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Load Review SCS-155 Deadman and HETG Checks

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@Gregg140 Gregg140 released this 29 Mar 20:58
· 75 commits to master since this release
1.2.0
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Change Description

This update to the ACIS Ops Load Review software provides checks for
the two Priority 2 guidelines as described in:

https://occweb.cfa.harvard.edu/twiki/bin/view/Constraints/MPGuidelines/Release/GuidelineRadiationSafingWithoutHRC

These are:

"When HRC data is not used for onboard radiation monitoring and safing, ensure the following:

  1. HETG is inserted by rad entry, either during the same maneuver used to safe the SIM or prior,
    and kept in until at least the start of the maneuver to the first target exiting the rad
    zone Priority 2.

  2. Ensure the following is commanded for every rad entry Priority 2:

    Time Event
    Rad Entry Minus 48h Activate SCS-155 containing; A_NSM_XXHR.RTS timer = 48h, 10m
    Rad Entry Nominal SI Safing
    Rad Entry + 5m Disable SCS-155"

The second guideline is referred to as the SCS-155 Deadman check, or
Deadman Check in this document.

For item 1, the update includes a new program: HETG_Check.py, which
checks the status of the HETG as compared to the perigee passages and
will flag a load which does not have the HETG in for the perigee passage.

For item 2, the update includes an new program: Deadman_Check.py which
will determine if the SCS-155 enable, activate and disable commands
appear in the load, and checks the timing of those commands as
compared to the guideline. SCS-155 contain the deadman timer and code
which will execute at deadman timer timeout and which protects ACIS.

The load review program itself, lr, was modified to execute the two
programs. In addition, to handle the circumstance where the SCS-155
enable and activate commands appear at the end of the Review load, but
the subsequent Radzone entry does not appear in the load, lr was
modified to extract the Orbital Events file (DO*.orp) from the load
week tarball. Utility programs were written to extract the information
from the DO*.orp file for use by Deadman_check.py as well as other
convenience programs.

Output from the two programs appears on the screen while lr is
running, and also appears in the log file created when LR is run, and
stored in the OFLS directory for that load week.

Files Changed or added:

The changes can be seen here:

#33

Testing:

The changes were tested by running these regression test loads:

FEB2122
FEB2822
MAR0722
MAR1122
MAR1422
MAR2122
MAR2822
JAN1022 - prior to the guideline being implemented, tests failure modes.

TEST_MAR2122 - MAR2122 load hand modified to test placement of the
SCS-155 disable command after the deadman timeout

These tests included all examples of load where the guidelines were
implemented which included Normal and TOO load types.

All tests passed.

Interface impacts

None

Review

ACIS Ops

Deployment Plan

Will be deployed after FSDS approval.

Assets 2
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