Gesture and Motion Evaluation Kits (Digital) USEQMSK_____00
The above information is believed to be correct but does not purport to be all inclusive and must be used only as a guide.
© KEMET Electronics Corporation • KEMET Tower • One East Broward Boulevard
Fort Lauderdale, FL
33301 USA • 954-766-2800 • www.kemet.com
12
Window Size
•
Window width in samples used to detect event.
Larger window allow slower gestures, smaller rejects them.
•
Range:
10 to 2,000
•
Typical:
400
Detection Threshold
•
How high the peak value has to be before recognised for gesture.
•
Range:
1 to 20
•
Typical:
3
The same ASIC, Wake-Up and System settings are available within the presence section as
in the gesture detection section.
6.2
Proximity Algorithm
The algorithm used for a presence being detected is an analysis of the rate of change of the
signal. A group of 3 data points are averaged and then the following 3 data points averaged.
The averaging reduces the effect of noise on the algorithm, more data points could be used
to improve resistance to noise but that would be dependent on the location of the device in
the end application.
These two averaged values are then used to determine the rate of change of signal by
differentiating with respect to time, or the spacing between data points which in this case is
three.
The detection threshold affects the required rate of change of signal to give a positive motion
detection event. The initial value of 20 give good results but again this can be adjusted
depending on the application
’s environment and optical setups that might be in use.
