Volume Estimation Of Curved Surfaces Using Structured Lighting And Their Similarity Measure
| dc.contributor.author | Abd Elmagid Elnaggar, Ahmed Mohamed | |
| dc.date.accessioned | 2016-09-06T07:42:52Z | |
| dc.date.available | 2016-09-06T07:42:52Z | |
| dc.date.issued | 2006-07 | |
| dc.description.abstract | This thesis presents the investigation of a non-contact method called structured lighting to determine volumes of smooth surfaces. This method uses a camera that captures a deformed pattern of light projected upon a surface. The system was verified using objects having a smooth surface. Firstly, a simulation study was carried out to determine a suitable method to determine the volume. A suitable method was found by integration of a fitted curve across coordinate points and multiplied by its depth along xdirection. The effect of different fringe pitches on volume calculation was studied. Secondly, an experiment was carried out to determine the volume of six different spherical caps. A projector was developed to project a collimated fringe pattern. A digital camera was calibrated to convert the pixel values into millimetres. The error in volume of 26 measurements was found to be less than 8.52%. A segmentation method was developed to extract the surface from the background. The segmentation method consists of three steps: (i) a triangular mesh is generated for the known surface points, (ii) the area of each triangle is calculated and (iii) the standard deviation of triangle areas that surround each surface point is calculated. All surface points that have similar standard deviation value are segmented into one patch. Finally, the shape similarity among the measured 3-0 shape is calculated. Each 3-0 model was brought into its canonical position to ensure its rotation and translation invariance. At this position, a set of features is extracted from the 3-0 model and the similarity between all models are measured. This set of features is the core length of the bounding box. The new features show better accuracy (43.75%) in sir,;!arity measure when applied to shapes with smaller height and diameter as compared to the slightly larger shapes. The work of this thesis can be used to develop a non-invasive system to measure skin tumours. | en_US |
| dc.identifier.uri | http://hdl.handle.net/123456789/2451 | |
| dc.subject | Mechanical Engineering | en_US |
| dc.subject | Similarity Measure | en_US |
| dc.title | Volume Estimation Of Curved Surfaces Using Structured Lighting And Their Similarity Measure | en_US |
| dc.type | Thesis | en_US |