Computer vision and AI-driven movement analysis.
Part 3 of Avatar Talk: retarget MediaPipe pose landmarks onto a VRM avatar’s bone rotations, in the browser. Positions vs rotations, the MediaPipe→VRM coordinate flip and mirror, rest→target quaternions, world→local chains, frame-rate-independent easing, and the single-camera depth fix.
Part 2 of Avatar Talk: load a real 3D VRM avatar in the browser with three.js and @pixiv/three-vrm. Why VRM’s standardized bone map matters, the loading cleanup that counts on a 15 MB model, two-line breathing, and the expression system for lip sync.
Real-time motion capture in the browser — no install, no server, about 200 lines of TypeScript. Part 1 of Avatar Talk: a webcam, a transparent canvas, and MediaPipe’s PoseLandmarker drawing a live upper-body skeleton, with the two gotchas that make it work.
Two 2026 papers take opposite bets: SoccerNet pools 427 teams and 1,129 submissions onto one shared benchmark, while a skateboarding study checks one commercial IMU against lab references — with mixed results.
Two reviews and one study show the distance between what AI-plus-wearables promises for injury prediction and what exists: a good classifier of expert judgment (0.86 AUC) — not a validated predictor of a future injury.
Cameras got cheap. Three 2026 studies — a 3D reconstruction pipeline, a systematic review, and one smartphone — all point the same way: global, gross measures are within reach; fine timing and joint angles are not, at any price point.
Wearable mocap used to mean a 17-sensor suit. Four 2026 studies ask the smallest set that still works: running needs 1–3 sensors, jump testing needs 1, base-running and hammer throw need more — and none was tested across all four.
CalTennis is the first large-scale sports benchmark for monocular-to-3D pose estimation: 40 players, 11M+ synchronized frames. The finding is a dissociation — relative joint angles pass, but depth and foot contact fail systematically, exactly where injury risk lives.
Four 2026 papers ask whether one phone camera can replace force plates, MoCap suits and EMG: OpenCap Monocular, BioHuman, From Pixels to Newtons, and Pose-to-Biomechanics — plus why upstream pose accuracy is the ceiling on all of them.
Three 2026 papers on getting biomechanics out of the lab: Ultra Diffusion Poser (full-body pose from IMUs + UWB, zero cameras), biomechanics-aware markerless hand capture, and a wearable study auditing the VR reality gap — plus the open question each one leaves behind.