ColonelMcCauley
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I'm trying to determine how the Sextant is operating in the P23 scenario. Is anyone available who either programmed this, or is familiar with the code?
I asked a broad question to first find someone who knew the Sextant itself. Now I'll ask a specific question. When the trunnion angle is reading 0-deg, what is the angle between the face of the movable Trunnion mirror and the Shaft axis? The documentation describes only the mirror Y-axis, aka Trunnion Drive axis, not the X and Z axes. During the Calibration procedure, the Landmark LOS (LLOS) and the Star LOS (SLOS) are both pointed at a single star, and the two images should be seen as one single image. If the mirror face is parallel to the shaft axis at a 0-degree Trunnion angle, how is this image transmitted to the reticle?What exactly do you want to know about? How the sextant works with its split line-of-sight, or how the computer is using the sextant data? Or something else? You are asking a very broad question.
Based on this image: https://history.nasa.gov/afj/ap08fj/pics/sextant.gif when LLOS and SLOS are pointing into the same direction, the trunnion mirror's normal vector is circa at 45 degrees to SLOS (certainly it depends on the exact orientation of the beam splitter and the prism). What we know for sure from the CDU electronics is that the angle signal of the trunnion mirror's should be taken into account twice as much as any other angle signal fed into AGC (CM Optics Shaft, IMU gimbals, LM RR angles). So a -57° to 57° trunnion range could be covered by a mirror movement between 16.5° to 73.5°.When the trunnion angle is reading 0-deg, what is the angle between the face of the movable Trunnion mirror and the Shaft axis? The documentation describes only the mirror Y-axis, aka Trunnion Drive axis, not the X and Z axes. During the Calibration procedure, the Landmark LOS (LLOS) and the Star LOS (SLOS) are both pointed at a single star, and the two images should be seen as one single image. If the mirror face is parallel to the shaft axis at a 0-degree Trunnion angle, how is this image transmitted to the reticle?
Hello There,Based on this image: https://history.nasa.gov/afj/ap08fj/pics/sextant.gif when LLOS and SLOS are pointing into the same direction, the trunnion mirror's normal vector is circa at 45 degrees to SLOS (certainly it depends on the exact orientation of the beam splitter and the prism). What we know for sure from the CDU electronics is that the angle signal of the trunnion mirror's should be taken into account twice as much as any other angle signal fed into AGC (CM Optics Shaft, IMU gimbals, LM RR angles). So a -57° to 57° trunnion range could be covered by a mirror movement between 16.5° to 73.5°.