Personal event monitor with linear omnidirectional response

摘要

A monitor device for monitoring the activity of an individual to provide an alarm for anomalous by the individual. The device includes a triaxial accelerometer adapted to measure simultaneously measure acceleration in three orthogonal, linear axes and generate a voltage output identifying the amplitude and frequency of detected motion by the individual in each axis. Also included is interface electronics for receiving the voltage outputs and buffering the voltage outputs to generate a first reference voltage for each axis of the accelerometer. Amplifier electronics amplifies each voltage output and compares each voltage output to the first reference voltage to produce a digital signal. A microcontroller receives the digital signal to compare it to an adjustable second reference voltage. The microcontroller is programmed to discriminate between normal activity and anomalous activity by identifying sensor activity within sequences of preselected time intervals and sending an alarm signal upon detection of the anomalous activity. An alarm for receiving the alarm signal and signaling an alarm completes the device.