Reliability of the algorithm relies on the accuracy of the setup which detects the distance between the sensor and the
floor. This can be ensured only if nothing (e.g. no obstacle or static object) blocks the front and back FoVs. To assess if
a setup is reliable, a significant number of distances can be measured with the sensor. Then, a histogram diagram can
be established to confirm that the sensor is correctly set up and that no target is within its FoVs.
A threshold needs to be defined, which is achieved after having ranged on the flooring material over a significant
number of samples. In fact, the threshold should be chosen so that all the measured distances (when ranging the floor)
are greater than this threshold. We recommend that at installation of the application, an autocalibration routine is
launched to calculate the threshold. This is because flooring material can be different in many locations.
Figure 6. People counting at 2345 mm distance from the floor. The distance between the sensor and the floor is 2345
mm, and as the minimum distance measured by the sensor is 2290 mm, the threshold is thus less than 2290 mm.
Note: This calibration should be performed in the worst ambient light conditions, to maximize the jitter and obtain a
threshold that is relevant to all possible ambient lighting conditions the counting setup is exposed to.
Hi-Byte is error code
Error code
Description
0
No error
1
Just exchange the sensor module but node has not been reset ==>
please take out the battery for 20s then install it again to reset node to
recognize the new sensor module
2
Error, sensor port M12F shorted to GND
3
Error, sensor port M12F shorted to Vcc
4
Error, sensor port M12F shorted each other
Lo-Byte is sensor type
Error code
Description
0
No error
1
Just exchange the sensor module but node has not been reset ==>
please take out the battery for 20s then install it again to reset node to
recognize the new sensor module
2
Error, sensor port M12F shorted to GND
3
Error, sensor port M12F shorted to Vcc
4
Error, sensor port M12F shorted each other
6.2 Status bytes of sensor Node
6.3 Add sensors node to Co-ordinator WS433-CL
