Three-dimensional Study of Meteorite Ablation using a Plenoptic Camera

In this paper we present a new calibration approach for focused plenoptic cameras. We derive a new mathematical projection model of a focused plenoptic camera which considers lateral as well as depth distortion. Therefore, we derive a new depth distortion model directly from the theory of depth estimation in a focused plenoptic camera. In total the model consists of five intrinsic parameters, the parameters for radial and tangential distortion in the image plane and two new depth distortion parameters. In the proposed calibration we perform a complete bundle adjustment based on a 3D calibration target. The residual of our optimization approach is three dimensional, where the depth residual is defined by a scaled version of the inverse virtual depth difference and thus conforms well to the measured data. Our method is evaluated based on different camera setups and shows good accuracy. For a better characterization of our approach we evaluate the accuracy of virtual image points projected back to 3D space.

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METRIC CALIBRATION OF A FOCUSED PLENOPTIC CAMERA BASED ON A 3D CALIBRATION TARGET

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsannals-iii-3-449-2016 ◽

2016 ◽

Vol III-3 ◽

pp. 449-456 ◽

Cited By ~ 6

Author(s):

N. Zeller ◽

C. A. Noury ◽

F. Quint ◽

C. Teulière ◽

U. Stilla ◽

...

Keyword(s):

Three Dimensional ◽

Image Plane ◽

Depth Estimation ◽

Bundle Adjustment ◽

Optimization Approach ◽

Calibration Target ◽

Projection Model ◽

3D Space ◽

Plenoptic Camera ◽

Depth Distortion

In this paper we present a new calibration approach for focused plenoptic cameras. We derive a new mathematical projection model of a focused plenoptic camera which considers lateral as well as depth distortion. Therefore, we derive a new depth distortion model directly from the theory of depth estimation in a focused plenoptic camera. In total the model consists of five intrinsic parameters, the parameters for radial and tangential distortion in the image plane and two new depth distortion parameters. In the proposed calibration we perform a complete bundle adjustment based on a 3D calibration target. The residual of our optimization approach is three dimensional, where the depth residual is defined by a scaled version of the inverse virtual depth difference and thus conforms well to the measured data. Our method is evaluated based on different camera setups and shows good accuracy. For a better characterization of our approach we evaluate the accuracy of virtual image points projected back to 3D space.

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Three-Dimensional Particle Image Velocimetry Using a Plenoptic Camera

50th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition ◽

10.2514/6.2012-1056 ◽

2012 ◽

Cited By ~ 21

Author(s):

Kyle Lynch ◽

Tim Fahringer ◽

Brian Thurow

Keyword(s):

Particle Image Velocimetry ◽

Particle Image ◽

Three Dimensional ◽

Image Velocimetry ◽

Plenoptic Camera

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Simultaneous Particle Tracking and Temperature Measurements during Additive Manufacturing using a High-speed Spectral Plenoptic Camera

14th International Symposium on Particle Image Velocimetry ◽

10.18409/ispiv.v1i1.106 ◽

2021 ◽

Vol 1 (1) ◽

Author(s):

Dustin Kelly ◽

Ralf Fischer ◽

Ari Goldman ◽

Sarah Morris ◽

Bart Prorok ◽

...

Keyword(s):

Additive Manufacturing ◽

Particle Tracking ◽

Automotive Industry ◽

High Speed ◽

New Technology ◽

Three Dimensional ◽

Melt Pool ◽

Plenoptic Camera ◽

Metal Additive

In this work, a high-speed spectral plenoptic camera was used for three-dimensional (3D) simultaneous particle tracking and pyrometry measurements of hot spatter particles ejected during the metal additive manufacturing process. Additive manufacturing (AM) has an increasing role in the aerospace, energy, medical and automotive industry (DebRoy et al., 2018). While this new technology enables the production of highly advanced parts, research on the fundamental mechanisms governing the laser-matter interactions are an ongoing challenge because of the spatial and temporal resolution inherent to the AM process. One challenge is the characterization of spatter particles ejected from the melt pool, as these particles can be incorporated into the final part affecting the mechanical properties (Deng et al., 2020). One potential solution for simultaneously measuring velocity and temperature of the spatter particles is the spectral plenoptic camera.

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