The Norfolk State University 24-inch Rapid Response Robotic Telescope at Fan Mountain (Rev. September 12, 2012)

Transcription

1 The Norfolk State University 24-inch Rapid Response Robotic Telescope at Fan Mountain (Rev. September 12, 2012) 1. Introduction Figure 1. The Norfolk State University RRRT Observatory at Fan Mountain. This manual gives general instructions for operating the Norfolk State University 24- inch Rapid Response Robotic Telescope (RRRT) at Fan Mountain with its observatory automation system, robotic control software, guide box, and CCD imager. The RRRT Observatory is a teaching and research facility of Norfolk State University, which owns the building and the telescope and leases observatory space on the mountaintop under a memorandum of understanding with the University of Virginia. The telescope and instruments are available for use by UVa for undergraduate and graduate student teaching and the research programs of faculty and their students. You should conduct your work with the utmost care, patience, and forethought, keeping in mind that the equipment is delicate, complex, and expensive to maintain. To minimize the potential for accidents, you should have a clear idea of your observing plan for the night, including the optimal observing times of your target and calibration 1

2 objects, lists of coordinates and finder charts, and an efficient plan for minimal changing of filters. Do not neglect to obtain the necessary set of bias frames, dark frames, and flat fields for calibration, or the rest of your data will be worthless. If anything in this manual is unclear, consult the TA or appropriate faculty member for clarification. As with all delicate equipment, NEVER force any moving part beyond reasonable and expected resistance. Always keep track of the telescope position in relation to the sky, dome, and objects within the dome. If you are operating the telescope from the observatory control room, go inside the dome room periodically to check on the status of the telescope and the dome. NEVER touch any optical element. Oils from your skin will permanently embed into glass surfaces and optical coatings. It is better to leave small amounts of dust on optical surfaces than to risk scratching or marring them with attempts at cleaning. If dust or dirt is a serious problem use the obstrouble mailing list to request cleaning of optics. If you are uncertain about any aspect of operating the telescope, or any other piece of instrumentation, STOP and ask someone. THINK BEFORE DOING. Home phone numbers: David McDavid ( ), Jim Barr ( ), Fan Mountain caretaker Nick Nichols ( ). In case of emergency don t hesitate to call, but please do not call unless it is absolutely necessary. 2. Description The RRRT is an equatorially mounted OGS (Optical Guidance Systems, Inc.) open-truss f/8.0 Ritchey-Chrétien optical system with a 24-in (0.6-m) aperture, a focal plane image scaleof42.3 mm 1, andacorrectedfieldof30, installedinoctober2007. Thecomputerized control system (TCS Pro MKS-4000 Servo) was developed by Software Bisque, Inc. and is described in the Bisque TCS and Paramount ME user manuals. The RRRT Observatory may be operated at several different levels of automation. The utility computer astronsu.astro.virginia.edu (Windows XP) is accessible through remote VNC connection by user RRRT0 and the instrument control computer rrrt.astro.virginia.edu (Windows XP) by user RRRT1. If operating the telescope remotely, the wireless webcam mounted on the southwest inside rim of the dome may be helpful for remote inspection of conditions in the dome. It is available at with login rrrt1view. Remote internet access to the RRRT is restricted to connections from the domains virginia.edu and nsu.edu. The telescope control system is built into TheSky6, a planetarium program which provides a graphical interface for finding objects and pointing the telescope. The telescope focuser is controlled by FocusMax automation software using RoboFocus as a driver. The CCD camera, filter wheels, and autoguider are controlled by MaxImDL5. The observatory dome, an AstroHaven clamshell, is controlled by the ASCOM POTH widget. Weather conditions are monitored by a Boltwood Cloud Sensor mounted on the northwest edge of the control room rooftop through the Clarity software interface. For many purposes a remote or on-site observer can operate the observatory and take data in computer controlled mode by running various combinations of these individual software applications. Detailed software documentation is on file in the observatory control room, in the online help files, and on the web. The ACP Observatory Control Software provides a higher level of control by integrating the separate pieces into a single automation interface or control panel with scripting capability and a built-in web server which enables remote observing and programmed image 2

3 acquisition through a web browser. An extensive Reference Guide for ACP is available on the web at Fully robotic, unattended operation of the observatory is made possible with ACP Scheduler, which takes control of ACP. The Scheduler maintains a database of observing Projects, periodically sorts the Project queue, and dispatches commands to ACP to check the weather, open and close the dome, acquire dusk and dawn flat fields and calibration frames, execute the planned observations, and write data and log files to disk on the rrrt PC. 3. Startup Procedure The observatory control software consists of many individual applications, most of which are intended to be controlled by local or remote scripts and to interact with each other as clients and servers. Since one application may require others to be running, the order in which they are started and connected (or stopped and disconnected) can sometimes have unexpected consequences and may result in some part of the system becoming unresponsive, causing a crash which may require stopping one or more programs with the Windows Task Manager and possibly rebooting the control computer before work can be resumed. The following startup procedure usually results in a fully functional observatory control system for the general user. For specific purposes, or for experienced observers needing a special configuration, individual applications and the system as a whole may be started up in many different ways. 1. Begin filling out a new nightly observing log in the RRRT Observing Log Notebook in the control room. Blank forms fan06log.pdf may be printed out from RRRT0 s Desktop on the astronsu PC. 2. Check power status and power up if necessary: (a) Two large UPS units (dome and other) ON. (b) Telescope control PC ON (rrrt.astro.virginia.edu). Login as RRRT1. (c) Auxiliary PC ON (astronsu.astro.virginia.edu). Login as RRRT0. (d) From the RRRT0 account on the astronsu PC, use the SnapLink home automation control program to check the status of the air conditioner in the dome and turn it OFF if necessary. i. Start SnapLink from the Windows Start Menu Panel shortcut (Fig. 2). ii. Enter the SnapLink password and Connect (Fig. 3). iii. Open the Temperature Panel (Fig. 4) and check that the Dome TSTAT mode is set to OFF. If it displays COOL, select the word COOL, then select OFF in control panel that pops up. (e) From the RRRT0 account on the astronsu PC, use the ibootbar network power appliance control program to turn Telescope and Camera power on and observatory pier Light off. Avoid transient surges by powering devices on or off individually one at a time. The Telescope outlet powers the telescope controller, focuser, and dew heaters. The Camera outlet powers the CCD camera and the TopBox. Wait about 30 seconds for the TopBox controller to initialize. In the 3

4 Figure 2. Startup menu shortcuts for RRRT0 on the astronsu PC. Figure 3. HAI SnapLink Startup Panel. dome you will hear a relay click, then the filter wheels and autoguider positioner will automatically move to their home positions. When you hear the sound of one of the filter wheels moving to its startup position (this is Filter Wheel 2 setting the V filter in place), initialization is complete. i. Start ibb-scu v1.5 from the Windows Start Menu Panel shortcut (Fig. 2). 4

5 Figure 4. HAI SnapLink Temperature Panel. ii. Select Dataprobe in the ibootbar Setup panel and login as rrrtpwr. (See Fig. 5.) Figure 5. ibootbar Setup panel Login mode. 5

6 iii. Select devices, one at a time, and use the ON and OFF buttons as necessary. (See Fig. 6.) Figure 6. ibootbar Setup panel Control mode. 3. Start Observatory Controls on the rrrt PC: Start applications from Windows Start Menu Panel shortcuts. (See Fig. 7). Program icons on the menu panel are arranged in order: (a) Start Clarity (weather monitor) (b) Start ACP (observatory control) (c) Start TheSky6 (telescope control): Telescope Link Establish, Confirm Find Home Now (d) ACP: Telescope Connect (dome will connect automatically) (e) Start Pipe connection watcher (allows monitoring of the TopBox driver s automatic adjustments of the autoguider focuser using JMISmartFocus; minimize this window during normal operation) (f) Start MaxImDL5 (camera control): View Camera Control Setup: Connect, Cooler On, check temperature SetPoint (-12C in summer, -20C in winter, -15C in fall and spring) (g) ACP: Camera Connect (h) Start FocusMax (telescope main focuser) (i) ACP: Weather Connect 6

7 Figure 7. Startup menu shortcuts for RRRT1. The observatory should now be up and running for control through ACP, or through the ACP web browser interface at 4. Start ACP Scheduler on the rrrt PC: The Scheduler is the top-level software component for fully automated (robotic) observing. Its function is to sort the project queue and dispatch work to ACP. When the Scheduler application is started, the dispatcher is not running until the Dispatcher Running checkbox on the Scheduler panel is selected. (a) From the Windows Start Menu Panel shortcuts (see Fig. 7), start the Scheduler. (b) Select the Dispatcher Running checkbox on Scheduler panel. When conditions are right to start observations, the Scheduler runs the Observatory Startup script, which (if necessary) will connect and unpark the telescope, verify that the camera is connected and cooled down, open the dome, and then begin automatic execution of projects in the project database. The most detailed interface to the Scheduler for status, submission of projects, and dispatcher control is only available from the Scheduler menu View Browser on rrrt from the running rrrt PC session with user RRRT1 or by remote login to this account on the rrrt PC through the VNC Server. Disabled projects may be enabled ( resubmitted ), enabled projects may be disabled, edited, and resubmitted, and new projects may be created and resubmitted regardless of whether the dispatcher is running or not. If projects are changed and/or resubmitted while the dispatcher is running, the dispatcher will simply re-sort the project queue. This interface is normally used only by the Observatory Operator, who checks and enters project request information submitted by users. (c) To enable GRB monitoring, start VOEvent Receiver from the Windows Start Menu Panel shortcuts. The VOEvent Receiver is a live socket connection to 7

8 listen for GRB alerts. If an alert for an observable GRB is received, any current activity of the Scheduler will be stopped and the Scheduler will automatically begin a pre-programmed observation sequence at the position specified by the GRB alert message. At the end of an observing session reverse these operations to leave the observatory in the desired state, finish filling out the Observing Log, and archive the data. 4. The TopBox Guide Box The RRRT TopBox (Figs. 8 and 9) is an automated combination filter wheel/polarimetry module and offset guider. It consists of a single enclosure containing a diagonal pickoff mirror mounted on a motorized stage, followed by two filter wheels and the mount for an imaging CCD camera. The first filter wheel holds a pair of Savart plate polarization analyzers P1 and P 2, and the second filter wheel holds bandpass filters (a standard Johnson-Cousins UBVRI photometry filter set). The 10 combinations of the 5 bandpass filters and the 2 polarizers, the 5 bandpass filters without polarizers, and one Empty position make up the 16 filter positions available for selection in MaxImDL5. Figure 8. The RRRT TopBox under construction. Figs. 10 and 11 show a side view and a front view of the TopBox mounted on the telescope, with design drawings for comparison. WhenatargettobeimagedbyACPorACPSchedulerrequiresautoguiding,theTopBox searches the GSC catalog for a guide star within the guider s range of motion, moves the guider stage into position, and adjusts the guider focuser to match the main telescope focus for the selected filter and the guide star position in the curved off-axis focal surface. The pickoff mirror is attached to a focuser with an autoguider camera which may be interchanged with a video camera or a standard eyepiece for visual observing without disturbing the focal plane detector setup. The two Savart plates are oriented at 45 degrees to each other in the converging beam to produce a pair of optically corrected double images 8

9 Figure 9. The RRRT TopBox mounted on the telescope. yielding independent measurements of both linear Stokes parameters for point sources in the CCD field of view by differential photometry. The system is designed to be mounted on the tailpiece of the RRRT to place either an SBIG STL-1001E or an Apogee Alta U42 CCD camera in the optimum focal plane, with options to move the guiding and polarimetry optics out of the beam for unguided or direct imaging. The control electronics are mounted on a subpanel housed in a utility cabinet which is mounted on the west side of the telescope pier (Fig. 12). Three stepper motor drivers on a single daisy-chained serial control line operate the two filter wheels and the linear slide which carries the autoguider assembly, and another driver unit on a second serial control line operates the autoguider focuser. 9

10 Figure 10. TopBox side views on the telescope and in design. 10

11 Figure 11. TopBox front views on the telescope and in design. 11

12 Figure 12. The TopBox control electronics cabinet. 12