Space Technology 7 (ST-7) Concept Study

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Space Technology 7 (ST-7)Concept Study
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ST-7 Concept Study

• Objectives
• Demonstrate model-based autonomy on real-world
  missions.
• Demonstrate additional model-based capabilities
  not deployed onDS-1
• Model-based Planning
• Model-based Sequencing
• Multi-step Reconfigurations
• Approach Integrate Kirk and Titan technology
  into ST-7
• Space Technology 7 proposed NASA New Millennium
  mission to validate s/w h/w technologies for
  autonomous operation.

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New Millennium ST-7Autonomy Mission Concept

• Autonomy one of 4 competing technologies.
• 6-month concept definition phase ended January
  2002.
• Autonomy-ready s/c design based on primarily
  off-the-shelf components.
• Mission design highlighting
• Onboard execution of activities normally
  commanded from ground
• Science-driven execution
• Software testbed demonstration.

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Software Demonstrations of ST-7 Scenarios

• Demonstrate Titan and Kirk in the context of a
  simulated mission scenario, with realistic h/w
  models.
• Kirk System-level
• Science Observation and Downlink Scenario
• Model-based Planning
• Planner/Executive Interaction (Plan Running)
• Titan Engineering-level
• Downlink Data Block Activity
• Model-based Sequencing
• Mode Estimation and Mode Reconfiguration

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Science Observation and Downlink Diagram
KIRK Features
STARTPerform observation A?
Reorient s/c to B
no
yes
Perform obs A,prepare data
Perform obs B,prepare data
Is s/c pos B?
Use Omni A?
no
No, use omni B
yes
Reorient s/c to A
Reorient s/c to B
Is s/c pos A?
no
yes
yes
Replan
Downlink data block
success
END
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Software Demonstrations of ST-7 Scenarios

• Demonstrate Titan and Kirk in the context of a
  simulated mission scenario, with realistic h/w
  models.
• Kirk System-level
• Science Observation and Downlink Scenario
• Model-based Planning
• Planner/Executive Interaction (Plan Running)
• Titan Engineering-level
• Downlink Data Block Activity
• Model-based Sequencing
• Mode Estimation and Mode Reconfiguration

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Downlink Data Block Activity

• Objective downlink a block of data from onboard
  storage to a specified ground station

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Downlink Data Block Component Models
start-streaming
STREAMING- RT-TELEM
IDLE
go-idle
start- downlinking
stop- downlinking
go-idle
UNKNOWN
DOWNLINKING-DATA
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Downlink Data Block Component Models
STUCK-AT-A
ENABLE-OMNIA
STUCK-AT-B
selectB
selectA
ENABLE-OMNIB
UNKNOWN
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Downlink Data Block Sequence - Initial State

• omniA in view of ground station
• no ground command received
• omniA in nominal mode (remains so throughout)
• omniB in nominal mode (remains so throughout)
• transmitter in idle mode
• switch set to enable omniB

enable-omniB
idle
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Downlink Data Block Sequence

• Set switch to enable appropriate omnidirectional
  antenna for downlink of streaming real-time
  telemetry (based on omni-in-view info from ACS).

set to mode enable-omniA
idle
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Downlink Data Block Sequence

• Set switch to enable appropriate omnidirectional
  antenna for downlink of streaming real-time
  telemetry (based on omni-in-view info from ACS).
• If switch gets stuck in wrong position, fail
  DownlinkDataBlock activity.

fail when mode stuck-at-B
idle
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Downlink Data Block Sequence

• Set switch to enable appropriate omnidirectional
  antenna for downlink of streaming real-time
  telemetry (based on omni-in-view info from ACS).
• If switch gets stuck in wrong position, fail
  DownlinkDataBlock activity.
• Otherwise, set transmitter to start streaming
  real-time telemetry so that ground can establish
  communication link.

set to mode streaming-rt-telem
enable-omniA
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Downlink Data Block Sequence

• Set switch to enable appropriate omnidirectional
  antenna for downlink of streaming real-time
  telemetry (based on omni-in-view info from ACS).
• If switch gets stuck in wrong position, fail
  DownlinkDataBlock activity.
• Otherwise, set transmitter to start streaming
  real-time telemetry so that ground can establish
  communication link.

streaming-rt-telem
enable-omniA
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Downlink Data Block Sequence

• Set switch to enable appropriate omnidirectional
  antenna for downlink of streaming real-time
  telemetry (based on omni-in-view info from ACS).
• If switch gets stuck in wrong position, fail
  DownlinkDataBlock activity.
• Otherwise, set transmitter to start streaming
  real-time telemetry so that ground can establish
  communication link.
• When start-playback command received from ground,
  start downlinking data from onboard storage.

set to mode downlinking-data
enable-omniA
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Downlink Data Block Sequence

• Set switch to enable appropriate omnidirectional
  antenna for downlink of streaming real-time
  telemetry (based on omni-in-view info from ACS).
• If switch gets stuck in wrong position, fail
  DownlinkDataBlock activity.
• Otherwise, set transmitter to start streaming
  real-time telemetry so that ground can establish
  communication link.
• When start-playback command received from ground,
  start downlinking data from onboard storage.

downlinking-data
enable-omniA
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Downlink Data Block Sequence

• Set switch to enable appropriate omnidirectional
  antenna for downlink of streaming real-time
  telemetry (based on omni-in-view info from ACS).
• If switch gets stuck in wrong position, fail
  DownlinkDataBlock activity.
• Otherwise, set transmitter to start streaming
  real-time telemetry so that ground can establish
  communication link.
• When start-playback command received from ground,
  start downlinking data from onboard storage.
• When downlink finished, idle transmitter and
  report success of DownlinkDataBlock activity.

set to mode idle
enable-omniA
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Titan Demonstration
Control Program
Plant Models
HELIOS Plant Model Visualization
Titan
Java Display
C Engine
Activity from Plan Runner
Export

• Mode estimates
• Configuration goals
• Issued commands