feat(perception): geometric face emotion classifier (Issue #359)
Classifies facial expressions into neutral/happy/surprised/angry/sad
using geometric rules over MediaPipe Face Mesh landmarks — no ML model
required at runtime.
Rules
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surprised: brow_raise > 0.12 AND eye_open > 0.07 AND mouth_open > 0.07
happy: smile > 0.025 (lip corners above lip midpoint)
angry: brow_furl > 0.02 AND smile < 0.01
sad: smile < -0.025 AND brow_furl < 0.015
neutral: default
Changes
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- saltybot_scene_msgs/msg/FaceEmotion.msg — per-face emotion + features
- saltybot_scene_msgs/msg/FaceEmotionArray.msg
- saltybot_scene_msgs/CMakeLists.txt — register new msgs
- _face_emotion.py — pure-Python: FaceLandmarks, compute_features,
classify_emotion, detect_emotion, from_mediapipe
- face_emotion_node.py — subscribes /camera/color/image_raw,
publishes /saltybot/face_emotions (≤15 fps)
- test/test_face_emotion.py — 48 tests, all passing
- setup.py — add face_emotion entry point
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
sl-perception
672120bb50