The evaluation and improvement of 3D shape acquisition techniques

Three-dimensional (3D) shape acquisition has many important applications in different fields. Engineering, medicine, architecture, and entertainment are some examples where it is used.; This research is focused on the evaluation and development of a feasible and economic technique for 3D data acquirement. Nowadays different methods are used for 3D shape acquisition. These methods can be divided into the contact and non-contact approaches. The most popular contact devices are the joined arms and the coordinate measure machines (CMMs). The most common non-contact products are the laser scanners. These methods are high accurate and easy to use, but they are expensive.; Other methods used for 3D acquisition involves projected light into the object's surface and digital cameras for capturing the image. These methods are characterized by the low cost since only a projected light and a digital camera are needed.; Three objectives are proposed for this work. The first one is the evaluation of existing 3D acquisition methods. The second one is the implementation of a new approach to obtain confident 3D data at a low cost. And the last one deals with the comparison between the different approaches. To achieve the goals two methods are proposed based on image processing techniques. The methods are the shape from shading method (SFS) and the structured light approach.; An improved SFS approach is implemented based on one of the studied methods. A new structured light method is developed. In this method a grid with separation between lines of 6 pixels and 1 pixel thickness of line is projected to the object. A digital camera that captures the distortion of the grid takes the image. 3D data is then collected from the distortion of the grid. The 3D data is then recovered based on the distortion of the grid on the object.