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Backhand · skeleton + HUD

Your backhand on video. Skeleton from MediaPipe; HUD is Apple Watch wrist gyro under LabWired wrist peak-detection. Graphics are only the overlay — not a simulated player.

Playback

Skeleton and HUD on the same frames. Racket speed / ball spin appear only after contact. Red marks are LabWired L∞ > 10 rad/s edges on wrist gyro.

Where each part comes from

Video: Phone clip swing1, 31shot_20260104 (operator-verified backhand)
Skeleton: MediaPipe pose landmarker on this clip
Wrist gyro / accel: Apple Watch session watch_20260104_185001 (window around Zepp epoch)
Racket speed / spin: Zepp CSV 20.9 mph · ball_spin 2.5 — shown only after contact
Peak edges: LabWired + wrist_peak_detection.elf · L∞ > 10 rad/s · edges @ [46, 51]
Not in this demo: Handle Zepp origins (serve only) · MuJoCo body