We have designed and are building and commissioning a complete 1-meter prototype, including the instrumention and enclosure. Unlike the 0.4-meter class the entire telescope has been tailor designed and manufactured. The 1-meter class will be primarily used for the LCOGT science program, but we anticipate that some observing time will be available to education users.
The 1-meter prototype being tested in Goleta is being used to demonstrate its capabilities for Science Goals (acquire good absolute & precision relative photometry), and to validate all optical, mechanical, electrical and software functions prior to wider deployment.
Once the prototype has been fully tested at Santa Barbara, 1-meter telescopes will be deployed to Cerro Tololo, Chile, SAAO and Siding Springs, Australia. The enclosure, instruments, control servers and the telescope are all being commissioned, and have passed most of their test requirements. Six 1-meter telescopes are being assembled in our warehouses as of December 2011, with parts for 6 more on hand. Groundwork and Domes are already installed at CTIO in Chile and SAAO in South Africa, see eg. http://lcogt.saao.ac.za/ for a live view of site development work in South Africa.
Video
This video shows a schematic of an LCOGT 1-meter telescope responding rapidly to a request for observations. The telescope slews to the target and then tracks it. Simultaneously the dome rotates into alignment, both dome shutters open, and the mirror cover opens (you can see reflections in the mirror) so the telescope is ready to start imaging in the requested filters. Normally each telescope will already be open and observing, but this shows all the steps necessary to fulfill an observing request. The 1-meter telescopes can move from anywhere to tracking and observing any new target in 25 seconds or less.
1-meter Mount
The 1-meter mount is a scaled up version of the 0.4-meter mount. The basic concept of a reliable equatorial mount with C-ring remained while the detailed design changed significantly for the following reasons:
- Higher performance Specs;
- Experience with the 0.4-meter. What worked well, what didn't, etc;
- Greater safety requirements;
- Scaling issues with manufacturing;
- Interface with a different OTA for larger instruments
The main elements of the mount are:
- C-ring;
- Base;
- RA and Dec drives, which are similar to those used on the 0.4m telescopes, and controlled the same way
- RA sandwich, containing the drive-side and following rollers for the 2-m diameter C-Ring
- Crygenic cooling system.
The main elements of the Optical Tube Assembly (OTA) are:
- Steel Mirror Cell containing 18-point whiffle tree and central hub primary support system, forming the main load bearing structure for the OTA
- Lightweight Hextek Borosilicate mirrors polished and coated (Al overcoated with Quartz) by LZOS
- Roll cover and Hartmann screen just above the primary
- Primary stray-light baffle assembly
- Carbon Fiber truss assembly supporting invar secondary spider support
- 3-axis M2 assembly for focus and remote collimation
- Secondary stray light baffle assembly
- Support for science instrument in straight through cassegrain port, 0.8deg field of view
- The science imager uses a Fairchild 4K CCD with fast readout and flexible observing modes; 26-arcmin field of view with 0.4" pixels
- Support for 4 off-axis fixed ports for autoguiding, fast-photometry and fiber feed for a bench medium resolution spectrograph at each site
- We have developed a comprehensive embedded control system based on the Blackfin processor family, to enable networked control and telemetry of all mechanisms such as focus, collimation, filter wheels, covers and sensors such as temperature and position probes.
- The Blackfin architecture also enables us to design "smart" power modules to support power cycling and current monitoring of each sub-system.
The main elements of the Control System (common to all telescope classes) are
- a Java-based Telescope Control System (jTCS) utilizing the Java Agent DEvelopment (JADE) framework, providing:
- Astrometric agent and guiding based on the TPK kernel, using Astrometry.Net for automatic WCS fitting & Tpoint modeling
- axes control agents to servo on latest target coordinates
- agents to control all enclosure and telescope systems, including focus as a function of temperature and Zenith Angle
- agents monitoring IERS bulletins and to configure each telescope and focal plane
- agents for multiple instrument and guider selection, filter wheels, exposure and subsystem control for requested observations
- Proposal Observation Network Database (POND) to monitor observations from request to completion
- Flash reduced data available on-site for quick checks and quality monitoring
- ORAC pipeline to remove instrument signatures and derive source information to be stored in a database hosted by IPAC
- Telescope Scheduler to schedule (and re-schedule) observations across the network
