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https://github.com/ly0n/range-imaging-applications-for-dynamic-deformation-measurement

My master thesis about the measurement of surface dynamics with Time-of-Flight cameras like the Kinect 2
https://github.com/ly0n/range-imaging-applications-for-dynamic-deformation-measurement

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My master thesis about the measurement of surface dynamics with Time-of-Flight cameras like the Kinect 2

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README 

        
# Range Imaging Applications for Dynamic Deformation Measurement

Tobias Augspurger

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Thanks to all constributors at FH Aachen - Aerospace Engineering.



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![alt text](/doc/pictures/PointCloud.png)



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![alt text](/doc/pictures/Amp_dis_3D_0_7m.png)

Membrane Surface Amplitude Distribution

## Abstract



Three-dimensional Time-of-Flight (ToF) range cameras improved significantly in accuracy,

speed, price and size over the last years. By delivering the range from the scene to the

image sensor in every pixel, static and dynamic scenes can be reconstructed into a three-

dimensional model contactless from a single point of view. The observed area is illuminated

by infrared diodes and a IR CMOS camera measures the time delay of the returning light .

Out of it the range is acquired parallel with no time delay between the pixels . This offers

the potential for various close to medium range applications. One of this is the measurement

of vibrations and structural deformations under dynamic loads. In contrast to other present

measurement methods, complete surface movements can be acquired in parallel without

a movable laser beam or a complex stereo triangulation between multiple cameras . The

Kinect 2 range camera is used to show the performance of vibration measurements and to

analyze how the range images can be filtered and processed. It is the first ToF camera on

the consumer market and at the time of release the one with the highest number of pixels

(512x424 at 30 frames per seconds). It delivers 3D informations from 0.6 m to 8.0 m at a

depth resolution of 1 mm. A Laser Doppler Vibrometer is used, as high precision reference

measurement device, delivering the highest standard in deformation measurement on a

single surface point. This thesis will prove, that vibrations of a body can be reconstructed

at amplitudes of 4 mm with an accuracy below 1 mm. The performance depends on the

distance to the camera, angle of view, surface material, number of investigated pixels and

the measurement time. At the ideal distance of 1.3 m to 1.5 m, the error to the reference is

reduced down to 0.05 mm after 8 seconds of measurement at a frequency of 3 Hz. Even

the first and second harmonics are visible in the frequency domain on white paper, offering

a high reflectivity for the infrared light of the ToF measurement principle. The influence

on the accuracy of different angles to the surface normal is another topic. A vibration of

3 Hz can be reconstructed correctly in frequency up to an angle of 45 ◦ . The amplitude

is overestimated with higher angles. Since every pixel delivers a range information, the

complete video stream can be processed by a Fast-Fourier Transform to derive the dynamic

behavior of the whole field of view. The vibration can be illustrated in images, representing

the amplitude and frequency distribution in the complete field of view over a certain time span.



Thanks senfi for your latex template:

https://github.com/senfi/Abschlussarbeit-Vorlage