Domain: Engineering — Materials Science & Engineering
Target concept: The shape memory alloy returns to its original shape after being heated with hot water.

Video generation prompt: Bend a small shape memory alloy wire into an elliptical shape at room temperature, then immerse the alloy wire in a large transparent beaker containing hot water, and observe the change in the shape of the wire.

Evaluation guide:
(i) Target concept: Thermally induced solid-state phase transformation enabling reversible macroscopic shape recovery in NiTi-based alloys.
Minimum mechanism: The alloy must be in martensitic phase (deformable at room temperature) and heated past Af temperature to trigger austenite reversion, causing spontaneous mechanical work that restores the parent shape; no chemical reaction, phase separation, or fluid-phase transition involved.
(ii)Storyline: Frame 0–2: Static shot showing hand placing pre-bent elliptical wire onto beaker rim or just above water surface; wire geometry is unambiguously closed elliptical loop. Frame 3–4: Wire descends smoothly and fully enters hot water. Full submersion confirmed by complete disappearance of wire above surface and consistent meniscus. Frame 5–9: Continuous, monotonic unwinding of ellipse into straight configuration, occurring entirely underwater; no pause, reversal, or fragmentation; thermal cues (steam/shimmer) persist synchronously. Perspective: Fixed frontal view, centered on beaker; entire wire always fully visible inside beaker; no occlusion by hand, lid, or other objects after immersion begins.

Manual:
Experimental Procedure
1. Bend a thin shape memory alloy wire into a clear elliptical shape at room temperature.
2. Place the elliptical wire into a large transparent beaker filled with hot water.
3. Observe the wire as it returns to its original straight shape.
Observation of Experimental Phenomena
The wire visibly transforms from an elliptical shape to a straight shape while fully submerged in hot water; no bubbling, melting, or color change occurs.
Summary of Experimental Principles
Shape memory alloys possess a thermally triggered phase transformation: heating above austenite finish temperature causes recovery of the memorized (original) shape.

Prompt Grounding rubric:
level_1: No shape-memory alloy wire is shown, or no transparent beaker with liquid appears, or the wire is never immersed in the liquid, or the wire is never shown bent into an elliptical loop. At least one of the three required elements (bent wire, transparent beaker, liquid) is missing from the clip.
level_2: The wire, the transparent beaker, and a liquid all appear somewhere in the clip, but the wire is never shown bent into a clear, closed elliptical loop before it touches the water, or the act of placing the wire into the water is never shown (the wire is simply already submerged when the clip begins), or the order of events (bend first, then immerse) is not depicted.
level_3: The wire is clearly bent into an elliptical loop before immersion, the beaker is transparent and holds a visible liquid, and the wire is placed into that liquid; but the liquid never shows a visible sign of being hot (no rising steam, no shimmer above the surface, no gentle surface motion) anywhere in the clip.
level_4: The wire is shown as a clear elliptical loop before immersion, is fully submerged in the beaker's liquid, and the liquid shows at least one visible heat cue (steam, surface shimmer, or gentle surface motion); the camera keeps the wire and beaker in frame through the immersion and the following seconds, but the shot includes a brief cut, a zoom, or a moment where the wire is partly hidden by glare, bubbles, or the beaker's rim.
level_5: The wire is unambiguously elliptical before touching the water, is fully and continuously submerged in the transparent beaker's visibly hot liquid (steam and/or surface shimmer clearly present) for the whole clip, and the camera holds one uninterrupted frontal shot with the wire, beaker, and liquid surface all continuously visible: no cuts, no swapped objects, and no moment where the wire is fully hidden from view.

Scientific and Causal Correctness rubric:
level_1: The wire shows no shape change at all and stays elliptical for the whole clip, while the water in the beaker looks cold (a flat surface, no rising steam, no heat shimmer), with nothing linking the immersion to any change in the wire.
level_2: The wire changes shape, but the wrong way (it bends further, kinks, or crumples instead of straightening), or the shape change happens before the wire touches the water or after it has been lifted back out, or the water clearly looks cold (no steam, no shimmer) while the shape change is happening, breaking the link between heating and the change.
level_3: The wire starts as a clear elliptical loop, is placed in the water, and only begins changing shape once it is fully submerged; the straightening moves in one consistent direction (elliptical, then less curved, then straighter), but the final shape is ambiguous: for example it stops at some in-between bend whose final angle is unclear, or the straightening visibly halts partway with no clear end state; nothing contradictory happens (no melting, no color change, no bubbling).
level_4: The wire starts elliptical, and once fully submerged the straightening proceeds continuously in one direction with no pause, reversal, or back-and-forth wobble; by the end the wire is noticeably straighter than its starting ellipse; the wire does not change color, dissolve, or break apart; and the heat cues (steam and/or surface shimmer) are visible and line up in time with when the straightening begins.
level_5: The wire starts as a clean elliptical loop, and as soon as it is fully submerged the straightening begins and proceeds continuously with no pause or partial reversal until the wire reaches a fully straight (or near-straight, matching its original un-bent shape) final form; no implausible side effects occur (no color shift, no bubbling, no splashing, no change in how clear the liquid looks), and the steam/shimmer heat cues stay visible for the entire immersion and straightening process, not just at the start.

Spatiotemporal Consistency rubric:
level_1: The wire or the beaker appears, disappears, or jumps to a new position between frames with no motion shown connecting the two positions; the lighting suddenly shifts partway through the clip; the background or camera angle changes abruptly; or the wire visibly breaks apart and reassembles.
level_2: The wire or beaker changes size or rotates in a way the fixed camera view can't explain; the water level jumps up or down between frames with no visible cause; the wire's position shifts with no in-between motion shown; steam appears or vanishes instantly instead of fading in or out; or the wire appears to bend at a kink or joint with no physical explanation.
level_3: The wire stays inside the beaker for the whole immersion, the beaker itself does not move, and the water level stays constant; the wire's motion during straightening looks smooth, with at most one or two brief hiccups (for instance a single flicker, or the wire's shadow briefly not matching its position) that don't break the overall sense of continuity.
level_4: There is no teleporting, no object breaking apart, no sudden lighting jump, and no perspective glitch anywhere in the clip; the wire's straightening looks physically smooth and continuous, the water surface moves only in small, gentle, consistent ripples, and steam rises without interruption; the only shortcoming is one small, brief flaw, such as a single frame where steam briefly hides part of the wire or a reflection on the beaker's glass looks slightly off for an instant.
level_5: The wire's shape evolves smoothly and continuously from elliptical to straight with no visible jump or gap in the motion; the beaker stays perfectly still with its reflections and the way light bends through the glass and water staying consistent; the water keeps a natural curve where it meets the beaker wall (meniscus) and a steady heat shimmer for the whole clip; steam rises at a steady, even rate from start to finish with no sudden start or stop; and every shadow, highlight, and reflection stays consistent with one fixed camera and an unchanging light source.