daviteq Lidar People Counter, Руководство пользователя

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Daviteq Optical Sensing Technologies
Daviteq Lidar People Counter is a sensor with static lidar sensor with advanced and ultra-low-power MCU to perform
the counting algorithm.
To detect a person passing thru the gate, it uses lidar to measure the distance from the sensor to the object. As the
changes in distance, it will understand a person passing thru the gate. Moreover, it can distinguish the direction of
movement.
Precise counting with ultra-low-power to save energy is a big challenge with Lidar technology. Therefore, Daviteq
engineers had a smart decision to put the PIR sensor so that the sensor can wake up to count when there is human
reach the sensor, in the Field of view (FOV) of the PIR Sensor. When there is no moving human body in the FOV of the
PIR sensor, the sensor will go to sleep mode for energy saving. When it detects the moving human body, it will wake
up immediately to count people, the delay time of wake up is about
20ms.
When there is no moving human body, it will fall back to sleep mode within 20ms.
Counting people with this Lidar sensor consists of using the multiple zones of the sensor receiving area, and
configuring it with two distinct fields of view (FoV), to alternatively get a ranging distance from them and consequently
recognize the movements of a person. Using this method, the number of people occupying a meeting room, accessible
from reasonably narrow access, is known at all times by detecting the entrances and exits of the attendees.
By measuring and analyzing the distances of targets within the FoVs of a front and back zone (see figure below), an
algorithm can detect the direction a person crosses the area under the two FoVs. This algorithm "understands" that
someone is under one of the FoV as long as the distance measured by the sensor under this FoV is between 0 and a
threshold value specified in mm.
From a timing perspective, the sensor alternatively ranges on each of the two zones, for a very short period of
milliseconds. It is possible to determine in which direction a person crosses the area, depending on in which order this
person has been detected in the two zones, as shown in the figure below.
- The sensor will measure the distance from the sensor (on the ceiling) to the floor, when there is an obstacle, the
person is under the sensor, the sensor will measure the distance from the sensor to the obstacle, and that person =>
Daviteq LPC Lidar People Counter
- Measurement Principle
1. Overview
2. Detail measurement principle
Dist_threshold mechanism