System development of image based 3d surface reconstruction

Dissertant

al-Jaf, Ahmad Abd Allah Ibrahim

Thesis advisor

Abbas, Tahsin Fadil

University

University of Technology

Faculty

-

Department

Department of Production Engineering and Metallurgy

University Country

Iraq

Degree

Ph.D.

Degree Date

2013

English Abstract

There is difficulty in reconstruction the three-dimensional engineering surfaces from two-dimensional images of the original surface.

The objective of this work is to contribute to facilitating the possibility of reconstruction of the three-dimensional sculptured surfaces by processing the two-dimensional images.

An image-based slicing technique and system for 3D sculptured surface reconstruction of a real object is proposed, developed and implemented.

The developed system is relatively low cost and easy to implement and has been tested on five different sculptured surfaces.

The test surface is placed in a cubical liquid container filled with a dark liquid (dark blue soluble ink ) and the intersections between the liquid level and the real sample are generated by raising the movable base in step by step manner , and for each step an image has been captured, the image is taken at every up word step using a single digital camera that is positioned at a convenient height and perpendicular to the center of the movable base.

The depth of each cross section can be directly obtained for each of the captured image Images were processed using MATLAB version 7.12.0635 (R2011a) package where they converted into binary data to find the edges and then redraw these edges and assemble them using the AutoCAD 2013 after giving elevation value for each slice and then these slices connection are rendered to reconstruct the sculptured surface.

It’s found through reconstructing the 3D engineering sculptured surfaces that the general trend largely corresponds to the shapes of the original models for all five tested samples.

To increase the accuracy of the correspondence between the surfaces that were reconstructed and the original surfaces of the samples, three methods have been used, a spline, nearest interpolation and least square fitting after the division of the surface to grid of 50x50 then these surfaces reconstructed.

It has been found that all the mathematical interpolating and fitting greatly enhance the final shape but the least square fitting gives greater accuracy than other two methods.

The enhanced data using least square fitting of one model has been manipulated to generate the toolpath and one sculptured surface is machined using CNC milling machine.

Main Subjects

Materials Science , Minerals

Topics

• Digital electronics

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-412994