Smart sensor architecture for vital signs and motor activity monitoring of wheelchair´ users

The development of a smart sensor architecture for health status monitoring and daily motor activity of wheelchair users is considered. Modularity of solution and compatibility of the architecture with IEEE1451 standard for smart sensors were part of the requirements. Thus the work presents a microcontroller-based platform compatible with IEEE 1451.4 standard for vital signs and motor activity assessment of wheelchair users. The identification of the wheelchair user is done using the LF RFID technology through a RFID reader connected to the platform. The signals from unobtrusive sensors embedded in the wheelchair characterized by plug-and-play and auto-identification capabilities are acquired and primary processed at the platform level and transmitted using IEEES02.15.4 wireless communication protocol to a server application implemented in a host PC. Referring to the embedded sensors considered in the present approach, photoplethysmography, skin conductivity, and ballistocardiography are used for cardiorespiratory assessment while a 3D accelerometer is used for motor activity assessment. Elements of human-machine-interface (HMI) implementation and several experimental results are included in the paper.