All you have to know about a momentum flap !!!
No, you need to know a lot more. Here's a starter package for you:
Kinzel, W. M., 2005(A), “Managing Angular Momentum Accumulation by Visit
Sequencing and Visit Roll Selection”, JWST-STScI-000713, SM-12, Baseline
Kinzel, W. M., 2005(B), “Using Spacecraft Roll to Control JWST Momentum Buildup”,
JWST-STScI-000729, SM-12, Baseline
Kinzel, W. M., 2007, “JWST Angular Momentum Management with Pass 1 and 2 Torque
Tables”, JWST-STScI-001189, SM-12, Baseline
Long, K. S., 2005, “Comparisons of the random walk model to schedules generated with
planJ and JMS/Spike”, JWST-STScI-000663 – Rev. B
Markley, F. L., et al, 2007, “Momentum Management Working Group: Restart 1st and
2nd Pass Final Report”, 07-JWST-0210, 28 September 2007.
Mitchell, L., 2007, “Observation Efficiency Allocations Report”, JWST-RPT-004166
Rev C, June 8, 2007
Petro, L., 2005, “JWST Science Operations Design Reference Mission (SODRM) Data
Products”, Version 1.1 (S&OC-DRD OP-01), JWST-OPS-003257, October 25, 2005.
Petro et al. 2005, “Planning to Minimize Angular Momentum”, JWST-STScI-000645 –
Rev A.
Rager R., Giuliano M., 2006, “Evaluating Scheduling Strategies for JWST Momentum
Scheduling” In the Proceedings of the 5th International Conference on Planning and
Scheduling for Space. Baltimore, MD. Pages 82-91.
Simmons, D.F., et al. 2005, Momentum Management Trade Study Final Report”, 05-
JWST-0402, 26, October, 2005.
Stockman 2005, “Maximum Allowable Solar Torque Architecture for JWST, JWSTSTScI-000583
Stockman & Long 2005, A Statistical Analysis of Angular Momentum Buildup and its
impact of the JWST Science Mission, STSCI-JWST-TM-2005-0208
Don’t ask me what the JWST reaction wheels are!
The ACS uses sun sensors, star trackers, and gyroscopes to sense the observatory orientation and movement, as well as reaction wheels and/or thrusters to apply force or torque to the observatory for pointing control or maneuvers. The reaction wheels provide the control torques needed to maintain attitude and pointing as well as to slew. The spacecraft's star trackers provide stellar inertial attitude reference for 3-axis coarse pointing control. The ACS points the telescope boresight to within 8″ (1-σ, per axis) of the commanded position prior to guide star acquisition, without any position reference or input from the Fine Guidance Sensor (FGS).
Control of the roll orientation about the telescope's optical axis is provided by input from the spacecraft's 2 star trackers. The star trackers each have a ~16° diameter FOV, projected on to a 512 × 512 pixel CCD detector. They are oriented over 45° from the telescope boresight and each other. The star trackers compare the observed positions of bright stars (V < 6) to an internal star catalog. This allows the use of a single star for fine guidance within the FGS field of view (FOV) while still maintaining roll control.
The duration of slews is a function of the length of the motion. The rate of motion is determined in part by the need to keep settling times within certain limits as well as the desire to reach the new pointing as soon as possible. For slews between 25" and 3°, the slew rate is slower than for shorter or longer slews, to avoid exciting slosh modes of the propellant in the tanks. Once excited, propellant slosh can take a long time to damp (more than 20 minutes in some cases).
Fine guidance is a closed loop system, in which a guide star in the FGS FOV is used to stabilize the observatory during science exposures. The FGS makes measurements of the guide star position in the plane of the sky and sends these to the ACS every 64 ms. Using the FGS data, the ACS determines the telescope pointing error to be removed, using a combination of the fine steering mirror (FSM) and the spacecraft's reaction wheels.
Each science visit uses a single guide star. Pointing changes within the FGS FOV (dithers, target acquisition motions, etc.) are specified to the spacecraft in terms of the change in the guide star location (Delta X, Delta Y) in the FGS FOV, and the change in the position angle (Delta PA) about the guide star's position.
For stationary targets, the ACS controls the FSM and reaction wheels so that the guide star remains at a fixed location in the FGS detector.
In order to change the telescope pointing orientation by more than one FGS pixel (about 0.06"), the ACS must exit the "Fine Guide" mode, execute the pointing change, and then reestablish fine guidance. Very small offsets <0.06" can be executed by the FSM, while the ACS remains in closed-loop fine guidance control.Nothing about momentum flaps 2022.
As Boydster pointed out, does the Heiwabot really think the engineering, design, calculations for momentum flap guidance was done the day of launch in 2022? Would a Heiwabot design a tanker rudder the day it was launched into the sea? The Heiwabot really needs to upgrade from decades old idiocy and infancy.