Patent ID: 6361508
Filing Date: 2002-03-26
Classification: A61B

Abstract:
A device for monitoring the activity of an individual to provide an alarm for detecting anomalous activity by the individual, comprising:a sensor adapted to simultaneously and continuously measure acceleration in three orthogonal axes and to generate a voltage output that is linearly proportional to the amplitude of detected acceleraton by the individual in each axis; interface electronics to generate a first reference bias voltage Vref1 for each axis of said sensor; amplifier circuit for defining a user adjustable second reference voltage Vref2; amplifier circuit for amplifying each voltage output, and for continuously comparing each voltage output to said second reference voltage to produce a digital signal defining a single event; a microcontroller for receiving said digital signal, said microcontroller being programmed to discriminate between normal activity and anomalous activity by identifying a continuous series of events within sequences of preselected time intervals and sending an alarm signal upon detection of said anomalous activity; an alarm for receiving said alarm signal and signaling an alarm; and the microcontroller conserving power when no events are detected.