---
title: "A New Method of 3-D Motion Analysis Using a Concept of Projective Geometry"
authors:
  - "Tadahiro Kitahashi"
  - "Hiroyuki Endo"
doi: ""
url: "https://ijcai.org/proceedings/1985/181"
pdf: "https://ijcai.org/proceedings/1985/0181.pdf"
venue: "Proceedings of the Ninth International Joint Conference on Artificial Intelligence"
year: 1985
pages: "902-903"
track: "Perception"
keywords:
---

# A New Method of 3-D Motion Analysis Using a Concept of Projective Geometry

Tadahiro Kitahashi, Hiroyuki Endo

*Proceedings of the Ninth International Joint Conference on Artificial Intelligence*, pages 902-903.

## Abstract

This paper describe s a method of interpreting three dimensional motion of an object by making use of rigidity assurnption and orientation of its edge . We employ a vanishing point to determine the o rient a tion. We propese a new idea of using cross ratio, i.e . one of the mo st fundament a l concepts in pr o jective ge o metry to find a vanish ing point of a line. This a ll ows t o calculate the l oca ti o n of a van i s hing point with a known seq uence of p o int s on it withovc another parallel line required by the conventional meth od .