Non-Invasive Sensing of Cardiobilistram, Respiration, Snoring, Body Movement and Coughing of a Patient on the Bed

This paper describes a new type of health monitoring sensor that can be used at hospital as well as at home. The sensor non-invasively and non-restrictively measures human bio-signals of a patient on a bed, that can be used to estimate the stage of sleep.An air mattress laid out on the bed, a fine pressure sensor that detects the pressure of air in the air mattress and filters are the components of the non-invasive sensing system. The human body movements due to such as the cardiobilistram, respiration, snoring, turning over and coughing directly influence to the pressure and the causes of the movement can be discriminated by the proper filtering.Here we investigate the pneumatic characteristics of the air in the mattress via a mathematical model and show the effective filtering to eliminate the ill pneumatic characteristics and further to discriminate the changes due to various body movements. The important bio-signals from a sleeper whose sleeping posture was arbitrary were acquired without any disturbances.