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It is quite difficult to quickly design the special inserts or shoes for the particular patient who faces the problem about foot’s shape. Well-mould designing can make the geometric shapes of the inserts to be properly fitted to the feet, as the results, the pains can be relieved where the patient can perform the daily activities with more comfortable. To quickly copy near-net shape of the virtual model from the master part, the integrating between reverse engineering and slush casting has been applied where the Automated Selective Acquisition System (ASAS) has been applied in this research as the alternative reflective-scanning method to obtain an organized data set without applying any data reduction processes. For assisting the ASAS technique to quickly acquire the non-rigid part as feet, generating the solid feet by slush casting technique has been firstly performed where the various materials have been studied under the criteria of economical-based impression and non-skin allergic problems.

Reverse engineering (RE) has been used closely with rapid prototyping (RP) for fabricating one object from another. Existing RE–RP integrations all begin with the data acquisition of the entire surface of an object. This large point cloud data contains redundancy that must be reduced to avoid unnecessary difficulty in a subsequent surface reconstruction step. Presented in this paper is an alternative approach for direct RE–RP integration. Rather than performing data reduction after capturing the data of an entire object, data are acquired selectively and locally layer by layer. An image-processing algorithm has been developed for recommending the scanning positions based on the part complexity to minimise the number of scans. The result of each scan is contour data points, which can be directly used to generate commands for fabricating a prototype. The implementation of this selective data acquisition approach with a non-contact measuring device is also presented and discussed.

Build time and accuracy are two contradicting issues that have been a major concern in rapid prototyping, and have led to the development of many slicing approaches including those applying adaptive slicing, direct slicing, and adaptive direct slicing concepts. Presented in this paper is an approach for adaptive direct slicing that applies image processing technique to determine appropriate thickness for each sliced layer and to recommend slicing positions on a 3D CAD model. Two orthogonal views of a model are captured and converted to be edge images before being analyzed, and based on the surface complexity on the two edge images, slicing positions are recommended. These positions are passed to the CAD software for slicing activities. This adaptive direct slicing approach has been implemented on LabVIEW platform and compared with uniform direct slicing approach and uniform cusp height approach. The results show that this slicing approach improved slicing performance by reducing the number of layer which has a direct impact on build time while maintaining surface quality at the same level as the thin uniform direct slicing. Since its inputs are the images of a CAD model instead of the model itself, this adaptive direct slicing supports any CAD software.

The main objectives of the proposed research are identifying, and analyzing some parameters required in scanning processes (i.e., 3D Laser scanner and ASAS). The scanning experiments will be planed and raised in sequences for identifying the appropriate conditions for saving time and cost. The expected results will be used as the guidelines for assisting the design engineer to select the proper methods and applications for enhancing the quality of 3D CAD model which may be used as the input for the subsequence process. Four main issues: preparation process, data analysis, cost for scanning, and results (i.e., 3D model) obtained from two scanning techniques will be presented and discussed.

Selective data acquisition has been researched recently as an alternative for direct interface reverse engineering (RE) with rapid prototyping (RP). Rather than performing data reduction after capturing data of an entire object, data are acquired selectively and locally layer by layer according to the analysis from the image of the object. The result of each scan is contour data points, which can be directly used to generate commands for fabricating a prototype. The concept of fringe projection is presented in this paper as a tool for recommending scanning position in selective data acquisition. A single band of bright light is projected horizontally onto the object and the image of the projected band is captured and analyzed instead of the image of the object. The study shows promising results that encourage further investigation such that adaptive reverse engineering system for direct interface with rapid prototyping (RP) can be improved.