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Published on: October 20, 2023
Shape change along geodesics with application to cleft lip surgery
Julian J Faraway1, Carroll-Ann Trotman
1University of Bath, UK.
Summary
Human motion can be represented as curves in shape space. This study shows these curves approximate geodesics, simplifying motion analysis and enabling prediction of animated facial movements.
Area of Science:
- Biomechanical analysis
- Computer graphics
- Medical imaging
Background:
- Continuous shape change is mathematically modeled as curves within a shape space.
- Assessing the deviation of these motion curves from geodesic paths is crucial for accurate analysis.
- Human motion data, particularly facial movements, requires sophisticated methods for independent analysis of dynamic and static components.
Purpose of the Study:
- To introduce a method for evaluating how closely motion curves in shape space approximate geodesics.
- To analyze human motion databases, including facial motion data from individuals with cleft lip or palate, to understand shape changes.
- To develop inferential methods for assessing motion changes and to discuss the creation of predicted animated motions.
Main Methods:
- Representing continuous shape change as curves in shape space.
- Developing and applying a method to check the proximity of these curves to geodesics.
- Analyzing large databases of human motion, including specialized facial motion data.
- Utilizing inferential statistics to assess motion alterations.
- Exploring techniques for generating predicted animated motion sequences.
Main Results:
- Three large human motion databases were found to be well-approximated by geodesics.
- Motions can be effectively represented by two key shapes and a rate of progression along the geodesic path.
- Facial motion data from subjects with cleft lip/palate was analyzed, separating dynamic motion from static shape.
- Inferential methods for assessing motion changes were successfully applied.
Conclusions:
- Geodesic approximation provides a robust framework for analyzing and representing continuous shape changes in human motion.
- The developed methods allow for independent analysis of dynamic facial motion and static shape, particularly relevant for clinical studies.
- This approach facilitates the prediction and generation of animated motions, with potential applications in medical visualization and rehabilitation.
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