October 16, 2021
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“Anzen” is a FPGA-based smart fall detector and prevention belt integrated with a triaxial accelerometer which will detect a person falling and immediately trigger a local alarm system to alert nearby people regarding a subject’s fall. 

The salient features of our proposed system are: 


– Setup a threshold acceleration voltage which will differentiate between a fall case and Activities of Daily Living (ADL). 
– Detects any falling scenario for 170ms~220ms. 
– Trigger an alarm once a fall event is identified and alert others in the vicinity. 

The FPGA device that was used for the testing purpose was Cyclone III (Intel Quartus Prime). The synthesizable hardware descriptive code was written using VHDL (ModelSim).

The designed digital circuit has been able to detect an ADL event and can also identify a fall event. On a holistic level, the proposed system operates as follows:


– Count the number of high edges of each of the three signals of the triaxial accelerations within the defined time measurement window
– If the RMS value of the number of edges is higher than the lower-bound threshold but lower than the higher-bound threshold then it is an ADL event.
– If the RMS value of the number of edges is higher than the higher-bound threshold then it is a fall event, and an output signal is passed to the alarm (buzzer).

anzen