Pictures of our low cost consumer-oriented range finder in action References R. B. Fisher, A. P. Ashbrook, C. Robertson, and N. Werghi. Reverse Engineering of CAD models from objects Modern manufacturers use a computer CAD model of a part to generate instructions as to how the part can be made. Data collected from 3D range finders contain no information about the underneath of the object, the part in the shadow of the laser. These images have to be registered and merged in order to collect complete information about the object. Our current work centres on generating a more accurate and coherent model suitable for industrial use.
All solid objects have geometric constraints which can be exploited by the modelling process.
For example, surfaces meet other surfaces, and do not cut through each other. The models needed by industry are generally designed with more rigid feature relationships. The consideration of these relationships is actually necessary because some attributes of the object would have no sense if the object modelling scheme did not take into account these constraints. Exploiting these relationships is useful for reducing the effects of registration errors and mis-calibration, thus improving the accuracy of the estimated part features' parameters and consequently the quality of the modelling. Naoufel Wergi is using classical optimisation techniques to incorporate this extra knowledge into the modelling process.