Scan Pattern Configuration

The ScanPattern service allows to configure the scan pattern, i.e. the laser scanning trajectory of the sensor. This way, the field of view, the number of scanlines, as well as the angle spacing (i.e. the point density on a scanline) can be set.

Please follow the Python Client Library Guide to install the Python package first.

Setting the scan pattern

The following code snippet can be used to set the scan pattern configuration. To this end, it utilizes the Set method of the service.

The configuration of the scan pattern directly defines the maximum frame rate of the point cloud stream.

import blickfeld_qb2
import math

scan_pattern = blickfeld_qb2.system.config.ScanPattern()

# Mirrors configuration for scan pattern trajectories
scan_pattern.vertical.field_of_view = 50 / 180 * math.pi
scan_pattern.vertical.scanlines_down = 36
scan_pattern.vertical.scanlines_up = 36

# Horizontal angle spacing for scanlines
scan_pattern.pulse.angle_spacing = 0.5 / 180 * math.pi

# Set scan pattern
with blickfeld_qb2.Channel(fqdn_or_ip="qb2-xxxxxxxxx") as channel:
    service = blickfeld_qb2.system.services.ScanPattern(channel)
    service.set(scan_pattern=scan_pattern)

Storing a scan pattern

Instead of the Set method in the code above, the Store method can be used to permanently store the scan pattern on the device to be later applied from the WebGUI.

with blickfeld_qb2.Channel(fqdn_or_ip="qb2-xxxxxxxxx") as channel:
    service = blickfeld_qb2.system.services.ScanPattern(channel)
    service.store(name="TestScanPattern", scan_pattern=scan_pattern)

Getting the currently applied scan pattern

The Get method is used to fetch the currently applied scan pattern configuration from the device.

import blickfeld_qb2

with blickfeld_qb2.Channel(fqdn_or_ip="qb2-xxxxxxxxx") as channel:
    service = blickfeld_qb2.system.services.ScanPattern(channel)
    response = service.get()
    print(response)

Output:

ScanPatternGetResponse(
    name='TestScanPattern', scan_pattern=ScanPattern(
        horizontal=ScanPatternHorizontal(
            field_of_view=1.483529806137085
        ),
        vertical=ScanPatternVertical(
            field_of_view=0.8726646304130554, scanlines_up=36, scanlines_down=36
        ),
        pulse=ScanPatternPulse(
            angle_spacing=0.008726646192371845
        ),
        frame_rate=ScanPatternFrameRate(
            maximum=7.366110801696777
        )
    )
)

Listing the stored scan patterns

The previously stored scan patterns can be listed with the List method.

import blickfeld_qb2

with blickfeld_qb2.Channel(fqdn_or_ip="qb2-xxxxxxxxx") as channel:
    service = blickfeld_qb2.system.services.ScanPattern(channel)
    response = service.list()
    print(response)

Output:

ScanPatternListResponse(
    named_scan_patterns={
        'TestScanPattern': ScanPattern(
            horizontal=ScanPatternHorizontal(
                field_of_view=1.483529806137085
            ),
            vertical=ScanPatternVertical(
                field_of_view=0.8726646304130554, scanlines_up=36, scanlines_down=36
            ),
            pulse=ScanPatternPulse(
                angle_spacing=0.008726646192371845
            ),
            frame_rate=ScanPatternFrameRate(
                maximum=7.366110801696777
            )
        ),
        ...
    }
)