CBP User Guide¶
The CBP has two directions for axial movement, the azimuth (side-to-side) and altitude (bottom-to-top). It also allows for up to five masks to be added as a means of characterizing beam projection. Limits are in place for each axis to prevent damage to the device. The CBP also has the ability to be parked, where the altitude is at -70 degrees and the motors cannot be moved. This ability can be manually commanded, but is automatically triggered if an internal battery source detects that the power has been lost for more than ~3 seconds.
CBP Interface¶
A link to the SAL API can be found at the top of the index.
The main commands that will likely be used are
cbp:commands:moveazimuth
cbp:commands:movealtitude
The relevant telemetry includes
cbp:telemetry:altitude
Example Use-Case¶
Starting the CSC
from lsst.ts import salobj
domain = salobj.Domain()
cbp = salobj.Remote(name="CBP", domain=domain)
await cbp.start_task
Un-parking the CSC
await cbp.cmd_park.set_start(park=False, timeout=10)
Moving the CBP in azimuth
await cbp.cmd_moveAzimuth.set_start(azimuth=30, timeout=10)
Moving the CBP in altitude
await cbp.cmd_moveAltitude.set_start(altitude=45, timeout=10)
Changing CBP’s mask.
await cbp.cmd_changeMask(mask="1")
Getting telemetry from the CBP
azimuth = await cbp.tel_azimuth.aget(timeout=2)
altitude = await cbp.tel_altitude.aget(timeout=2)
Clean up
await domain.close()