Seola Lee, Andrew Akerson, Roham Pardakhtim, Ehsan Hajiesmaili, Katie Rhodes, Zidong Li, Andrew A. Stanley, Amirhossein Amini, D. Piazza, Chiara Daraio, Tianshu Liu
Wearable electronics are essential for health monitoring, haptic feedback, and human-computer interaction. However, maintaining stable contact with skin remains challenging due to its softness, roughness, and variability across body sites. Conventional solutions such as grounding bands or adhesive tapes often suffer from contact loss and limited repeatability. Suction-based adhesives offer a promising alternative by generating negative pressure without tight compression or chemical adhesives, but most designs assume rigid surfaces and overlook skin mechanics. Inspired by traditional cupping therapies, we introduce a suction adhesive system that attaches to diverse skin regions through elastic deformation and recovery. Using analytical modeling, simulations, and experiments, we develop a mechanics-based framework that links suction performance to cup geometry, substrate compliance, and interfacial adhesion. We show that wide, flat cups are effective on rigid surfaces but fail on soft substrates, while narrow, tall cups maintain recoverable volume and strong adhesion. To improve sealing on rough, dry skin, we introduce a soft, tacky interfacial layer guided by contact mechanics. Our design principles enable robust attachment of motion sensors, haptic actuators, and electrophysiological electrodes across diverse anatomical regions, offering a versatile, skin-friendly platform for next-generation wearable electronics.