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Updated: Jun 26, 2025
06:34
Finite Element Modeling for the Simulation of the Quasi-Static Compression of Corrugated Tapered Tubes
Published on: January 6, 2023
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The inner tube effect
Ian M Thornton1, Sunčica Zdravković2,3, Dejan Todorović3
1Department of Cognitive Science, Faculty of Media and Knowledge Sciences, University of Malta, Msida, Malta.
I-Perception
|May 13, 2024
Summary
A novel size illusion causes targets to appear to shrink or grow within a narrow tube, depending on contrast. This visual perception effect, observed in static and dynamic displays, is explored with an interactive demo.
Area of Science:
- Visual perception
- Psychophysics
- Optical illusions
Background:
- The "rocking line" illusion (RLI) demonstrates dynamic visual effects.
- Previous research has explored various size and contrast-dependent visual phenomena.
Purpose of the Study:
- To describe a new size illusion.
- To investigate the influence of contrast and display scale on this illusion.
- To provide an interactive tool for exploring the illusion's parameters.
Main Methods:
- Observation of the size illusion in static and dynamic visual displays.
- Analysis of the relationship between contrast steps and perceived size change.
- Development of an online, interactive demo to explore the illusion's parameter space.
Main Results:
- A novel size illusion was identified where targets appear to change size within a narrow tube.
- The direction of perceived size change (shrinking or growing) is determined by the contrast step between display elements.
- The overall scale of the display influences the magnitude of the size illusion.
Conclusions:
- The contrast step between display elements is a critical factor in this novel size illusion.
- The illusion is observable in both dynamic and static visual contexts.
- The findings contribute to our understanding of visual perception and size constancy mechanisms.
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