SYDEM: A New Approach to Computer-Aided Design of Assemblies and Assemblability Testing

At the end of the manufacturing process, engineers need to know if a manufactured part fits its computer-aided design (CAD) model and how is the amplitude of inherent variation of manufacturing process. Non-rigid parts, at free state condition, may have a significant different form than their CAD model due to gravity loads; residual stresses induced distortion and/or assembly load. Today, a complicated and expensive specialized fixture is needed to conform these parts. To tackle the above challenges, we present in this paper a new approach for metrology of fixtureless non-rigid parts. This approach combines the curvature properties of manufactured parts with the extreme value statistic test as identification method to distinguish profile deviation due to the manufacturing process from part’s deformation due to the flexibility of the part and to determine whether the tolerance fits the CAD model or no. This approach is tested on simulated typical industrial sheet metal giving satisfying results in terms of percentage of errors in defect area and in peak profile deviation estimated.

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Presentation of CIBAO: A New Approach for Integrated Computer-Aided Design Systems for the Building Activities

1989 2nd European Conference on Architecture ◽

10.1007/978-94-017-0556-1_148 ◽

1990 ◽

pp. 507-510

Author(s):

Anne-Marie Dubois

Keyword(s):

Computer Aided Design ◽

New Approach ◽

Computer Aided ◽

Design Systems ◽

Building Activities ◽

Aided Design

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PROSTHETIC EAR RECONSTRUCTION APPLYING COMPUTER TOMOGRAPHIC (CT) DATA AND ADDITIVE MANUFACTURING TECHNOLOGIES

Jurnal Teknologi ◽

10.11113/jt.v76.5716 ◽

2015 ◽

Vol 76 (7) ◽

Author(s):

Nor Azura Mohamed ◽

Zainul Ahmad Rajion

Keyword(s):

Additive Manufacturing ◽

Medical Imaging ◽

Computer Aided Design ◽

Physical Models ◽

Ear Reconstruction ◽

New Approach ◽

Imaging Technology ◽

Wax Pattern ◽

Computer Aided ◽

Aided Design

The treatment of auricle defect can be by surgical or prosthetic ear rehabilitation depending on the condition. Current practice by surgeon for prosthetic ear rehabilitation require patient to go for osseointegrated craniofacial implant surgery for retention of the prosthetic ear. Impression technique play a vital role in accurate reproduction of affected and unaffected ears, orientation of the ear during wax try in and fabrication of ear prostheses. Traditionally, the wax pattern was created from the impression taken from patient and the final prosthesis is processed with silicone material. This conventional method has always been time consuming, massive work and caused discomfort to patient. Moreover the accuracy of the final prosthetic sometimes was not satisfied. Improvement in medical imaging technology whereby data from computerized tomography (CT) in 2D format can be converting to 3 dimensional images gave tremendous view for surgeon to visualize the result. A new and impressive advance in the development of additive manufacturing technology is now being able to be applied in medical field. The widespread use of computer-aided design (CAD) combine with computer aided manufacturing (CAM) produced the momentum and desire to translate the 3-D images into physical models. Studies and research have indicated the viability of using medical imaging technology, computer aided design (CAD) and additive manufacturing techniques in prosthetics. This paper proposed a novel method of fabricating the prosthetic ear applying mirror image technique to reconstruct the missing ear, and then fabricate the 3D model of the prosthetic ear using Stereolitography (SLA) technology that will become the master mold to produce the final prosthetic ear. This method eliminates the traditional wax pattern procedure. A clinical study is done onto a patient in HUSM and comparison is made between traditional method vs new approach using computer aided technology. Result showed that there is significant different between traditional and new approach design. The new method also shows time reduction during design and fabrication stage.

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