21.9% of robot training data violates physics — we measured it.

We ran 216 RoboTurk robot teleoperation episodes through a physics checker. 21.9% failed. “This is not synthetic data. These are publicly used datasets.” Not mislabeled. Not missing values. Physically impossible motion — data that violates Newton's laws, rigid-body kinematics, or IMU internal consistency. These episodes were being used to train robot arms. What we checked Seven biomechanical laws validated per window: Newton's Second Law (F = ma coupling) Segment resonance frequency Rigid body kinematics Jerk bounds (human motion ≤ 500 m/s³, Flash & Hogan 1985) IMU internal consistency Ballistocardiography Joule heating (EMG + thermal) Each window gets a score 0–100 and a tier: GOLD / SILVER / BRONZE / REJECTED Results on real datasets Dataset Result RoboTurk Open-X (216 episodes) 21.9% rejected as physically invalid PAMAP2 (100Hz IMU) +4.23% F1 after filtering corrupted windows WESAD (stress classification) +3.1% F1 improvement UCI HAR +2.51% F1 vs corrupted baseline WISDM 2019 +1