Pluck a stretched band and follow its shrinking oscillation

Original, untested video brief. No input image or generated result is supplied.

1. Task and boundary

Pull the midpoint of a stretched elastic band slightly away from its rest line, release it once and follow several diminishing reversals. The two attachment points remain fixed throughout. End when the midpoint is nearly still around the original line, without a second pluck.

This original visual brief is untested. Use one plain band attached between two rigid supports. Exclude a traveling pulse down a long loose rope, snap-through into a second stable arch and exact frequency or damping claims. Suggested pacing is a shot plan, not a measured material response.

2. Authorized first frame

Use a photograph or accurate drawing you own or have permission to use. Show both supported band ends and one original fingertip pulling the middle a small distance downward. Leave clear space above and below the line between the supports.

Choose a frontal view with a contrasting background and a small existing midpoint mark. Keep the supports and their base contacts visible. The initial deflection should remain modest enough that the whole band and both attachments fit in the frame.

3. Use the generator

Open the current image-to-video generator in a mode accepting your authorized first frame. Paste the prompt; check settings and cost before submission. Nothing runs automatically.

4. Prompt and timing

Start from my authorized image of one elastic band stretched between two fixed supports, with the original fingertip holding its marked midpoint slightly below the rest line. Lock the camera, lighting, supports and both end attachments. Release the fingertip once and move it clear. Let the same midpoint pass back across the rest line, reverse above it, then continue through several smaller alternating deflections. Keep the band continuous and attached at both ends. The visible motion decreases toward the original straight resting line; do not grow a larger oscillation after a smaller one or leave a permanently inverted arch. Preserve the midpoint mark instead of replacing the band with a blur texture. End with the band nearly still and the finger separated from it. No second pluck, moving support, detached endpoint, traveling loose rope, cut, camera move, sound claim or numerical overlay.

1. Establish, first fifth: locate both attachments, the midpoint and the initial downward displacement.
2. Release, middle three fifths: follow successive midpoint crossings and compare the outermost deflections.
3. Settle, final fifth: inspect the nearly straight band while the fingertip remains clear.

5. Inspect the output

For each check, record a frame or time, observation and pass, fail or inconclusive judgment.

• The fingertip visibly releases before the free reversals begin.
• Both attachment points remain fixed relative to their supports.
• The same marked midpoint crosses the rest line in alternating directions.
• Later visible deflections are smaller than the early ones without an added driving contact.
• The band remains connected and ends near its original resting line.
• If blur hides the midpoint reversals, mark oscillation continuity inconclusive rather than judging a vibrating texture.

6. Fix one failure

• The supports wobble: anchor their base contacts and limit motion to the band.
• Amplitude grows again: remove repeated-pluck language and keep the finger clear after release.
• A new arch remains: ask for crossings around one rest line rather than a bistable shape change.
• The midpoint vanishes in blur: request fewer slower visible reversals and a larger existing marker.
• The ends detach: reduce initial displacement and preserve both attachment regions in view.

7. Ending and limits

Finish with the same attached band nearly still around its original line and no continuing hand contact.

Save your result, authorized input, exact prompt, settings and inspection notes.

No H3 result, resonance measurement, damping coefficient or sound synthesis is supplied. Frame sampling may hide motion; this plan cannot recover an exact oscillation rate.

The rope-pulse task follows a traveling disturbance. The snap-through task retains an inverted arch. Here a fixed midpoint region repeatedly reverses with shrinking deflection around one rest line.