Analytical modeling for suction cup designs for skin-interfaced wearable devices

Clinical Snapshot

Key Findings

• P Value: Not applicable — no statistical hypothesis testing performed

• Effect Size: Not applicable — theoretical modeling study; no effect size in the clinical sense. The ring suction cup design is reported to offer optimised suction performance compared to the cone design based on derived scaling laws

• Primary Outcome: Explicit analytical formulas derived for deformation and attachment force of cone and ring suction cups as functions of geometry parameters, material properties, maximum push-down displacement, and subsequent pull-up displacement

• Nnt Or Sensitivity: Not applicable — engineering modeling study. Key outputs are scaling laws and closed-form design equations relating suction force and deformation to geometric and material parameters

• Confidence Interval: Not reported — theoretical study; no statistical confidence intervals provided

Clinical Application

The analytical models are immediately applicable to device engineers designing suction-based wearable mounts. Clinical feasibility of suction-mounted devices themselves requires subsequent empirical validation in human subjects across diverse skin types, body locations, and wear durations before clinical deployment. The models reduce the design iteration burden but do not replace clinical testing. Australia has a growing wearable health technology sector supported by the Digital Health Agency and CSIRO. Wearable biosensors are increasingly relevant to RACGP-endorsed remote monitoring programs, particularly for chronic disease management in rural and remote communities where in-person monitoring is limited. The TGA regulates wearable medical devices under the Therapeutic Goods Act 1989; any suction-based device would require TGA conformity assessment before clinical use. PBS listing of associated monitoring services (e.g., continuous glucose monitoring consumables) creates a regulatory and reimbursement pathway context. Skin health considerations are particularly important in Indigenous Australian populations, where skin infections and dermatological conditions are prevalent, making atraumatic device mounting clinically significant. Australian climate conditions (heat, humidity, high sweat rates) are directly relevant to the moisture-related limitations the authors acknowledge. Patients requiring continuous or prolonged skin-worn biosensing devices, including cardiac monitoring (ECG patches), continuous glucose monitoring, electromyography, photoplethysmography, and multimodal physiological monitoring wearables. Potentially relevant for neonatal monitoring, elderly care, and remote patient monitoring programs.

Abstract

Stable mounting is a central requirement for skin-interfaced wearable biomedical devices, because accurate and long-term measurements with clinical utility typically demand intimate contact with the skin, whereas practical use also requires gentle removal to minimize skin irritation and damage. Existing mounting strategies often struggle to satisfy these competing requirements simultaneously, especially under prolonged wear or in the presence of sweat and moisture. Suction-based mounting has recently emerged as a promising alternative because it can provide strong, reversible, and adhesive-free attachment, yet its underlying mechanics remain insufficiently understood. Here, we establish analytical models for the deformation and force of suction cups in a fully explicit form, covering both the cone suction cup and an optimized ring suction cup design. Unlike previous approaches that rely on indirect quantities such as the pressure difference and contact radius, which are not available before experiments and therefore cannot serve as controllable design variables, the present framework yields direct relations between suction performance and geometry parameters, material properties, and loading conditions, including the maximum push down displacement and the subsequent pull up displacement. The resulting formulas agree closely with accurate numerical solutions and lead to compact scaling laws that clearly identify how geometry and material parameters govern suction performance. These results provide a quantitative and physically transparent foundation for the design of suction-based mounting strategies in wearable devices.

References

1. 1.Li, S., Rogers, J. A., & Huang, Y. (2026). Analytical modeling for suction cup designs for skin-interfaced wearable devices. Proceedings of the National Academy of Sciences of the United States of America. https://doi.org/10.1073/pnas.2614670123