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Fall detection algorithm

The research on the principle of fall detection is mainly to find the acceleration change characteristics of human body during the fall. Fig. 5 shows the curves of acceleration during different movements, including (a) going upstairs and (b) stepping.

Go downstairs, sit down,

Stand up. The red curve is the Y-axis (vertical direction) acceleration curve, which should be-1g at normal rest; The black and yellow curves are the X axis (front-back direction) and the Z axis (left-right direction) respectively.

Acceleration curve, its normal static state should be 0g; The green curve is the vector sum of three-axis acceleration, which should be+1g at normal rest.

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