Hi all,

I have looked at the orbit 0525 ATS files, IBEX_2021_111_o0525a_BUS_v001.scr, IBEX_2021_111_o0525a_INST_v001.scr and I approve.

The constraint violations in IBEX_2021_111_o0525a_BUS_v001.ccvr and IBEX_2021_111_o0525a_INST_v001.ccvr

are from the removal of the ACT_SetSpinPulseProtectEnable Enable commands. The violations are acceptable.

The PL commands in IBEX_2021_111_o0525a_INST_v001.scr match those in the STF, IBEX_2021_111_o0525a_v002.stf

Ascending and descending command sequences are consistent with each other, 15 Re ascending, the apogee maneuver time and 15 Re descending as determined from the OEF, IBEX_2021_111_o0525a_BUS_v001.oef and as verified with ibex_orbit.

There are two star tracker outages. The first one is for 2 days after apogee and lasts for 27.15 hours. The second is 8.45 hours long and ends 6 hours before perigee.

The ground station command sequences are correct and the timing and bit rates match those in the contacts file, IBEX_Orbit525_Contacts.txt for all contacts (3).

Battery Balancing is 90.0 minutes long, 7.8 hours away from PL descending, and 3.12 hours away from the maneuver.

The Inertial maneuver at perigee of orbit 0524 left us pointing in safe directions for the orbit 0525 arc A ascending and descending sequences:

ibex_rotate -o -u 0.874234,0.448948,0.184826 -w ibex-sun -t 2021/04:21:19:01:26

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.874234,+0.448948,+0.184826

which is R.A. +27.182 Decl. +10.651

missing R.A. +29.417 Decl. +12.002 (ibex-sun)

error is R.A. +2.235 Decl. +1.351

for a total 2.575 deg

ibex_rotate -o -u 0.874234,0.448948,0.184826 -w ibex-sun -t 2021/04:25:14:10:39

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.874234,+0.448948,+0.184826

which is R.A. +27.182 Decl. +10.651

missing R.A. +33.083 Decl. +13.317 (ibex-sun)

error is R.A. +5.901 Decl. +2.666

for a total 6.358 deg

The inertial precession maneuver at apogee leaves us pointing in safe directions at the time of the maneuver and for arc B ascending and descending sequences:

ibex_rotate -o -u 0.834248,0.509807,0.210062 -w ibex-sun -t 2021/04:25:15:53:47

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.834248,+0.509807,+0.210062

which is R.A. +31.429 Decl. +12.126

missing R.A. +33.152 Decl. +13.342 (ibex-sun)

error is R.A. +1.723 Decl. +1.216

for a total 2.074 deg

ibex_rotate -o -u 0.834248,0.509807,0.210062 -w ibex-sun -t 2021/04:25:17:28:53

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.834248,+0.509807,+0.210062

which is R.A. +31.429 Decl. +12.126

missing R.A. +33.215 Decl. +13.365 (ibex-sun)

error is R.A. +1.786 Decl. +1.239

for a total 2.137 deg

ibex_rotate -o -u 0.834248,0.509807,0.210062 -w ibex-sun -t 2021/04:30:07:10:16

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.834248,+0.509807,+0.210062

which is R.A. +31.429 Decl. +12.126

missing R.A. +37.462 Decl. +14.782 (ibex-sun)

error is R.A. +6.033 Decl. +2.656

for a total 6.440 deg

The inertial precession maneuver at perigee leaves us pointing in safe directions at the time of the maneuver and at orbit 0526 apogee:

ibex_rotate -o -u 0.788422,0.567896,0.236397 -w ibex-sun -t 2021/04:30:11:52:36

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.788423,+0.567896,+0.236397

which is R.A. +35.765 Decl. +13.674

missing R.A. +37.640 Decl. +14.831 (ibex-sun)

error is R.A. +1.875 Decl. +1.157

for a total 2.154 deg

ibex_rotate -o -u 0.788422,0.567896,0.236397 -w ibex-sun -t 2021-05-05T05:39:32

Quaternion +0.000000,+0.000000,+0.000000,+0.000000

points axis +1.000000,+0.000000,+0.000000

towards ECI +0.788423,+0.567896,+0.236397

which is R.A. +35.765 Decl. +13.674

missing R.A. +42.272 Decl. +16.267 (ibex-sun)

error is R.A. +6.507 Decl. +2.593

for a total 6.799 deg

There is no overlap with orbit 0524 commands.

Command Approval Checklist is attached.

Carol

Carol Weaver

University of New Hampshire

503.902.8492

From: Nigel Angold <angoldconsulting@earthlink.net>
Date: Friday, 2021-April-9 at 12:57
To: Perry, Timothy E [US] (SP) <Timothy.Perry@ngc.com>
Cc: Weaver, Carol <Carol.Weaver@unh.edu>, Chubin, Eric [US] (SP) <Eric.Chubin@ngc.com>, Heirtzler, David <David.Heirtzler@unh.edu>, ADS-IBEX@l3harris.com <ADS-IBEX@l3harris.com>, IBEXOPS@gmail.com <IBEXOPS@gmail.com>, isocops@lists.sr.unh.edu <isocops@lists.sr.unh.edu>, fair-play@comcast.net <fair-play@comcast.net>, kwfairchild@gmail.com <kwfairchild@gmail.com>, Fairchild, Kenneth <Ken.Fairchild@unh.edu>, Paul.Janzen@mso.umt.edu <Paul.Janzen@mso.umt.edu>, Tyler, Ryan S [US] (SP) <Ryan.Tyler@ngc.com>, Wesley, Sheral R [US] (SP) <Sheral.Wesley@ngc.com>, Wynn, Reese [US] (SP) <Reese.Wynn@ngc.com>
Subject: Re: IBEX Orbit #525 ATS Approval ( 21 – 30 Apr 21)

Caution - External Email

I approve IBEX_2021_111_o0525a_BUS_v001.scr and IBEX_2021_111_o0525a_INST_v001.scr.

Nigel

All,

   Attached are the planning files for Orbit #525. Please respond to this thread with comments and approvals.

Approvals are required by COB on 09 April 2021

Please note the following:

I generated 3 separate ATS files BUS, INST and a complete file. The BUS and INST will be the files to be uplinked. The complete ATS, I used as a sanity check to see how the commands lined up. Since we are in a new phase of ATS generation. IF you have any ideas of doing this differently, let me know.

The 3 ATS files have been changed to word files and encrypted. I will send out another email with the password. The files that have been transferred via MFT have not been encrypted and are still text files.

I moved the 2 House Keeping commands from the INST ATS to the BUS ATS. I commented out the 2 commands in the INST ATS. If for some reason we were unable to uplink the INST Commands for this orbit, we would have been in the wrong spacecraft state for executing the maneuver commands.

I placed the following note in the ATS because of an overlap in the orbit 524 & 525 ATS’s. This is acceptable. The contact occurs between the execution of the Ascending Bus Commands and the Ascending payload commands.

# Note Orbit# 524 SSR_Dump/Tracking Contact 15 Asc 2021/04:21 19:30:00 - 20:30:00

Battery Balancing this orbit

Begin 2021/04:30:15:00:00– End 2021/04:30:16:30:00

# Orbit# 522 Reset Master Timer - 2021/04:12:12:45:00

APL Contact 2021-04-30,120,21:00:00 - 2021-04-30,120,22:00:00

Just a reminder for the APL contact. We start off at 2k D\L, after 5 minutes we switch to 320k D\L, Then 5 minutes later we start the SSR Dump with Dump New command

Command Load Constraint Violation Report (CCVR)

IBEX_2021_111_o0525a_v001.ccvr

# Input files:         1

#   IBEX_2021_111_o0525a_v001.scr

==========================

HARD CONSTRAINT VIOLATIONS

==========================

NO VIOLATIONS.

==========================

SOFT CONSTRAINT VIOLATIONS

==========================

IBX-CLC-016: No command to enable spin pulse protection was found after

             transition to science mode at 2021/04/21 14:16:25 UTC

IBX-CLC-016: No command to enable spin pulse protection was found after

             transition to science mode at 2021/04/25 16:58:53 UTC

Timothy E.Perry

CRS IBEX OCO-2

Mission Operations

timothy.perry@ngc.com

Office (703) 406-5976

Cell (301) 606-1430