dorsal/arxiv
View SchemaProjective geometry for human motion, with an application to injury risk
| Authors | Henri Laurie, Rudi Penne |
|---|---|
| Categories | |
| ArXiv ID | q-bio/0406024 |
| URL | https://arxiv.org/abs/q-bio/0406024 |
Abstract
We give an exposition of Plucker vectors for a system of joint axes in projective 3-space. We use Plucker vectors to analyse dependencies among joint axes, and in particular show that two rotational joints rigidly joined by a bar and each with 3 degrees of freedom always forms a 5-dimensional system. We introduce the concept of reduced redundancy in a dependent set of projective Lines, and argue that reduced redundancy in the axes of a body position increases injury risk. We apply this to a simple two-joint model of bowling in cricket, and show by analysis of some experimental data that reduced redundancy around ball release is observed in some cases.
{
"annotation_id": "f6ff07b2-6fd2-4a85-8645-8c4fd8c402ce",
"date_created": "2026-03-02T18:01:31.674000Z",
"date_modified": "2026-03-02T18:01:31.674000Z",
"file_hash": "0fa6629866648d8b9e481c2ae532b729c24d9b78d434c3d6ebe3fb527e225e97",
"private": false,
"record": {
"abstract": "We give an exposition of Plucker vectors for a system of joint axes in\nprojective 3-space. We use Plucker vectors to analyse dependencies among joint\naxes, and in particular show that two rotational joints rigidly joined by a bar\nand each with 3 degrees of freedom always forms a 5-dimensional system. We\nintroduce the concept of reduced redundancy in a dependent set of projective\nLines, and argue that reduced redundancy in the axes of a body position\nincreases injury risk. We apply this to a simple two-joint model of bowling in\ncricket, and show by analysis of some experimental data that reduced redundancy\naround ball release is observed in some cases.",
"arxiv_id": "q-bio/0406024",
"authors": [
"Henri Laurie",
"Rudi Penne"
],
"categories": [
"q-bio.QM",
"q-bio.OT"
],
"title": "Projective geometry for human motion, with an application to injury risk",
"url": "https://arxiv.org/abs/q-bio/0406024"
},
"schema_id": "dorsal/arxiv",
"source": {
"execution_id": "f1424d44-f54a-40da-818d-bf90e93c7846",
"id": "arXiv Dataset IDs",
"type": "Model",
"variant": "snapshot-2026-03-01",
"version": "0.1.0"
},
"user_id": 1000002
}