title: A remote monitor of bed patient cardiac vibration, respiration and movement.
abstract: We have developed a remote system for monitoring heart rate, respiration rate and movement behavior of at-home elderly people who are living alone. The system consists of a 40 kHz ultrasonic transmitter and receiver, linear integrated circuits, a low-power 8-bit single chip microcomputer and an Internet server computer. The 40 kHz ultrasonic transmitter and receiver are installed into a bed mattress. The transmitted signal diffuses into the bed mattress, and the amplitude of the received ultrasonic wave is modulated by the shape of the mattress and parameters such as respiration, cardiac vibration and movement. The modulated ultrasonic signal is received and demodulated by an envelope detection circuit. Low, high and band pass filters separate the respiration, cardiac vibration and movement signals, which are fed into the microcontroller and digitized at a sampling rate of 50 Hz by 8-bit A/D converters. The digitized data are sent to the server computer as a serial signal. This computer stores the data and also creates a graphic chart of the latest hour. The person's family or caregiver can download this chart via the Internet at any time.
authors: Department of Health science, Hiroshima Institute of Technology, Hiroshima 731-5193 Japan. m160806@cc.it-hiroshima.ac.jp
authors: Koji
authors: K
authors: Mukai
authors: Yoshiharu
authors: Y
authors: Yonezawa
authors: Hidekuni
authors: H
authors: Ogawa
authors: Hiromichi
authors: H
authors: Maki
authors: W Morton
authors: WM
authors: Caldwell
mesh_terms: D000328:Adult; D001513:Beds; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D020407:Internet; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D012119:Respiration; D012985:Software Design; D013686:Telemetry / Q000295:instrumentation*; D055815:Young Adult