FLOWBIO’s hydration sensor is a wearable product developed for athletes to monitor fluid and sodium loss through sweat. It also tracks skin temperature, helping users manage hydration and recovery during training and competition.
FLOWBIO engaged our team having seen examples of i4PD's mechanical design support for wearable products. The main focusses of this project were to improve manufacturability, reliability, and robustness. The product needs to perform reliably in harsh outdoor environments, integrate with various strap types, and meet ingress protection standards (IP55), all while maintaining sensor accuracy and user comfort.
Product imagery / video courtesy of FLOWBIO
Designing for Real-World Use. The FLOWBIO device is intended for punishing and repeated use by athletes in demanding conditions. Our engineers selected polycarbonate (PC) for the fluidic components, a strategic decision that balances hydrophilic performance with UV stability and impact resistance. The mechanical design of the enclosure was shaped to fit securely on the arm or chest, with grip features and surface textures to prevent any slipping during movement.
Optimising for Manufacture. Initial prototypes used adhesive tape for sealing, but a thorough testing process revealed limitations. After revaluating the design, our team introduced a 'trench and tongue' fitment design, sealed by glue. This offers a more consistent and scalable solution for manufacture. The team also transitioned to a twin shot moulding process for the device's button, improving durability and giving a better bond to the device unit.
Refining User Interaction. The final design featured a flat button to prevent accidental activation, and a multi-colour LED placed above it for clear status indication. These refinements were guided by user feedback and practical testing.
Supporting Assembly and Tolerance Control. To ensure consistent sensor performance, i4PD provided a tolerance stack-up analysis exercise to guide the implementation of foam pads and guide ribs. These features help maintain the alignment of internal components and reduce the chances of variability during production.
The FLOWBIO sensor is a great example of how mechanical design support can elevate product performance and production readiness. i4PD’s support ensured that all details of the design were engineered for reliability, usability, and manufacturability.
