[Isocops] IBEX Goat Herder for Nov 15 & 16, 2022

[Perry, Timothy E [US] (SP)]

All,
    We had a couple issues during the perigee contacts. The inertial maneuver was successful.
During the contact on 11/15/22 @00:30 USHI01 it was noted that the ACE went thru a hard reset. The reset occurred on 11/14/22 @14:18:00. The ACE was performing nominally during the contact. Normally for a soft reset we see that the ACE uptime and the thruster on time counters have reset to zero. This time we also saw that and the static z rate had reset to a default value of 4.159. It should have been set to 4.169. Since we had completed the apogee maneuver and it was an inertial maneuver the tlm point “Point inertial” should have been set to 1 instead it was set to 0. The point “Point at sun” should have been set to false and it was at true. Also, the KF_input_Selsource was set to GND_CMD vs. STA_PCT_Valid. The star tracker status flags and the estimator status flags were set to disable. We executed standing CAR #1004 “ACE reset recovery” to re-enable the ACE FDC status flags. We also reset the static z rate and reset the KF Input to STA_PCT_Valid. Post pass playback verified that the spacecraft values prior to the reset were nominal and the apogee inertial maneuver was successful.

   The USHI02 contact on 11/16/22 @19:00 started off with a negative acquisition. We changed the data rate from 160k down to 2k and the SSC NMC was able to see a downlink. Since they saw an Eb/No that was 12 db. Which was very low for a perigee contact. The NMC decided to configure USHI01 to shadow us. On the USHI01 station the Eb/No was ~30db. This is what they should be seeing during a perigee contact @2k. We requested that they reconfigure our connections to command and receive data thru USHI01. Once command was established we were able to set the downlink to 320k and dump the SSR. During troubleshooting, the issue the NMC found was that the configuration file for the down converter was incorrect. Once they configured it correctly, they saw that the receive levels for both stations were within 1 db of each other. The SSR Dump for Orbit 587 was successful with zero errors.

Tasks Accomplished:
SSR Dump -> Dump New
CAR #1004 ACE Reset Recovery
CAR # 1277 Orbit 589 ATS upload
  IBEX_2022_329_o0589a_v001 96 Commands
Reset Master Timer
Set Static Z rate
Set Kalman filter to STA Percent Valid
Dumped FC Back Orbit Data


Results from the Perigee Inertial Maneuver:
Q1 0.78891100 ActNor.EstInrToBdy[0]
Q2 -0.17835100 ActNor.EstInrToBdy[1]
Q3 -0.28080700 ActNor.EstInrToBdy[2]
Q4 0.51667900 ActNor.EstInrToBdy[3]

GPS sec 1352613660 ActNor.EstTime

UTC time 11/16/2022 06:00:46 output
MPS Diff 0.621 deg
MPS Cmd Vector X -0.624991000
MPS Cmd Vector Y -0.712615000
MPS Cmd Vector Z -0.318695000
CSS Angle TLM 2.21
CSS Sun-Pointing Angle 4.42
  12 Nov 22 at 02:00:00
CSS Angle TLM 1.07865
CSS Sun-Pointing Angle 2.1573
  16 Nov 22 at 06:00:00
Pre-Burn
Thruster 1 0 15 Nov 22 at 00:30:00
Thruster 2 0
Thruster 3 0
Thruster 4 0
Post-Burn
Thruster 1 288 16 Nov 22 at 06:00:00
Thruster 2 288
Thruster 3 336
Thruster 4 336
Number of Pulses
Thruster 1 288
Thruster 2 288
Thruster 3 336
Thruster 4 336
Thruster Pairs
Thruster 1 & 2 576
Thruster 3 & 4 672


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