addition, without any staff available to press
buttons when something minor needs resetting, BFO also includes the provision for remote reset capabilities.
Figure 2.
TBAD receiver on the top
ring of the Gemini North
telescope in Hawai‘i.
A complex software sequence for dome
closing was developed at the lowest level
(Programmable Logic Controllers). This new
feature avoids relying on computers to perform one of the most critical tasks identified
when we defined our telescope and instruments safety requirements — the autonomous closing of shutters and vent gates.
The electronics that control the primary mirror covers and their mechanisms are also being upgraded to make their operation not
only safer for the primary mirror but also
more reliable. This improvement will allow
us to open and close the covers remotely
from the base facility as well.
For instance, Gemini North can now remotely
turn systems on and off that could previously only be controlled at the telescope facility.
Also, Gemini has long used human spotters
to detect aircraft and alarm telescope operators of possible accidental illumination from
the Gemini laser. This system became unworkable under the new operational model,
so we reached out to our colleagues at the
W.M. Keck Observatory and joined in a very
successful collaboration that resulted in an
automated Transponder-Based Aircraft Detector (TBAD). Developed by Keck and Tom
Murphy at the University of California, TBAD
can monitor aircraft transponder signals, determine whether the craft are too close to
the area of laser propagation, and, if so, send
a command to close the laser shutter without any human intervention.
Our Gemini North generator power transfer
system also needed attention, so we modified and improved it to remotely, and autonomously, close the dome if a power outage
occurs. The system will also work even if the
network connection to the summit is lost. In
October 2015
To make the work environment more suitable for nighttime operations at the base facility, we’ve modified the control room so it
can accommodate additional monitors and
network connection ports, provide better
lighting, and support additional security. Finally, the telescope facility is being upgraded to improve its dialup notifications infrastructure and security system, as well.
Trial Run Begins in Hawai‘i
BFO has already entered its trial operations
phase at Gemini North. We have completed
internal testing of most of the critical work
packages and followed that with user testing and verification. As this issue goes to
e-press the products and work of the BFO
team are being tested as an orchestrated
collection of subsystems.
For the first time, on the night of September
8-9, 2015, a full test of the remote observing
capabilities at Gemini North was successfully completed operating in “base mode” while
the night crew was still at the telescope. Over
GeminiFocus
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