ACU Agent: sun-safe path failure when near elevation limit #744
Description
(From report in simonsobs/scheduler#83 )
@kmharrington reported schedule failure on SATP1, as scan was starting up. ACU log has:
2024-08-20T11:43:10+0000 Requested position: az=326.76375402860003, el=48.0
...
2024-08-20T11:43:14+0000 Moving to start position, az=326.7594, el=47.9997
2024-08-20T11:43:14+0000 No Sun-Safe moves could be identified!
2024-08-20T11:43:14+0000 generate_scan:226 No Sun-Safe moves could be identified!
The position is totally sun-safe. The failure basically arises because el=47.9997 (no doubt the "current elevation") is below the minimum elevation of el=48. So it can't find a sun-safe path, covering this ~arcminute, that lies entirely at el>=48.
The best fix is probably to clip the "where am I" measurement to the permissible range limits, if close enough.