because the release chamber is a closed system, attachment and detachment results in net gain of fluid. Therefore, we propose a novel secondary benefit of adhesion via suction: harvesting fluid to power other pressure-driven soft robotic systems. and This ZIP archive includes CAD models for:
The exploded view of the suction cup assembly and the molds of all suction cup configurations shown in Figure 4 of the paper:
(b) Different release chamber locations
(c) Different membrane thicknesses
(d) Constant volume with varying release chamber areas
(e) Constant area with varying release chamber heights
(f) Constant height with varying release chamber areas
Xiangyun Bu, Yihao Geng, Siyuan Yin, Liyan Luo, Cameron A. Aubin, Talia Y. Moore (2025) "Release Chamber Enables Suction Cup to Delaminate and Harvest Fluid" IEEE RoboSoft.