Enhancing performance and reducing wearing variability for wearable technology system-body interfaces using shape memory materials

Advancements in e-textiles, sensors, and actuators have propelled wearable technologies toward wide-spread market use, however the physical interface between these technologies and the human body has remained a functional challenge. Prior research has found that system-body interface challenges produce wearing variability, or variation in system placement, orientation, and tightness in relation to a body both between use trials and between users, resulting in large variation and deterioration in system performance. We break down the mechanics of common system-body interface challenges through a summary of design principles critical to any system interfacing with the human body. Additionally, we present an active interface based on shape memory materials that dimensionally adapts to its user's dimensions. An experimental investigation of these active system interfaces considers the impact of design variables often overlooked in the design process. Recommendations are provided to optimize interfaces for the requirements for a given wearable technology. Additionally, we illuminate methods to reduce wearing variability for a range of users to produce consistent system-body interaction across a user population. Through these active interfaces, we advance a broad range of wearable technologies, including wearable sensing, motion tracking, haptics, and wearable robotic devices.