Method and apparatus for monitoring and estimating the awakeness of a person

Claim 1

An apparatus for monitoring and estimating a person's wakefulness and, thereby, drowsiness, comprising at least one stationary pressure sensitive means (2, 3, 4) which is adapted to contact at least a portion of said person's (1) body, and to generate an electric signal on its output terminal in response to said person's body movements relative to same, a detector/filter circuit (5), connected to the output terminal of said at least one stationary pressure sensitive means (2, 3, 4), and adapted to separate, from said electric signal, signals corresponding to the duration and magnitude of true body movements, to the amplitude of heartbeat-related body movements as a function of rate, and to the amplitude of respiration-related body movements as a function of rate, and output these separated signals on corresponding output terminals, a first calculation and comparison circuit (8, 11) which is adapted to receive, on its input terminal, said signal corresponding to true body movements, to calculate the duration and magnitude of the true body movements as well as the time interval between same, and to compare these calculated values with previously calculated corresponding values to determine possible changes, a second and a third calculation and comparison circuit (6, 9 and 7, 10, respectively) which are adapted to receive, on their input terminals, said signal corresponding to heartbeat-related and respiration-related body movements, respectively, to calculate the amplitude of every heartbeat-related and every respiration-related body movement, respectively, as well as the time interval between at least two successive heartbeats and respirations, respectively, and to compare these calculated values with previously calculated corresponding values to determine possible changes, a correlator (12), connected to the the output terminals of said three calculation and comparison circuits (6, 9; 7, 10; 8, 11), and adapted to correlate heartbeat-related and respiration-related changes with true body movement changes, a threshold detector circuit (13), connected to the output terminal of the correlator (12), and adapted to compare the resulting change with a preset wakefulness threshold, and an alarm device (14), connected to the output terminal of the threshold detector circuit (13), and adapted to trigger alarm when the preset threshold is reached as an indication of a reduced degree of wakefulness.

Claim 2

An apparatus for monitoring and estimating a person's wakefulness and, thereby, drowsiness, comprising at least one stationary pressure sensitive means (2, 3, 4) which is adapted to contact at least a portion of said person's (1) body, and to generate an electric signal on its output terminal in response to said person's body movements relative to same, a detector/filter circuit (5), connected to the output terminal of said at least one stationary pressure sensitive means (2, 3, 4), and adapted to separate, from said electric signal, signals corresponding to the duration and magnitude of true body movements, to the amplitude of heartbeat-related body movements as a function of rate, and to the amplitude of respiration-related body movements as a function of rate, and output these separated signals on corresponding output terminals, a first calculation and comparison circuit (8, 11) which is adapted to receive, on its input terminal, said signal corresponding to true body movements, to calculate the duration and magnitude of the true body movements as well as the time interval between same, and to compare these calculated values with previously calculated corresponding values to determine possible changes, a second and a third calculation and comparison circuit (6, 9 and 7, 10, respectively) which are adapted to receive, on their input terminals, said signal corresponding to heartbeat-related and respiration-related body movements, respectively, to calculate the amplitude of every heartbeat-related and every respiration-related body movement, respectively, as well as the time interval between at least two successive heartbeats and respirations, respectively, and to compare these calculated values with previously calculated corresponding values to determine possible changes, a correlator (12), connected to the the output terminals of said three calculation and comparison circuits (6, 9; 7, 10; 8, 11), and adapted to correlate heartbeat-related and respiration-related changes with true body movement changes, a threshold detector circuit (13), connected to the output terminal of the correlator (12), and adapted to compare the resulting change with a preset wakefulness threshold, and an alarm device (14), connected to the output terminal of the threshold detector circuit (13), and adapted to trigger alarm when the preset threshold is reached as an indication of a reduced degree of wakefulness.

Claim 10

A method of monitoring and estimating a person's wakefulness and, thereby, drowsiness, comprising the steps of: generating an electric signal in response to said person's body movements relative to at least one stationary pressure sensitive means which contacts at least a portion of said person's body; separating said electric signal into signals corresponding to duration and magnitude of true body movements, amplitude of heartbeat-related body movements as a function of heart rate, and amplitude of respiration-related body movements as a function of respiration rate; measuring and comparing the duration and magnitude of the true body movements and the time-interval between the true body movements with previously measured corresponding values to determine possible changes; measuring and comparing the amplitude of every heartbeat and respiration-related body movement and the time-interval between at least two successive heartbeats and respirations with previously measured corresponding values to determine possible changes; correlating heartbeat and respiration-related changes with true body movement changes to establish a resulting change; comparing the resulting change with a preset wakefulness threshold; and triggering an alarm when the threshold is reached as an indication of a reduced degree of wakefulness.

Claim 11

A method of monitoring and estimating a person's wakefulness and, thereby, drowsiness, comprising the steps of: generating an electric signal in response to said person's body movements relative to at least one stationary pressure sensitive means which contacts at least a portion of said person's body; separating said electric signal into signals corresponding to duration and magnitude of true body movements, amplitude of heartbeat-related body movements as a function of heart rate, and amplitude of respiration-related body movements as a function of respiration rate; measuring and comparing the duration and magnitude of the true body movements and the time-interval between the true body movements with previously measured corresponding values to determine possible changes; measuring and comparing the amplitude of every heartbeat and respiration-related body movement and the time-interval between at least two successive heartbeats and respirations with previously measured corresponding values to determine possible changes; correlating heartbeat and respiration-related changes with true body movement changes to establish a resulting change; comparing the resulting change with a preset wakefulness threshold; and triggering an alarm when the threshold is reached as an indication of a reduced degree of wakefulness.

Claim 13

A method of monitoring a person's wakefulness, comprising the steps of: locating a person's body adjacent plural, stationary, pressure-sensitive sensors; generating an electric signal with said plural sensors responsive to body movements of said person; separating said electric signal into plural signals corresponding to duration and magnitude of body movements, amplitude of heartbeat-related body movements, and amplitude of respiration-related body movements; measuring and comparing the duration and magnitude of the body movements and the time-interval between the body movements with previously measured corresponding values to determine possible changes; measuring and comparing the amplitude of every heartbeat and respiration-related body movement and the time-interval between at least two successive heartbeats and respirations with previously measured corresponding values to determine possible changes; correlating heartbeat and respiration-related changes with body movement changes to establish a resulting change; and establishing a degree of wakefulness based on said resulting change.

Claim 14

A method of monitoring a person's wakefulness, comprising the steps of: locating a person's body adjacent plural, stationary, pressure-sensitive sensors; generating an electric signal with said plural sensors responsive to body movements of said person; separating said electric signal into plural signals corresponding to duration and magnitude of body movements, amplitude of heartbeat-related body movements, and amplitude of respiration-related body movements; measuring and comparing the duration and magnitude of the body movements and the time-interval between the body movements with previously measured corresponding values to determine possible changes; measuring and comparing the amplitude of every heartbeat and respiration-related body movement and the time-interval between at least two successive heartbeats and respirations with previously measured corresponding values to determine possible changes; correlating heartbeat and respiration-related changes with body movement changes to establish a resulting change; and establishing a degree of wakefulness based on said resulting change.