15.119 14.5.10 Orientaciones y ángulos articulares
Las recomendaciones ISB buscan estandarizar cómo reportar cinemática
y sistemas articulares [P45-R4, P45-R5, P45-R6]. El modelo canónico
conserva una rotación en SO(3) y genera vistas articulares
interpretables con convención declarada.
ΔR = R(t_k)^T R(t_{k+1})
ω ≈ Log(ΔR)∨ / Δt- representation: rotation matrix or quaternion as canonical; JCS angles as interpretable view; optional helical axis for finite rotations
- requiredMetadata: parent segment; child segment; segment frame construction; rotation sequence/JCS; positive directions; units; singularity policy
- singularityPolicy: Near a decomposition singularity, preserve canonical rotation and flag Euler/JCS components as ill-conditioned.
- rangePolicy: Do not impose clinical ROM limits as hard truth for vision; use them as soft QA with athlete/context awareness.
- handPolicy: Finger joint angles require hand landmarks or a hand model; body-only wrist points do not identify grip configuration.
Un ángulo de hombro o cadera no es reproducible si no se conoce el frame del segmento, el parent, el child, la secuencia y el signo.