daviteq Lidar People Counter, Manual

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DB:
Dead band = 30 mm (This is a short range in front of the ultrasonic sensor can’t measure distances)
H:
The height from sensor head to trashbin bottom (Inner surface)
D:
The value of LEVEL_MM parameter. (Distance from sensor head to trash surface)
L : The value of LEVEL_THOUSANDTHS parameter. (Ranging 0 ‰ to 1000 ‰)
How to determine H value?
Method 1:
Based on the design drawing of the trash bin or actual measurement
Method 2:
Read the sensor's measurement value when the trash bin is empty (L0). Then H = L0
How to determine the new coefficients A and B?
The calibration formula is L = a x D + b.
Calibration at 2 points: L=0(‰) when D=H and L=1000(‰) when D=DB
Therefore, the new coefficients A and B must be configured according to the formula:
After that, use the offline tool or downlink to configure A & B to the sensor.
Note: a1, b1 of sensor must be as default when use Method 2. (Default value a1=1, b1=0)
A = 1000 / (DB - H)
B = (1000 x H) / (H - DB)
4. Application notes for the Daviteq ULA ultrasonic