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Receiver Range Control Electronics Sigma Space Corp. Concept 7x7 Detector Array 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Detector Anode Array Limit of Field of View Perimeter pixel used for CLT Corner pixels not used Noise Satellite Returns (collected over a frame) Pixelated Detector / Event Timer Acquisition And Tracking FOVs Operational Status Commands Receiver Data From Detector Array Range Gate Optical Bench Optical Control Interface Device Control Beam Monitoring Operational Status Subsystem Configuration Operational Status Laser Weather/Sky Weather, Visibility, and Sky Clarity Data Operational Status Abstract: The NASA Space Geodesy Satellite Laser Ranging (SGSLR) system design plans for fully automated SLR operations. Automating the systems will require a phased approach as NASA develops, builds and deploys the first three SGSLR systems for the next generation NASA Network. The SGSLR Computer and Software (C&S) subsystem will control, command, or monitor all aspects of the system during every mode of operation, and will be capable of post processing and delivering all science and housekeeping data to the NASA Integrated Geodetic Site Operations Center (IGSOC). The C&S subsystem will provide SGSLR the capability for local and remote operations, as well as the capability to operate 24 hours a day, 7 days a week with no human intervention (except for periodic routine maintenance and occasional repairs). This poster will describe the computer and software subsystem design and interface to the SGSLR subsystems providing the framework for the final phase of SGSLR automation development. SGSLR AUTOMATION AND THE COMPUTER AND SOFTWARE SUBSYSTEM DESIGN J. Horvath 1 , J. Cheek 3 , A. Mann 1 , C. Clarke 1 , M. Heinick 1 , R. Ricklefs 4 , J. McGarry 2 , H. Donovan 1 , F. Hall 1 , E. Hoffman 2 , A. Nelson 1 , S. Wetzel 1 7515 Mission Drive Lanham MD 20706 20 th International Laser Ranging Workshop Potsdam, Germany October 9-14, 2016 1 Honeywell Technology Solutions, Inc., Lanham, MD 20706 USA | 2 NASA Goddard Space Flight Center, Greenbelt, MD 3 SigmaSpace Corp., Greenbelt, MD | 4 Cybioms Corp., Rockville, MD Telescope and Gimbal Control Operational Status Equipment Sensors GTA Temperature Accelerometers Shelter and Dome Dome Control System Environment System Power Station Security Operational Status P r o c e s s e d S c i e n c e D a t a , E n g in e e r i n g D a t a , M o n i t o r i n g , G e n e r a l A l e r t s , S t a t u s R e p o r t s S y s t e m S c h e d u l e / C o mm a n d s CDDIS/ EDC Eme rg e n c y Al e r t s Sys tem S t atus Repo rts Emergency Stop Controller C&S continuously monitors weather and sky sensors for both system protection and tracking efficiency. The software will monitor for precipitation and out of bounds weather (MET and wind) conditions, automatically closing the dome shutter so that system protection is ensured. The software will also monitor sky conditions for satellite acquisition. All data will be transferred to IGSOC for trending and status reporting. C&S configures and continuously monitors laser energy, transferring current status information to the IGSOC. C&S controls the Gimbal and Telescope (GTA) by sending position commands for all operational modes: satellite tracking, ground calibration, star calibration, and static pointing. Pointing is continuously optimized using information from the pixelated detector to center the returns in the receiver FOV. GTA sends back pointing and status feedback to the C&S for both real- time monitoring and housekeeping data transfer for monitoring at the IGSOC. Laser Safety Subsystem controls all laser safety functions and will automatically insert beam blocks on the optical bench and inhibit the laser from firing when an aircraft is within the FOV of the laser. C&S makes requests to resume laser operations, however the laser safety will only allow operations when the aircraft has left the aircraft detection FOV. Aircraft detect and subsystem status data will be collected and transferred to the IGSOC for availability to the sustaining engineering team. Dome slaved to gimbal during most operational modes Subsystem Control / Configuration Device Control / Configuration Real-Time Functions Operator Decisions Pointing Angle Generation Range Gate Delay Generation Pulse Repetition Frequency Satellite Acquisition And Signal Identification Data Collection From Receiver Time/Angle Bias Control Time-Tagging Satellite Interleaving Subsystem Monitoring Restricted Tracking IGSOC Command Execution Data Post Processing & Data Delivery C&S sends range gate delays for range gate generation, laser pulse fire rates for collision avoidance, and acquisition & tracking FOV to the receiver control electronics. Receiver subsystem collects the data and sends all fire and receive data from all 49 channels of the pixelated detector for signal identification, closed loop tracking, data time-tagging, range calculation and normal point generation. C&S continuously biases pointing angles to move returns to the center of pixelated detector. C&S configures, controls and monitors devices on optical bench during operations including: star camera and filter for star calibration, Risley prisms for point ahead capability, beam expander for beam divergence; day/night filter, iris, ND wheels for receive attenuation, and acquisition FOV for satellite acquisition. Timing and Frequency Subsystem Configuration Operational Status Timing Monitoring IGSOC (Conceptual Image) Sustaining Engineering Laser BX 56C-30-1-8 Receiver Risley Prisms Beam Expander Star Camera Star Camera Day/Night Filter ND Wheels Day/Night Filter FOV IRIS Processed Science Data C&S transfers all science data products, system and subsystem monitoring data, engineering data, general alerts and status reports to the IGSOC. Any emergency alerts are sent directly to Sustaining Engineering personnel for immediate response. IGSOC provides SGSLR monitoring capability, automatic alerting, and long-term trending to NASA remote operators and sustaining engineering teams. The IGSOC also performs all NASA Operations Center functions as well as system commanding. C&S configures and monitors system power, configures and monitors environmental conditions inside shelter, monitors fire/water sensors, and provides emergency shutdown capability. C&S monitors the dome environment and dome position and will control position during periods of automated survey monitoring sessions and sustaining engineering. When the outside weather reaches out of bound conditions the C&S will close the dome shutter to protect the equipment inside the dome. C&S provides network access to both internal and external security cameras for monitoring from the IGSOC and real-time troubleshooting by the sustaining engineering team. Telescope and Gimbal Image courtesy of Cobham PLC Laser Image courtesy of Photonics Industries TBAD Aircraft Avoidance System* Laser Hazard Reduction System** Laser Safety Sensor Detection Log Operational Status * Transponder-Based Aircraft Detector (TBAD) image courtesy of Aircraft Avoid.com Multi Frequency GPS Time and Frequency Source Single Frequency GPS Time and Frequency provides accurate date/time (USNO) timing signals to most SGSLR subsystems including the C&S. C&S provides configuration at startup and continuous real-time monitoring of system timing using the redundant timing sources. Monitoring data is transferred to the IGSOC for long-term trending and analysis. * *Radar image courtesy of Honeywell Technology Solutions Inc. Sigma Space Corp. Concept Anemometer Temperature, Pressure and Humidity Sensor Horizontal Visibility & Precipitation Sensor All-Sky Camera Safety Sensors and Signs Interlocks Emergency Stop AUTOMATION
