19 February 2021 - Rick Wakeham
Featured in: Product information and OPTEX tech tips, Tech Tip, Intrusion detection
OPTEX Redscan series uses LiDAR technology which creates virtual detection planes when mounted horizontally and virtual walls when mounted vertically. Virtual walls can be vertical at 0 degree or can be tilted to provide best detection depending on the applications.
The theory behind vertical or tilted detection for LiDAR
Our laser sensors are constantly scanning the area by generating a laser beam and the resolution in outdoor mode is 0.25 degree for all models and 0.125 degree for the RLS-2020S in indoor mode only.
In a setting at 0 degree it provides a vertical virtual wall with a dense detection area detecting a crawling, squatting and walking person crossing the detection area. The object size is continuously analysed to provide best capture performance.
The 0 degree setting is the recommended setting for:
- façade protection
- assets protection
Tilting the angle of the Redscan enables three main functionalities:
- Detect a smaller moving object, so for instance a small crawling person with 25cm height
- Can detect a faster object such a person running quickly
- Can detect earlier, before the people reach the perimeter line
Detecting a person running
If someone is running fast through the vertical virtual wall, there might be a risk of missed detection. If the detection area is tilted by 30 degrees, this greatly improves capture performance, detecting very fast runners.
Detecting a smaller object person crawling
At 30 degree angle the REDSCAN can detect a smaller moving object. See example below, calculated with RLS-3060SH.
Pre-warning
When using the REDSCAN LiDAR in addition to a perimeter wall and fence, tilting the detection area allows to detect a person before reaching the perimeter line which can provide useful time to react and response. The caveat is, it creates a blind spot area between the wall/ fence and the laser virtual wall, so it is important to consider a double layer of detection.
To keep in mind
- For vertical virtual walls, the tilting angle should never exceed 45 degree (from 0 to 45).
- The tilting reduces slightly the detection range, for example when mounted at 4m the RLS-3060 series at 0 degrees will detect a crawling person up to 57m range. at 45 degrees the range is reduced to 53m. Please refer to the manual.
- For the RLS-3060 series, use the RLS-SB slant bracket to tilt the sensor.
- The RLS-2020 series is designed with a Multi-angle Alignment Shell Structure to facilitate several options. However, where additional tilt and mounting options are required consider using the multi-angle bracket part number 2020MAB, or RLS-AB.
- The position of the laser beam should always be verified using the Laser Alignment Checker part number LAC-1.