The software framework for queue scheduling at the MMT Observatory (MMTO) is presented. This framework is part of the MMTO’s Observatory Manager (OM) that handles queue scheduling and many other observatory-related activities. The OM is divided into four overall components: 1) the “Web Frontend”, 2) the “REST API”, 3) the “Web Framework”, and 4) the “Scheduler Backend”. This paper emphasis the Scheduler Backend, which builds on the Python Astropy/Astroplan library with several new user-defined constraints and a custom sequential scheduler. These new constraints form an integral role in capturing the scheduling policies and priorities of the MMTO. The Scheduler Backend service can be run in two modes: 1) a “dispatcher” mode where observing blocks (OB’s) are ranked for a specific observing time, and 2) a “scheduler” mode where all OB’s are scheduled for the duration of the queue observing run. The dispatcher can be run multiple times throughout the night, as needed. The scheduler is typically executed once daily after sunrise after all data is collected for the night. Results from the dispatcher and scheduler are posted to a centralized Redis server for real-time monitoring of computing status and to relational databases for later review. Performance and optimization issues are discussed.
The MMT Observatory (MMTO) initiated a series of coating process improvement projects after an issue with the coating system in 2010 resulted in blemishes on the 6.5m primary mirror coating. Formally started in 2013, these projects focused on four major tasks: 1) development of a software-based system to control the tungsten filament power sources, 2) characterization of an integrally wound tungsten and aluminum filament, 3) prevent stray molten aluminum droplets from contacting the isolation membrane separating the high and rough vacuum sections of the system, and 4) assemble a coating facility capable of performing full-scale system testing. The completion of these projects was realized with the successful re-aluminization of the MMTO primary mirror in 2016. With a focus on the implementation of the process improvements, the present state of the MMTO coating system is described along with data from the 2016 realuminization.
This study investigates the software automation and control framework for the MMT thermal system. Thermal-related effects on observing and telescope behavior have been considered during the entire software development process. Regression analysis of telescope and observatory subsystem data is used to characterize and model these thermal-related effects. The regression models help predict expected changes in focus and overall astronomical seeing that result from temperature variations within the telescope structure, within the primary mirror glass, and between the primary mirror glass and adjacent air (i.e., mirror seeing). This discussion is followed by a description of ongoing upgrades to the heating, ventilation and air conditioning (HVAC) system and the associated software controls. The improvements of the MMT thermal system have two objectives: 1) to provide air conditioning capabilities for the MMT facilities, and 2) to modernize and enhance the primary mirror (M1) ventilation system. The HVAC upgrade necessitates changes to the automation and control of the M1 ventilation system. The revised control system must factor in the additional requirements of the HVAC system, while still optimizing performance of the M1 ventilation system and the M1’s optical behavior. An industry-standard HVAC communication and networking protocol, BACnet (Building Automation and Control network), has been adopted. Integration of the BACnet protocol into the existing software framework at the MMT is discussed. Performance of the existing automated system is evaluated and a preliminary upgraded automated control system is presented. Finally, user interfaces to the new HVAC system are discussed.
Details of the software framework for the upcoming in-situ re-aluminization of the 6.5m MMT Observatory (MMTO) primary mirror are presented. This framework includes: 1) a centralized key-value store and data structure server for data exchange between software modules, 2) a newly developed hardware-software interface for faster data sampling and better hardware control, 3) automated control algorithms that are based upon empirical testing, modeling, and simulation of the aluminization process, 4) re-engineered graphical user interfaces (GUI’s) that use state-of-the-art web technologies, and 5) redundant relational databases for data logging. Redesign of the software framework has several objectives: 1) automated process control to provide more consistent and uniform mirror coatings, 2) optional manual control of the aluminization process, 3) modular design to allow flexibility in process control and software implementation, 4) faster data sampling and logging rates to better characterize the approximately 100-second aluminization event, and 5) synchronized “real-time” web application GUI’s to provide all users with exactly the same data. The framework has been implemented as four modules interconnected by a data store/server. The four modules are integrated into two Linux system services that start automatically at boot-time and remain running at all times. Performance of the software framework is assessed through extensive testing within 2.0 meter and smaller coating chambers at the Sunnyside Test Facility. The redesigned software framework helps ensure that a better performing and longer lasting coating will be achieved during the re-aluminization of the MMTO primary mirror.
Over the past few years, the MMT Observatory has developed a number of web browser front ends for operation
interfaces and staff access to internal databases. Among these is a facility for viewed reduced tracking logs in both time
series and FFTs for convenient examination of tracking performance. Part of the back-end software also keeps the
tracking data in a searchable database, allowing data over long periods of time to be collected and analyzed to look for
trends, the influence of environmental factors on tracking, and help detect tracking degradation in a timely manner.
An integrated scheduling and program management system is being developed for the MMT Observatory (MMTO),
Arizona, USA. A systems engineering approach is used to combine existing and new relational databases, spreadsheets,
file storage systems, and web-based user interfaces into a single unified system. An overview of software design, data
management, user interfaces, and techniques for performance assessment is presented. Goals of this system include
streamlined data management and an optimized user experience. The MMTO has over a dozen different telescope
configurations, including three secondary mirrors and a wide range of observing instruments. Scheduling is complex for
the varying telescope configurations, limited available observing time, and appropriate astronomic conditions (e.g., lunar
phase) for each science project. Scheduled telescope configurations can be used to perform safety checks of actual
configuration during telescope operations. Programmatic information is automatically input into nightly telescope
operator (TO) logs by the system. The TO's provide additional information into the system on telescope usage,
observing conditions (e.g., weather conditions), and observatory closure (e.g., from instrument malfunction or inclement
weather). All of this information is synthesized to assess telescope and observatory performance. Web interfaces to the
system can be used by observers to submit information, such as travel plans, instrumentation requirements, and
observing catalogs. A service request (SR) (i.e., trouble report) system has also been developed for tracking operational
issues. The specific needs of the MMTO have been met through in-house software development of this integrated
scheduling and program management system.
An object-oriented software approach to acquisition and logging of telemetry data has been implemented at the MMT
Observatory (MMTO). This approach includes: 1) a uniform interface to RS-232 serial and TCP/UDP network-enabled
hardware devices, 2) a multiplexed socket server able to handle multiple simultaneous connections, 3) a simple ASCII
network protocol, 4) standardized relational and round-robin database logging, 5) consistent parameter naming
conventions, 6) automatic data validation, 7) centralized configuration files, and 8) unified process control. Over 25
miniservers, each of which corresponds to a single hardware device, implement the hardware-specific protocol for
communication with that hardware device. The miniserver collects data from the device and allows network access to
the dataset for that device via a uniform ASCII protocol. Each miniserver also periodically logs data to relational and,
optionally, round-robin databases. Over 29 gigabytes of logged telemetry data, representing over 1500 distinct
parameters and 120,000,000 MySQL records, are currently available for the past 4-5 years through this software
framework. Essentially any scripting language can be used to access the ASCII-based network interface and MySQL
relational databases. This object-oriented approach to telemetry provides a framework into which new hardware devices
can easily be added and leverages existing data acquisition, analysis, and visualization tools.
In using common HTML/Ajax approaches for web-based data presentation and telescope control user interfaces at the
MMT Observatory (MMTO), we rapidly were confronted with web browser performance issues. Much of the
operational data at the MMTO is highly dynamic and is constantly changing during normal operations. Status of
telescope subsystems must be displayed with minimal latency to telescope operators and other users. A major
motivation of migrating toward web-based applications at the MMTO is to provide easy access to current and past
observatory subsystem data for a wide variety of users on their favorite operating system through a familiar interface,
their web browser. Performance issues, especially for user interfaces that control telescope subsystems, led to
investigations of more efficient use of HTML/Ajax and web server technologies as well as other web-based
technologies, such as Java and Flash/Flex. The results presented here focus on techniques for optimizing HTML/Ajax
web applications with near real-time data display. This study indicates that direct modification of the contents or
"nodeValue" attribute of text nodes is the most efficient method of updating data values displayed on a web page. Other
optimization techniques are discussed for web-based applications that display highly dynamic data.