sgslr automation and the computer and software … · resume laser operations, however the laser...

Receiver

Range Control Electronics

Sigma Space Corp. Concept7x7 Detector Array

1 2 3 4 5 6 7

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2

3

4

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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 ControlBeam Monitoring

Operational Status

Subsystem ConfigurationOperational Status

Laser

Weather/SkyWeather, 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 DESIGNJ. Horvath1, J. Cheek3, A. Mann1, C. Clarke1, M. Heinick1, R. Ricklefs4,

J. McGarry2, H. Donovan1, F. Hall1, E. Hoffman2, A. Nelson1, S. Wetzel1

7515 Mission DriveLanham MD 20706

20th International Laser Ranging Workshop Potsdam, GermanyOctober 9-14, 2016

1Honeywell Technology Solutions, Inc., Lanham, MD 20706 USA | 2NASA Goddard Space Flight Center, Greenbelt, MD 3SigmaSpace Corp., Greenbelt, MD | 4 Cybioms Corp., Rockville, MD

Telescope and GimbalControlOperational StatusEquipment Sensors

GTA TemperatureAccelerometers

Shelter and DomeDome Control

System EnvironmentSystem Power

Station SecurityOperational Status

Pro

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Eng

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Dat

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Mon

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Gen

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Sta

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Rep

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Syst

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/ Com

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CDDIS/ EDC

Emer

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System Status Reports

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 / ConfigurationDevice Control / Configuration Real-Time Functions

Operator DecisionsPointing Angle GenerationRange Gate Delay GenerationPulse Repetition FrequencySatellite Acquisition And Signal IdentificationData Collection From ReceiverTime/Angle Bias ControlTime-TaggingSatellite InterleavingSubsystem Monitoring

Restricted TrackingIGSOC Command ExecutionData 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 FrequencySubsystem Configuration

Operational StatusTiming Monitoring

IGSOC(Conceptual Image)

Sustaining Engineering

Laser

BX 56C-30-1-8

Receiver

Risley Prisms

Beam ExpanderStar Camera

Star CameraDay/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 GimbalImage courtesy of Cobham PLC

LaserImage courtesy of

Photonics Industries

TBAD Aircraft Avoidance System*

Laser Hazard Reduction System**

Laser SafetySensor Detection Log

Operational Status

* Transponder-Based Aircraft Detector (TBAD) image courtesy

of Aircraft Avoid.com

Multi Frequency GPS

Time and FrequencySource

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