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    "story_id": "mp-2026-09-10-016",
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    "edition_id": "mp-2026-09-10-morning-0063",
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    "position": 18,
    "story_type": "ticker",
    "section": "robotics",
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    "headline": "A Quadruped Learned to Hold Its Attitude Underwater",
    "slug": "a-quadruped-learned-to-hold-its-attitude-underwater",
    "dek": "Custom sealed motors and an SO(3) controller tracked roll, pitch and yaw in a water-tank experiment.",
    "summary": "Custom sealed motors and an SO(3) controller tracked roll, pitch and yaw in a water-tank experiment.",
    "body_text": "The reproducible robot uses machined polymer housings, off-the-shelf O-rings and dynamic shaft seals. A simplified drag model informs closed-loop orientation control for amphibious inspection and monitoring research.",
    "why_it_matters": "Custom sealed motors and an SO(3) controller tracked roll, pitch and yaw in a water-tank experiment.",
    "limitations": [],
    "importance": 7,
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    "first_published_at": "2026-09-10T09:00:00.000-04:00",
    "modified_at": "2026-09-10T09:00:00.000-04:00",
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        "text": "Custom sealed motors and an SO(3) controller tracked roll, pitch and yaw in a water-tank experiment.",
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    "source_ids": [
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    "tags": [
      "underwater robots",
      "quadrupeds",
      "attitude control"
    ],
    "image_url": null,
    "corrections": []
  },
  "sources": [
    {
      "source_id": "source-2026-09-10-018",
      "title": "arXiv preprint 2609.09217",
      "publisher": "arXiv",
      "url": "https://arxiv.org/abs/2609.09217",
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      "source_type": "primary_research",
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      "published_at": "2026-09-05T20:00:00.000-04:00",
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  "publisher": {
    "name": "The Machine Press",
    "url": "https://themachinepress.com",
    "description": "A daily newspaper for the age of artificial intelligence."
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  "cite_this_report": {
    "title": "A Quadruped Learned to Hold Its Attitude Underwater",
    "publisher": "The Machine Press",
    "published_at": "2026-09-10T09:00:00.000-04:00",
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