feat: UWB follow-me system (#57) — saltybot_uwb package + sensor fusion
New packages
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saltybot_uwb_msgs (ament_cmake)
• UwbRange.msg — per-anchor range reading (anchor_id, range_m, raw_mm, rssi)
• UwbRangeArray.msg — array of UwbRange published on /uwb/ranges
saltybot_uwb (ament_python)
• ranging_math.py — pure triangulate_2anchor() (height-compensated TWR
geometry, 2-anchor intersection) + KalmanFilter2D
(constant-velocity, numpy-free, 16 tests pass)
• uwb_driver_node.py — SerialReader threads poll MaUWB ESP32-S3 DW3000
anchors via AT+RANGE?, triangulate, Kalman-smooth,
publish /uwb/target (PoseStamped/base_link) + /uwb/ranges
• config/uwb_config.yaml, launch/uwb.launch.py
• test/test_ranging_math.py — 16 unit tests (triangulation + Kalman), all pass
Updated saltybot_follower
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• person_follower_node.py — adds fuse_targets() pure helper + /uwb/target
subscriber (primary, weight=0.7); /person/target secondary (weight=0.3);
weighted blend when both fresh, graceful fallback to single source; new
params uwb_weight + uwb_timeout
• person_follower_params.yaml — uwb_weight: 0.7, uwb_timeout: 1.0s
• test_person_follower.py — 7 new TestFuseTargets cases; total 60 pass
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
sl-jetson
a00dbe6429