NOAA Office of Satellite and Product Operations

NOAA 15 ADACS Subsystem Summary

Component Description Status
GYRO 1Gyroscopic Rate Measuring Device #1 (YA, ZA)Green
GYRO 2Gyroscopic Rate Measuring Device #2 (XA, ZB)Orange
GYRO 3Gyroscopic Rate Measuring Device #3 (XB, YB)Yellow
IMUInertial Measurement UnitGreen
PTC 1APitch Torque Coil 1AGreen
PTC 1BPitch Torque Coil 1BGreen
PTC 2APitch Torque Coil 2AGreen
PTC 2BPitch Torque Coil 2BGreen
RWA SSkew Reaction Wheel AssemblyGreen
RWA XX-axis Reaction Wheel AssemblyGreen
RWA YY-axis Reaction Wheel AssemblyGreen
RWA ZZ-axis Reaction Wheel AssemblyGreen
RYTC 1ARoll-Yaw Torque Coil 1AGreen
RYTC 1BRoll-Yaw Torque Coil 1bGreen
RYTC 2ARoll-Yaw Torque Coil 2AGreen
RYTC 2BRoll-Yaw Torque Coil 2BGreen
SSASun Sensor AssemblyGreen

Subsystem History:

Date Time Component Description
08/11/201420:30:00 Clear Consistency Flag
01/25/201219:53:53 End GYROLESS test
01/24/201218:53:14 Start GYROLESS test
11/30/201120:49:52 End GYROLESS test
11/29/201114:49:10 Start GYROLESS test
03/15/201016:53:06 Set RYC to use primary coil
03/11/201019:51:30 Pitch Wheel Bias set to 2500 RPM to enhance RGYRO performance (Non-Control SCP)
03/11/201019:51:00GYRO 2Pitch Wheel Bias set to 2500 RPM to enhance RGYRO performance (Non-Control SCP)
03/11/201001:41:16 Pitch Coil Swap to Back-up
03/11/201001:28:36RWA ZPitch Wheel Bias set to 1300 RPM to enhance RGYRO performance (Control SCP)
03/11/201001:25:55RWA ZPitch Wheel Bias set to 1300 RPM (Non-Control SCP)
03/10/201023:49:54 Reduced gyro estimate X, #2 Gryo Off
03/10/201023:47:29 Disable Thrusters
03/08/201001:45:56 automatic switch to YGC
06/04/200917:08:00 Enables Auto Thruster Firings for both CPUs
06/04/200917:07:00 Change gas unloading threshold for pitch axis momentum from 40 in/lbs/sec to 45 in/lbs/sec for both CPUs
06/30/200612:00:00RWA ZZ-reaction wheel transition toward positive values reversed. Trending back toward negative values. Wheel continues sticking as it passes through 0 RPM.
06/17/200612:00:00RWA ZWhenever the Z-wheel speed passes through 0 RPM, in either direction, the wheel sticks for up to several minutes impacting pitch precision. Expect transition to full positive values on or about 5 Jul 06.
06/01/200612:00:00RWA ZZ-reaction wheel (pitch) transitioning from a negative direction to a positive direction (for the first time ever). Pitch torquer coil intervention no longer required.
06/03/200418:25:00 Revised Mag. torquer constants to non control SCP
04/22/200418:20:00 Reduced gyro testing completed. Estimating all 3 axis successfully tested.
04/22/200416:45:00 Command ADACS to nominal mode.
04/22/200416:40:00 Ends estimate yaw-pitch test
04/22/200413:20:00 Ends estimate yaw test
04/22/200413:20:00 Preparatory commands for Yaw-Pitch estimate Rgyro test.
04/21/200412:03:00 Preparatory commands for Yaw Estimate Rgyro test
04/20/200423:46:00 Ends roll-pitch test
04/20/200422:05:00 Preparatory commands for Roll-Pitch estimate Rgyro test
04/20/200417:25:00 End estimate roll test
04/19/200422:30:00 Ends estimate pitch test
04/19/200416:05:00 Preparatory commands for pitch estimate and roll estimate Rgyro tests
04/19/200416:00:00 Start Reduced gyro testing series. Pointing precision during testing may be impacted. Testing is day shift (eastern time) 19, 20 and 22 Apr. 24 hour test on 21 Apr.
10/15/200319:40:00 Command N15 back to NOMINAL attitude control mode, test complete.
10/15/200316:15:00 Command N15 to YGC mode for baseline performance test.
03/15/200220:00:00GYRO 3Gyro 3 Turned OFF- test complete
03/11/200216:45:00GYRO 3Gyro 3 Turned ON for data gathering purposes
10/10/200116:45:00 Placed spacecraft back into normal ADACS mode
10/09/200113:51:00 Forced spacecraft into YGC mode
06/26/2000GYRO 3Gyro 3 powered off because of erratic readouts.
05/13/199816:24:00ESAOn Orbit
05/13/199816:24:00GYRO 1On Orbit
05/13/199816:24:00GYRO 2On Orbit
05/13/199816:24:00GYRO 3On Orbit
05/13/199816:24:00IMUOn Orbit
05/13/199816:24:00PTC 1AOn Orbit
05/13/199816:24:00PTC 1BOn Orbit
05/13/199816:24:00PTC 2BOn Orbit
05/13/199816:24:00PTC 2AOn Orbit
05/13/199816:24:00RWA SOn Orbit
05/13/199816:24:00RWA XOn Orbit
05/13/199816:24:00RWA YOn Orbit
05/13/199816:24:00RWA ZOn Orbit
05/13/199816:24:00RYTC 1AOn Orbit
05/13/199816:24:00RYTC 1BOn Orbit
05/13/199816:24:00RYTC 2AOn Orbit
05/13/199816:24:00RYTC 2BOn Orbit
05/13/199816:24:00SSAOn Orbit