Storyboards for GP-B Animations Bob Kahn & James Overduin July 6, 2007

Transcription

1 Storyboards for GP-B Animations Bob Kahn & James Overduin July 6, 2007 Changes in this Version: Scene 4 - Slide 5b Corrected; See page 24. July 6, 2007 GP-B Animation Storyboards Page 1

2 Seven GP-B Animation Scenes 1. Newton s view of space & time; Action at a distance Gravity in Newton s universe 2. Einstein s view of spacetime; Following a geodesic Gravity in Einstein s universe 3. A Simple Experiment: A star, a telescope & a spinning ball 4. Using Superconductivity to monitor gyro spin-axis orientation 5. From gyro to payload to spacecraft to orbit (assembling the parts, launching the spacecraft, acquiring the guide star, and orbiting for a year.) 6. The Drag-Free Satellite 7. How big is a milli-arcsecond in human terms? Note: Some animation scenes are based on earlier animations created by Norbert Bartel and Adam Jeziak for the movie, Testing Einstein s Universe. July 6, 2007 GP-B Animation Storyboards Page 2

3 Scene 1 - Slide 1: Newton s space & time Start with full-screen portrait of Newton on starfield (include name and dates of birth/death) Shrink head & shoulders vignette to corner of scene Bring up earth, rotating on radial grid, shallow view, suggesting infinite expanse of space Bring up caption July 6, 2007 GP-B Animation Storyboards Page 3

4 Scene 1 - Slide 2: Action at a Distance To previous image, add spinning gyro ball, orbiting earth in the path shown by the yellow orbit line (Q: Should yellow orbit path line be visible or fade out?) Grid lines on ball indicate that it is spinning counter-clockwise along an axis tangent to the orbit at starting point. The force arrows orbit with the ball. The Action at a distance? caption appears, the scene freezes for a few seconds, and then the animation resumes as Action at a distance? caption fades out. July 6, 2007 GP-B Animation Storyboards Page 4

5 Scene 1 - Slide 3: Spin axis fixed A spin axis arrow appears through the poles of the gyro, as the gyro rotates and orbits the earth At the same time the arrow appears, a caption appears on screen saying that a gyro spin axis remains fixed with respect to absolute space. The spin axis arrow always points in the same direction, consistent with the grid lines on the rotating sphere. The attractive force arrows continue to orbit with the ball. July 6, 2007 GP-B Animation Storyboards Page 5

6 Scene 2 - Slide 1: Einstein s Spacetime Use color image of Einstein Start with full-screen portrait on starfield Shrink head & shoulders vignette to corner of scene Bring up earth, static (not rotating) on radial grid, shallow view, suggesting infinite expanse Animate warping of spacetime grid, with earth sinking slightly into grid Add caption about space and time being relative & interwoven into a fabric called spacetime. July 6, 2007 GP-B Animation Storyboards Page 6

7 Scene 2- Slide 2: Einstein s Spacetime Zoom scene camera out slightly and tilt up to show higher view of earth s gravity well Start the earth rotating counterclockwise Add caption about spacetime telling matter how to move Note: Move grid and earth higher on page to make room for caption. Animate the counterclockwise twisting of the spacetime grid. The twisting is most prominent at the center of the grid and falls off quickly as you move further out (proportional to the radius cubed) Change caption: Massive rotating bodies, like the Earth, warp and twist their local spacetime. July 6, 2007 GP-B Animation Storyboards Page 7

8 Scene 2-Slide 3: Traveling on a Geodesic Trac out out an equatorial geodesic path around one of the circles in the spacetime grid. If possible, have the path appear as if someone took a pen and traced around the circular geodesic grid line. Bring up caption about objects orbiting in curved geodesic paths. Animate the geodesic path, tipping up on a horizontal axis through the center of the Earth, so that the path changes from equatorial to polar orientation. Display the gyro ball, rotating counter-clockwise on its own spinaxis which is tipped up a bit, as it orbits the Earth on the polar geodesic path. July 6, 2007 GP-B Animation Storyboards Page 8

9 Scene 2 - Slide 4: Geodetic Precession Animate gyro, rotating counterclockwise, together with white spin-axis pointer, orbiting earth. Caption explains precession of the spin axis over time. A 2nd colored pointer marks the gyro s initial direction as the white pointer opens an increasing angle with each successive orbit. The final geodetic precession angle, in the plane of the orbit after a year, is 6,606 milliarcseconds, as indicated by the final angle and captions. July 6, 2007 GP-B Animation Storyboards Page 9

10 Scene 2- Slide 5: Frame-dragging Precession Zoom out and tilt scene camera up to bird s eye view, looking down on top view of rotating earth and surrounding spacetime grid. Show rotating gyro, with spin-axis pointer moving forward and backward, alternating above and below earth to indicate polar orbit. Caption describes gyro precession from twisting spacetime Slowly animate counter-clockwise twisting of spacetime grid. Use white spin-axis indicator to show initial pointing position, and show slow precession of red pointer relative to white pointer, due to precession. Show final frame-dragging angle 0f 39 milli-arcseconds/yr and caption. July 6, 2007 GP-B Animation Storyboards Page 10

11 Scene 2 - Slide 6: Combined Measurements Combine scenes 4b and 4c together in a perspective view Zoom in so that gyro is prominent (enlarge gyro, if necessary) The gyro s spin axis is pointing out of the frame, towards you, and it is spinning counter-clockwise as it orbits counterclockwise around the earth s poles. The earth is also rotating counter-clockwise, and spacetime is twisting in the same direction. The yellow spin-axis arrow begins on top of the white (reference) arrow. The spin axis arrows need to be long enough to exaggerate the effects. The initial (white) caption explains that the two effects occur at right angles to one another. The colored captions appear after an orbit or two, explaining the colored arrows that are opening up. July 6, 2007 GP-B Animation Storyboards Page 11

12 Scene 2 (Continued) - Slides 6c & 6d Slide 6c shows the angles from slide 6b gradually opening further as more orbits progress. The initial caption fades out, and the animation continues for a total of 4-5 orbits long enough for people to read the captions and grasp the concept, but not so long that the spin-axis deflection angles grow larger than those shown in these storyboards. As we reach the final angles, the colored captions fade out. For Slide 6d, the final scene, we zoom in on the gyro and earth to exaggerate the final annual deflection angles. Bring up the final deflection angle values, and freeze this frame long enough for people to read both captions. Fade to black. July 6, 2007 GP-B Animation Storyboards Page 12

13 Scene 3 - Slide 1 Simple Experiment Earth crescent in lower right corner rotates counterclockwise about its axis (offscreen); stars remain fixed Caption begins Fairbank quote In slide 1b, first line of caption rolls up and disappears as 2nd line begins It s just a star A bright star appears in upper left corner of screen (image pictured is a photo of the guide star IM Pegasi) corresponding with emerging 2nd line of caption. July 6, 2007 GP-B Animation Storyboards Page 13

14 Scene 3 - Slide 1 (Cont.) In Slide 1c, caption continues to build It s just a star, a telescope Telescope appears, corresponding to caption In slide 1d, caption completes as shown. Gyro spinning counter-clockwise appears, with completed caption. Note: Gyro surface needs to be marked somehow (e.g. grid lines or arrows) so you can tell that it s spinning. Note: Star, telescope, & gyro need to be aligned, but can be repositioned along that line as needed I.e. they can be moved towards the star a bit more. July 6, 2007 GP-B Animation Storyboards Page 14

15 Starlight beams into telescope Note: It should not look like the telescope is shooting at the star (it s starlight, not a laser beam); make the beam look somewhat diffuse with particles streaming towards the telescope. Bring up caption as shown Note: Both Earth & gyro continue their rotating motion throughout this entire sequence. Scene 3 - Slide 2 July 6, 2007 GP-B Animation Storyboards Page 15

16 Transitioning from Slide 2, the caption changes to explain the role of the telescope A spin-axis arrow appears on the spinning gyro, initially aligned with the guide star. As we progress from Slide 3a to Slide 3b, the spin axis orientation changes, moving both towards the viewer slightly (frame-dragging precession) and down from the guide star reference line (geodetic precession). Use same technique for showing gyro spin-axis precession as in Scene 4b, since this is basically the same view. Scene 3 - Slide 3 July 6, 2007 GP-B Animation Storyboards Page 16

17 Fade away the spinaxis arrows from Slide 3, and transition caption to Simple in concept Begin shrinking both telescope and gyro, and then add 3 more gyros; the telescope and gyros should end up in their proper position inside the spacecraft, a cutaway of which will now begin to fade into view. Scene 3 - Slide 4 July 6, 2007 GP-B Animation Storyboards Page 17

18 Scene 3 - Slide 4 (Cont.) As the Simple in concept caption completes, fade in a cutaway side view of the spacecraft, so that the telescope and gyros end up properly positioned at center and towards the bottom of the dewar. Note: the cutaway of the spacecraft can be much less complete than the one shown. The idea is to show the relative positions of telescope and gyros inside the spacecraft, which is oriented towards the guide star as it orbits the Earth. In the final slide, the cutaway closes up, showing only the spacecraft. July 6, 2007 GP-B Animation Storyboards Page 18

19 Scene 4- Slide 1 Gyro Readout Show a spinning glass (quartz) gyro ball. The ball is spinning fast, counter-clockwise about an axis pointing towards 9:00 At top of screen, bring up caption 1: How can one monitor the spin axis orientation of a near-perfect spherical quartz gyro with no markings? Fade in caption 2 at bottom of screen: The answer lies in superconductivity. July 6, 2007 GP-B Animation Storyboards Page 19

20 Fade out original captions and fade in new top caption: Coat the gyro with a thin film of superconducting niobium. Animate a color/texture change of the gyro surface from translucent glass to shiny metallic (niobium coated), with grid lines or arrows to indicate the fast spinning ball. Fade in magnetic field lines around gyro and the spin-axis arrow. Bring up lower caption: A spinning superconductor develops a magnetic London moment exactly aligned with its spin axis. Scene 4 - Slide 2 July 6, 2007 GP-B Animation Storyboards Page 20

21 Scene 4 - Slide 3 SQUID Readout Fly in pick-up loop around gyro equator, connected to a readout. The pick-up loop rotates around the gyro s spin-axis, in the same direction as the gyro, but it rotates much more slowly. The rotation collar of the pick-up loop is connected to a SQUID readout display, which looks like an oscilloscope. Top Caption appears: The London moment is used to measure the spin-axis precession of the gyros. The pick-up loop rotates about the spinning gyro, but until the spin-axis and magnetic field begin to deflect downward, the readout remains a flat line. July 6, 2007 GP-B Animation Storyboards Page 21

22 Transitioning from Slide 3b, the gyro, spin axis line and magnetic field lines all now begin to rotate slightly counterclockwise. The amplitude of the readout signal begins to increase proportional to the increasing deflection of the gyro spin axis. Note: The period of the readout signal corresponds to rotation rate of the pick-up loop. The sine wave starts when the loop is horizontal, and one complete sine wave corresponds to one complete rotation of the loop. Scene 4 - Slide 4 July 6, 2007 GP-B Animation Storyboards Page 22

23 Zoom out from Scene 4b and dissolve to scene with all 4 gyros lined up, each with its own pickup loop and readout. If possible, show the quartz block, which houses the gyros in the background. This can be done in wireframe or using transparency to show that the gyros are lined up along the central axis. If it s too hard to model this, you can omit the quartz block from Slides 5a & 5b. Show that the pick-up loops for gyros 3 and 4 are offset 90 degrees from the pick-up loops for gyros 1 and 2, due to the way the 2 pairs of gyro housings are mounted in the block. Note that the spin directions of the gyros alternate: gyros 1 and 3 spin counterclockwise; gyros 2 and 4 spin clockwise (right hand rule applies to their spin axes.) All four pick-up loops rotate counter-clockwise, in unison along with the quartz block (if shown). The collars on the pick-up loops allow them to rotate, while the readout boxes remain fixed. As long as the gyro spin axes are horizontal, there is only a flat signal on the readout screens. Scene 4 - Slide 5 July 6, 2007 GP-B Animation Storyboards Page 23

24 Scene 4 - Slide 5 (Cont) After a couple of complete rotations of the pick-up loops (and quartz block, if shown), slowly begin to deflect the gyro orientations, along with their spin axis pointers and magnetic field lines, as shown. As the gyro spin axes deflect, signals appear on the readout displays. As in Slide 4, the amplitude of the readout signals grows in proportion to the spin-axis deflection angles. Note that the sinusoidal readout signals are in different phases from each other, due to the differences in spin directions and pick-up loop orientations. July 6, 2007 GP-B Animation Storyboards Page 24

25 Zoom out, while enclosing the quartz block and gyros in a cutaway or wireframe of the spacecraft, showing the location of the gyros inside. Roll the spacecraft along its central axis (which is what causes the pick-up loops to rotate). As the cutaway region rolls out of view, fade in the spacecraft skin, and zoom out further to show the spacecraft rolling next to a corner of the Earth (like in Scene 5) and pointing towards the guide star. Scene 4 - Slide 6 July 6, 2007 GP-B Animation Storyboards Page 25

26 Scene 5 From Gyro to Orbit Re-create, in reverse, Norbert Bartel s animation zooming from the outside of the spacecraft inside, layer by layer, down to the four gyros. (A reversed copy of this sequence is available for viewing in the Storyboards folder on our GP-B Web server.) In other words, re-create this sequence in reverse, starting with a gyro and building up to the complete spacecraft and then summarize the whole mission, as described below. Show the spacecraft launch (real video) Show separation & orbit acquisition Show guide star capture and rolling spacecraft orbiting earth Show earth and spacecraft orbiting the sun for a year (use animated calendar etc. to show time passage.) July 6, 2007 GP-B Animation Storyboards Page 26

27 Scene 6: Drag-free Flight Slide 1 Earth is rotating counterclockwise GP-B spacecraft orbits Earth counterclockwise The spacecraft s body axis is tilted up 23 degrees from horizontal, and it maintains this attitude throughout its orbit The spacecraft rolls slowly, counterclockwise along its body axis as it orbits. July 6, 2007 GP-B Animation Storyboards Page 27

28 Scene 6 Slide 2a Zoom in on spacecraft in orbit to a camera vantage point parallel to the spacecraft. The spacecraft is continually rolling along its axis and moving downwards, following the golden geodesic orbit line. The camera is moving next to the spacecraft, so the spacecraft remains fixed in the field of view. Perhaps the orbit line can be made of particles that appear to be moving upward. The Earth appears to be rotating both on its axis and upwards, opposite the spacecraft s motion. The stars may also appear to be slowly moving upwards if this doesn t make the viewer seasick. July 6, 2007 GP-B Animation Storyboards Page 28

29 Scene 6 Slides 2b & 2c The spacecraft is suddenly bombarded with solar radiation, causing it to recoil slightly opposite the direction of the radiation hit. Earth s atmosphere (wisps of cloud) also jostles the spacecraft, causing it to recoil opposite to the direction that the cloud strikes the vehicle. The concept to get across is that the spacecraft does not enjoy a smooth ride along the geodesic path rather, it gets buffeted around by the solar radiation and Earth s atmosphere. Note: If the spacecraft s rolling in orbit is confusing or distracting, we can turn it off until the last slide. July 6, 2007 GP-B Animation Storyboards Page 29

30 Solar radiation and atmospheric disturbances continue to strike the spacecraft at random intervals, slightly jostling the spacecraft s position on the geodesic orbit line The text caption sets up the next series of slides. Scene 6 Slide 2d July 6, 2007 GP-B Animation Storyboards Page 30

31 The outside shell of the spacecraft dissolves to a cutaway, showing the inside of the dewar, a single gyro, and four sensors. Note 1: This is a very simplified and stylized, rather than a realistic view of the interior of the spacecraft; it is designed to clearly demonstrate the drag-free concept. Note 2: For all of the cutaway slides, the geodesic orbit line is shown running through the center of the spacecraft and the gyro inside. This clearly shows that the gyro remains centered on the geodesic, while the whole spacecraft moves around it. The gyro and sensors are scaled up in size so that together, they fill the dewar s cavity. Again, this is a conceptual, rather than realistic depiction. The spacecraft should not be rotating along its axis in these cutaway slides. Scene 6 Slide 3a July 6, 2007 GP-B Animation Storyboards Page 31

32 Scene 6 Slides 3b & 3c Solar radiation is shown striking the spacecraft, which moves the vehicle in the opposite direction. This vehicle motion causes two of the sensors to move close to the gyro. We show these sensors changing color to emphasize that they are responding to the vehicle motion that is, they have moved too close to the gyro, and they are signaling the guidance system to move the spacecraft back to a centered gyro position. In response to the sensor signals, the appropriate micro-thrusters increase their flow of helium. Again, this is highly exaggerated to make the concept clear. As the thrusters fire, the spacecraft begins moving back towards its original centered position. Throughout all of this motion, the gyro clearly remains centered on the geodesic orbit line. July 6, 2007 GP-B Animation Storyboards Page 32

33 Scene 6 Slides 3d & 4a These two slides are identical and should actually be just one slide. When the thrusters finish firing following slide 3c, the spacecraft and sensors move until they are once again centered around the gyro. The spacecraft remains in this position until the next solar radiation or atomospheric disturbance event. July 6, 2007 GP-B Animation Storyboards Page 33

34 Scene 6 Slides 4b & 4c These two slides are just like Slides 3b & 3c, only this time, the spacecraft movement is due to atmospheric disturbance, rather than solar radiation. The atmospheric strike originates on the Earth side of the spacecraft, rather than the Sun side. Thus, the spacecraft moves closer to the bottom sensor, rather than the top sensor. Activation of these two sensors causes the guidance system to fire a different set of thrusters to move the spacecraft back to a centered position. July 6, 2007 GP-B Animation Storyboards Page 34

35 As in Slide 3d, after the thrusters finish firing, the spacecraft and sensors move back to their correct position, centered around the gyro. The solar radiation/atmospheric disturbance strikes and corresponding spacecraft motion, sensor alerts, thruster firings and spacecraft recentering can now be shown a couple more times, as people read the caption in Slide 4d about GP-B s unique drag-free qualities. Scene 6 Slide 4d July 6, 2007 GP-B Animation Storyboards Page 35

36 Scene 6 Slide 5 In Slide 5, we close up the cutaway, once again showing the outside of the spacecraft. We send the geodesic orbit line back behind the spacecraft. We re-start the spacecraft s rotation, (if we decide to have it rotating at the beginning in Slides 2a, 2b, 2c & 2d. Perhaps show a final solar radiation strike, with corresponding spacecraft motion, now with the viewer knowing what is going on inside. We end this scene here or perhaps zoom back out to the original orbiting depiction in Slides 1a & 1b. July 6, 2007 GP-B Animation Storyboards Page 36

37 Scene 7 How Big is a Milli-Arcsecond? This animation will be a replacement for Norbert Bartel s NY to Paris clip that showed the size of 1/10 of a milli-arcsecond. Note that this clip will show an angle 10 times larger than the NY to Paris clip. Two visual analogies hold the most promise for this clip: An astronaut in a spacesuit (7 tall), standing on the moon as viewed from Earth, measured to an accuracy of a button The width of a strand of human hair viewed from miles If possible, we should also indicate the accuracy level of the measurement (e.g. a button on the astronaut s spacesuit) One possible approach is to come up with a series angular measurements of, say a 7 tall suited astronaut, starting at a distance representing an angle of 45 degrees, and then decreasing the angle and corresponding distance of the astronaut, until we reach arcseconds at the distance of the moon. July 6, 2007 GP-B Animation Storyboards Page 37