GLAST LAT Project
Gamma-ray Large
Area Space
Telescope
ISOC CDR, 4 August 2004
GLAST Large Area Telescope:
Instrument Science Operations Center
CDR
Section 2
Requirements
Jim Martin
SLAC
jfm@slac.stanford.edu
650-926-4895
Document: LAT-PR-04500
Section 2
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GLAST LAT Project
ISOC CDR, 4 August 2004
LAT Specification Tree
Mission System
Specification
433-SPEC-0001
Operations Data
Products (ICD)
Mission
Science
Requirements
Document
433-SRD-0001
LAT
LEVEL
Interface
Rqmts
Science
Rqmts
LAT-SC Interface
Requirements
Document
433-IRD-0001
Mission
Rqmts
Science Data
Products (ICD)
Ground System
Requirement
Documents
433-RQMT-0006
I
Interface
Rqmts
Mechanical
Subsystem
Specification
LAT-SS-00115
TCS Performance
Specification
LAT-SS-00715
LAT ISOC
Performance
Specification
LAT-SS-00015
LAT-SC Interface
Control
Documents
Trigger & Dataflow
Subsystem
Specification
LAT-SS-00019
TKR Subsystem
Specification
LAT-SS-00017
Power
Subsystem
Specification
LAT-SS-00136
ACD Subsystem
Specification
LAT-SS-00016
SAS
Subsystem
Specification
LAT-SS-00020
LAT
LAT
Environmental
Specification
LAT-SS-00778
LAT Subsystem
LAT Performance
Specification
LAT-SS-00010
ISOC
Subsystem
Specification
LAT-SS-00021
CAL Subsystem
Specification
LAT-SS-00018
55 Level II Requirements
379 Level III Requirements
Document: LAT-PR-04500
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II
III
GLAST LAT Project
ISOC CDR, 4 August 2004
Level II Requirements
Level II
Science Operations
6
Instrument Operations
17
Analysis Software and Data Processing
19
Interfaces
3
Data Standards and Data Format Standards
7
Availability and Reliability
1
Automation
1
Security
1
TOTAL
55
Document: LAT-PR-04500
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GLAST LAT Project
ISOC CDR, 4 August 2004
Driving Requirements
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4.3.7 - LAT Instrument Commanding
– Generate LAT instrument commands and identify procedures to direct the safe
upload of the commands.
4.3.9 - LAT Instrument Flight Software
– Maintain, update, and validate the operation and performance of the LAT flight
software.
4.3.10 - LAT Instrument Simulator
– Maintain an instrument simulator for validating and verifying changes to flight
software and command procedures, and also for use in anomaly resolution.
4.4.1 - Level 0 Data Processing
– Receive Level 0 data from the MOC post-pass and process the data into Level 1
event data within 24 hours of receipt from the MOC.
4.4.2 - Real-time Housekeeping Data
– Autonomously receive real-time housekeeping data in near real-time from the
MOC and process the data for diagnostic use.
4.4.6 - Instrument Response Simulation
– Develop and maintain software to simulate the detailed response of the LAT to
charged particles and gamma rays.
4.4.5 - Event Reconstruction and Classification
– Develop algorithms to interpret the subsystem responses, apply calibration
constants, and to find and identify incident photons.
Document: LAT-PR-04500
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level II – LAT-SS-00015
Science Operations
#
Title
Summary
Verification
4.2.1
LAT Instrument
Calibration
Produce, monitor and update calibration
constants for the instrument
T
4.2.2
Instrument Response
Functions (IRFs)
Generate IRFs needed for science analysis
T
4.2.3
LAT Instrument
Performance
Assess the LAT instrument performance and
compare actual performance against
predicted performance.
T
4.2.4
LAT Instrument
Optimization
Optimize the LAT instrument in response to
in-flight changes in hardware as described
in the ISOC Operations Plan, LAT-SS01378.
T
4.2.5
Performance Records
Archive data on the performance and
calibration of the LAT instrument.
D
4.2.6
Retrieval of Archived
Records
Retrieve archived performance and
calibration data at a rate of at least 1 GB
in 60 minutes.
T
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level II – LAT-SS-00015
Instrument Operations – 1/3
#
Title
Summary
Verification
4.3.1
Health and Safety
Monitoring
Monitor the health and safety of the
instrument.
T
4.3.2
Housekeeping Data
Process and analyze LAT housekeeping
data.
T
4.3.3
Operating Limits
Define the operating limits for the LAT
instrument.
T
4.3.4
Anomaly Response
Monitor for and respond to anomalous
configurations or states.
T
4.3.5
Operations Records
Maintain records of the operation and health
of the LAT instrument.
D
4.3.6
LAT Instrument
Configuration
Maintain the status of on-board operating
parameters and control the configuration
of the LAT instrument.
T
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level II – LAT-SS-00015
Instrument Operations – 2/3
Req't #
Title
Summary
Verif. Method
4.3.7
LAT Instrument
Commanding
Generate LAT instrument commands and
identify procedures to direct the safe
upload of the commands.
T
4.3.8
Telemetry and
Command
Databases
Develop and maintain command and
telemetry databases used for
generating LAT instrument commands
and analyzing the health, performance,
and operation of the LAT instrument.
T
4.3.9
LAT Instrument
Flight Software
Maintain, update, and validate the
operation and performance of the LAT
flight software.
T
4.3.10
LAT Instrument
Simulator
Maintain an instrument simulator for
validating and verifying changes to
flight software and command
procedures, and also for use in
anomaly resolution.
D
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level II – LAT-SS-00015
Instrument Operations – 3/3
Req't #
Title
Summary
Verif. Method
4.3.11
Mission Operations
Provide mission operation support for the LAT
instrument.
4.3.11.1
Command Uplink
Provide instrument command uploads to the
GSSC for on-orbit instrument operations
and to the MOC during pre-launch test and
early orbit periods.
T
4.3.11.2
Command Scheduling
Coordinate LAT commanding schedules with the
GSSC.
T
4.3.11.3
Anomalies
Coordinate the resolution of LAT instrument
anomalies with the MOC.
D
4.3.11.4
Pre-Launch Activities
Provide personnel and facilities to support prelaunch interface and system test activities.
D
4.3.11.5
On-orbit Checkout
Perform initial tests and analysis of LAT
instrument operation and performance
during an on-orbit checkout period of 60
days.
T
4.3.11.6
Operational Period
Support an on-orbit operational lifetime of a
minimum of 5 years following an initial
period of on-orbit checkout.
T
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level II – LAT-SS-00015
Analysis Software and Data Processing – 1/3
Req't #
Title
Summary
Verif. Method
4.4.1
Level 0 Data Processing
Receive Level 0 data from the MOC post-pass
and process the data into Level 1 event data
within 24 hours of receipt from the MOC.
T
4.4.1.1
Data Quality
Evaluate the quality of the Level 0 data and
determine if retransmission of the data from
the MOC is required.
T
4.4.1.2
Retransmitted Level 0
Data
Process retransmitted Level 0 data within 24
hours of receipt from the MOC.
T
4.4.1.3
Duplicate Level 0 Data
Process Level 0 data received from the MOC
that duplicates or overlaps portions of
previously received Level 0 data.
T
4.4.2
Real-time Housekeeping
Data
Autonomously receive real-time housekeeping
data in near real-time from the MOC and
process the data for diagnostic use.
T
4.4.3
Unfiltered Data
Process unfiltered data generated by the
instrument hardware trigger.
T
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level II – LAT-SS-00015
Analysis Software and Data Processing – 2/3
Req't #
Title
Summary
Verif. Method
4.4.4
Level 1 Data Processing
Maintain a processing pipeline for event
reconstruction and classification.
D
4.4.5
Event Reconstruction and
Classification
Develop algorithms to interpret the subsystem
responses, apply calibration constants, and
to find and identify incident photons.
T
4.4.6
Instrument Response
Simulation
Develop and maintain software to simulate the
detailed response of the LAT to charged
particles and gamma rays.
T
4.4.7
Level 2 Data Processing
Maintain a processing pipeline for Level 2
analysis tasks that can be automated, such
as searching for transient sources,
monitoring the in-flight IRFs, and refining
information about alerts for transient
sources generated by the instrument.
D
4.4.8
Science Analysis Tools
Develop and provide to the GSSC and LAT
team science analysis tools to analyze
Level 1 data.
D
4.4.9
Science Data Format
Provide Level 1 and Level 2 data to GSSC and
the LAT team in an agreed upon format.
T
Document: LAT-PR-04500
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level II – LAT-SS-00015
Analysis Software and Data Processing – 3/3
Req't #
Title
Summary
Verif. Method
4.4.10
LAT Mirror Sites
Provide data to any associated international
or domestic mirror sites provided as part
of the LAT team efforts.
D
4.4.11
Data Storage
Archive all raw data and processed data
products for the duration of the mission.
D
4.4.12
Pre-launch Test and
Calibration Data
Archive LAT test and calibration data
obtained during pre-launch testing.
T
4.4.13
Alerts
Receive and process LAT alert messages.
T
4.4.13.1 Validating Alerts
Use LAT science data to validate and refine
the scientific alert information.
T
4.4.13.2 Submitting Alerts to
GCN
Transmit refined scientific alerts to the
Gamma Ray Burst Coordinates Network
(GCN).
T
4.4.13.3 Instrument Alerts
Receive, process, and respond to LAT
instrument alert messages.
T
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level II – LAT-SS-00015
Interfaces
Req't
#
Title
Summary
Verif. Method
4.5.1
GSSC, LAT Team, and
LAT Mirror Site
Interface for Science
Data Products
Interface with the GSSC, LAT team, and
LAT mirror sites to provide and
receive science data products.
D
4.5.2
GSSC Interface for
Operational Data
Products
Interface with the GSSC to provide and
receive operational data products,
including instrument commands.
D
4.5.3
MOC Interface for
Operational Data
Products
Interface with the MOC to provide and
receive operational data products.
D
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level II – LAT-SS-00015
Data and Data Format Standards
Req't #
Title
Summary
Verif. Method
4.6.1
Coordinate System
Use the J2000 inertial coordinate system as the
basis for identifying and reporting celestial
objects and of communicating pointing
directions.
T
4.6.2
Use of Metric Units
Per NASA policy directive NPD 8010.2B, use
metric in all data processing and design
calculations in the LAT ISOC.
T
4.6.3
Time Base
Use UTC as the time base for operations
T
4.7.1
Communications Format and
Protocol
Employ the standard communications format
and protocol as recommended by CCSDS
for telemetry and telecommands.
T
4.7.2
Variable Length Packets
Accept and accommodate variable CCSDS
length packets for science, housekeeping,
and alert data.
T
4.7.3
Software Upload Formats
Format software uploads in blocks as specified
by the MOC.
T
4.7.4
Science Analysis Tools
Formats
Adhere to standards that ensure software
portability, independence of vendor and
compatibility with existing multi-mission
high energy astrophysics tools.
D
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level II – LAT-SS-00015
Availability, Reliability, Automation, Security
Req't #
Title
Summary
Verif. Method
4.8
Availability and
Reliability
Maintain ISOC facilities for the entire
mission lifetime with no loss in ISOC
capability or performance.
A
4.9
Automation
Accept autonomous data transfers from
the MOC.
T
4.10
Security
Connect to the other operations and
support centers by an intranet of
wide area networks that is closed to,
or protected from, public users of the
external internet per NASA NPD
2810.1.
T
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level III – LAT-SS-00021
# of Level III
3.1
Configuration and Architecture
3.1.1
Interface
3.1.2
Facilities
3.1.3
Redundancy
3.1.4
Security
3.1.5
Database
3.1.6
Website
3.1.7
Documentation
60
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11
6
6
5
6
4
3.2
Mission Planning & Scheduling
3.2.1
Flight Dynamics
3.2.2
TDRSS scheduling
3.2.3
Target of Opportunity
3.2.4
Stored Command Load Generation
62
3
2
8
49
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level III – LAT-SS-00021
Continued – 2/3
# of Level III
3.3
3.3.1
3.3.2
3.3.3
3.3.4
3.3.5
3.3.6
Telemetry, Command & Data Processing
Telemetry Processing
Data Processing
Data Archiving
Alert Telemetry Monitoring
User Interface Language
Commanding
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1
22
4
Section 2
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GLAST LAT Project
ISOC CDR, 4 August 2004
REQUIREMENTS – Level III – LAT-SS-00021
Continued – 3/3
# of Level III
3.4
3.4.1
3.4.2
3.4.3
3.4.4
3.4.5
3.4.6
3.4.7
3.4.8
3.4.9
3.4.10
3.4.11
Monitoring and Analysis
Ground System Monitoring
Display Pages
Sequential Prints
Event Messages
Memory Mapping & Maintenance
Limit Monitoring
Configuration Monitoring
Trending & Analysis
Anomaly Tracking & Notification
Timeline Monitoring
Calibration & Performance
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4
38
15
13
7
14
15
32
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3
6
Section 2
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GLAST LAT Project
ISOC CDR, 4 August 2004
Summary
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Requirements are in the signature cycle
– Review and update as needed after GSDR
Development approach tailored to Level III
Ready to develop
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