{
  "id": 583452,
  "title": "Clarification: Are Sensor Positions (ToF-1~5, Thermo-1~5) Geometrically Identical for Left- and Right-Handed Subjects?",
  "url": "/competitions/cmi-detect-behavior-with-sensor-data/discussion/583452",
  "author_name": "",
  "post_date": "2025-06-07T00:49:46.301077600Z",
  "votes": 19,
  "comment_count": 2,
  "views": 0,
  "content": "<p>Dear Hosts,<br>\n<a href=\"https://www.kaggle.com/floriancmi\" target=\"_blank\">@floriancmi</a></p>\n<p>I understand that the sensors are always attached to the dominant (i.e., handed) arm.  <br>\nHowever, I would like to clarify whether the geometric arrangement of the sensors (TOF-1~5, Thermo-1~5) is identical between left- and right-handed subjects.</p>\n<p>In other words:</p>\n<ol>\n<li>Are the sensors (e.g., TOF[1~5], Thermo[1~5]) physically arranged in <strong>exactly the same configuration</strong>, or are they <strong>mirrored</strong> (i.e., flipped across the midline of the body)?</li>\n<li>Additionally, is the <strong>internal arrangement of chips (e.g., TOF[1~5][v0~v63]) on each sensor board</strong> also mirrored between left- and right-handed configurations?</li>\n</ol>\n<p>Thank you!</p>\n<p><img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F4910466%2Fd0de65dfcd1da95458d46eea5c5c4dd9%2Fsensor_picture.png?generation=1749257242026631&amp;alt=media\" alt=\"\"></p>\n<p><img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F4910466%2F5c88abef25a8edb0726ed6917f992d4e%2Finbox_26856272_4efb2102b438d83fb3a65e135acaa14b_Helios_ToF_Grid_Fig.jpg?generation=1749257797051116&amp;alt=media\" alt=\"\"></p>",
  "messages": [
    {
      "id": "3218945",
      "postDate": "06/07/2025 00:49:46",
      "content": "<p>Dear Hosts,<br>\n<a href=\"https://www.kaggle.com/floriancmi\" target=\"_blank\">@floriancmi</a></p>\n<p>I understand that the sensors are always attached to the dominant (i.e., handed) arm.  <br>\nHowever, I would like to clarify whether the geometric arrangement of the sensors (TOF-1~5, Thermo-1~5) is identical between left- and right-handed subjects.</p>\n<p>In other words:</p>\n<ol>\n<li>Are the sensors (e.g., TOF[1~5], Thermo[1~5]) physically arranged in <strong>exactly the same configuration</strong>, or are they <strong>mirrored</strong> (i.e., flipped across the midline of the body)?</li>\n<li>Additionally, is the <strong>internal arrangement of chips (e.g., TOF[1~5][v0~v63]) on each sensor board</strong> also mirrored between left- and right-handed configurations?</li>\n</ol>\n<p>Thank you!</p>\n<p><img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F4910466%2Fd0de65dfcd1da95458d46eea5c5c4dd9%2Fsensor_picture.png?generation=1749257242026631&amp;alt=media\" alt=\"\"></p>\n<p><img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F4910466%2F5c88abef25a8edb0726ed6917f992d4e%2Finbox_26856272_4efb2102b438d83fb3a65e135acaa14b_Helios_ToF_Grid_Fig.jpg?generation=1749257797051116&amp;alt=media\" alt=\"\"></p>",
      "rawMarkdown": "Dear Hosts,\n@floriancmi\n\nI understand that the sensors are always attached to the dominant (i.e., handed) arm.  \nHowever, I would like to clarify whether the geometric arrangement of the sensors (TOF-1~5, Thermo-1~5) is identical between left- and right-handed subjects.\n\nIn other words:\n\n1. Are the sensors (e.g., TOF[1~5], Thermo[1~5]) physically arranged in **exactly the same configuration**, or are they **mirrored** (i.e., flipped across the midline of the body)?\n2. Additionally, is the **internal arrangement of chips (e.g., TOF[1~5][v0~v63]) on each sensor board** also mirrored between left- and right-handed configurations?\n\n\nThank you!\n\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F4910466%2Fd0de65dfcd1da95458d46eea5c5c4dd9%2Fsensor_picture.png?generation=1749257242026631&alt=media)\n\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F4910466%2F5c88abef25a8edb0726ed6917f992d4e%2Finbox_26856272_4efb2102b438d83fb3a65e135acaa14b_Helios_ToF_Grid_Fig.jpg?generation=1749257797051116&alt=media)",
      "votes": null
    },
    {
      "id": "3218979",
      "postDate": "06/07/2025 02:22:50",
      "content": "<p>The datasheet does not seem to mention the difference between left and right hands. However, it should be noted that the given data differs from that in the datasheet by a transformation of a 180° rotation about the horizontal axis.</p>\n<p><img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F8060745%2F0c15c2939d9da74c3f1fd2f4835ca9a3%2F36020250607102205474.jpg?generation=1749262947739440&amp;alt=media\" alt=\"\"></p>",
      "rawMarkdown": "The datasheet does not seem to mention the difference between left and right hands. However, it should be noted that the given data differs from that in the datasheet by a transformation of a 180° rotation about the horizontal axis.\n\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F8060745%2F0c15c2939d9da74c3f1fd2f4835ca9a3%2F36020250607102205474.jpg?generation=1749262947739440&alt=media)",
      "votes": null
    },
    {
      "id": "3220180",
      "postDate": "06/09/2025 00:54:01",
      "content": "<p>Great find. I went to look myself and under <a href=\"https://fcon_1000.projects.nitrc.org/indi/cmi_healthy_brain_network/Competitions/Helios2025/Time_of_Flight_Sensor.pdf\" target=\"_blank\">Section 7.1.3</a> on the following page, they go on to explain that the sensor flips the captured image both horizontally and vertically. As a result, would you say we should only be flipping the ToF data (as provided by CMI) along the horizontal axis?<br>\n<img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F8509053%2Fcb6815999650ccf16d6db30b41cebb09%2Fflip.png?generation=1749430176507082&amp;alt=media\" alt=\"Flipping Sensor Data\"></p>",
      "rawMarkdown": "Great find. I went to look myself and under [Section 7.1.3](https://fcon_1000.projects.nitrc.org/indi/cmi_healthy_brain_network/Competitions/Helios2025/Time_of_Flight_Sensor.pdf) on the following page, they go on to explain that the sensor flips the captured image both horizontally and vertically. As a result, would you say we should only be flipping the ToF data (as provided by CMI) along the horizontal axis?\n![Flipping Sensor Data](https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F8509053%2Fcb6815999650ccf16d6db30b41cebb09%2Fflip.png?generation=1749430176507082&alt=media)",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 3218979,
      "author_name": "act18l",
      "author_url": "",
      "post_date": "06/07/2025 02:22:50",
      "content": "<p>The datasheet does not seem to mention the difference between left and right hands. However, it should be noted that the given data differs from that in the datasheet by a transformation of a 180° rotation about the horizontal axis.</p>\n<p><img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F8060745%2F0c15c2939d9da74c3f1fd2f4835ca9a3%2F36020250607102205474.jpg?generation=1749262947739440&amp;alt=media\" alt=\"\"></p>",
      "votes": null,
      "replies": [
        {
          "id": 3220180,
          "author_name": "petermoorhouse",
          "author_url": "",
          "post_date": "06/09/2025 00:54:01",
          "content": "<p>Great find. I went to look myself and under <a href=\"https://fcon_1000.projects.nitrc.org/indi/cmi_healthy_brain_network/Competitions/Helios2025/Time_of_Flight_Sensor.pdf\" target=\"_blank\">Section 7.1.3</a> on the following page, they go on to explain that the sensor flips the captured image both horizontally and vertically. As a result, would you say we should only be flipping the ToF data (as provided by CMI) along the horizontal axis?<br>\n<img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F8509053%2Fcb6815999650ccf16d6db30b41cebb09%2Fflip.png?generation=1749430176507082&amp;alt=media\" alt=\"Flipping Sensor Data\"></p>",
          "votes": null,
          "replies": []
        }
      ]
    }
  ],
  "raw_markdown_by_id": {
    "3218945": "Dear Hosts,\n@floriancmi\n\nI understand that the sensors are always attached to the dominant (i.e., handed) arm.  \nHowever, I would like to clarify whether the geometric arrangement of the sensors (TOF-1~5, Thermo-1~5) is identical between left- and right-handed subjects.\n\nIn other words:\n\n1. Are the sensors (e.g., TOF[1~5], Thermo[1~5]) physically arranged in **exactly the same configuration**, or are they **mirrored** (i.e., flipped across the midline of the body)?\n2. Additionally, is the **internal arrangement of chips (e.g., TOF[1~5][v0~v63]) on each sensor board** also mirrored between left- and right-handed configurations?\n\n\nThank you!\n\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F4910466%2Fd0de65dfcd1da95458d46eea5c5c4dd9%2Fsensor_picture.png?generation=1749257242026631&alt=media)\n\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F4910466%2F5c88abef25a8edb0726ed6917f992d4e%2Finbox_26856272_4efb2102b438d83fb3a65e135acaa14b_Helios_ToF_Grid_Fig.jpg?generation=1749257797051116&alt=media)",
    "3218979": "The datasheet does not seem to mention the difference between left and right hands. However, it should be noted that the given data differs from that in the datasheet by a transformation of a 180° rotation about the horizontal axis.\n\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F8060745%2F0c15c2939d9da74c3f1fd2f4835ca9a3%2F36020250607102205474.jpg?generation=1749262947739440&alt=media)",
    "3220180": "Great find. I went to look myself and under [Section 7.1.3](https://fcon_1000.projects.nitrc.org/indi/cmi_healthy_brain_network/Competitions/Helios2025/Time_of_Flight_Sensor.pdf) on the following page, they go on to explain that the sensor flips the captured image both horizontally and vertically. As a result, would you say we should only be flipping the ToF data (as provided by CMI) along the horizontal axis?\n![Flipping Sensor Data](https://www.googleapis.com/download/storage/v1/b/kaggle-forum-message-attachments/o/inbox%2F8509053%2Fcb6815999650ccf16d6db30b41cebb09%2Fflip.png?generation=1749430176507082&alt=media)"
  },
  "source": "meta"
}