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Related Experiment Video

Updated: Jun 17, 2026

Observation of the Ciliary Movement of Choroid Plexus Epithelial Cells Ex Vivo

Observation of the Ciliary Movement of Choroid Plexus Epithelial Cells Ex Vivo

Published on: July 13, 2015

A method for calculating the circularity of movement trajectories.

M R Walters¹, R G Carson

¹Department of Human Movement, Studies University of Queensland.

Journal of Motor Behavior

|December 29, 2009

Summary

This study introduces a novel method to calculate the circularity of 2D trajectories using area moments. This technique quantifies contour shape, area, centroid, orientation, and best-fit ellipse parameters for diverse applications.

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Last Updated: Jun 17, 2026

Observation of the Ciliary Movement of Choroid Plexus Epithelial Cells Ex Vivo

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Published on: July 13, 2015

Measuring 3D In-vivo Shoulder Kinematics using Biplanar Videoradiography

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Published on: March 12, 2021

Area of Science:

Computational geometry
Image analysis
Biophysics

Background:

Quantifying the circularity of arbitrary 2D shapes is crucial for various scientific disciplines.
Existing methods may lack the flexibility to analyze complex or irregular contours.

Purpose of the Study:

To develop and present a robust method for computing the circularity of any closed two-dimensional trajectory.
To provide a comprehensive analysis of contour properties including area, centroid, and orientation.

Main Methods:

Derivation of area moments for closed contours defined by perimeter coordinates.
Application of the method to analyze two-dimensional data of arbitrary shapes.
Extraction of key geometric parameters for each contour.

Main Results:

The method successfully computes circularity for diverse 2D trajectories.
Output includes contour count, area, centroid position, orientation, and best-fit ellipse parameters.
Demonstrated applicability to kinematic trajectories, MRI data, and phase portraits.

Conclusions:

The described method offers a versatile tool for analyzing the circularity and geometric properties of 2D contours.
Its ability to handle arbitrary shapes and provide detailed outputs enhances its utility in scientific research.