Development of Hybrid Bed-Chair Assistive Device with Non-contact Vital Sensor

This study aims to design a hybrid bed-chair assistive device with non-contact heart rate sensor for patients with mobility impairments. The novel mechanical design includes a dockable bed and wheelchair. The proposed design can assist conveniently caregivers in completing bed-chair transfer work. In addition, the subsidiary functions include the re-position function, bed rotation function, and lavatory function. Through using algorithms of face detection, blind source separation and FFT, the proposed non-contact image based heart rate detection can reduce the limitation of vital measurement. The simulation of the finite element method verifies that the proposed design satisfies the design requirements. The pressure analysis of the seat interface is used to determine the material and specifications of the seat cushion. The empirical experimental result of heart rate detection validates the correlation coefficients between the non-contact method and contact method reach 0.93.