Key Engineering Materials Vols. 656-657

Abstract: For producing dense 3D reconstructed coordinates in a 360º view, comprehensive calibration of structured light measurement system is proposed to calibrate the camera, laser and turntable using planar chessboard. The camera captures images containing the chessboard placed on the turntable with laser stripe projecting onto it. Firstly, camera model is determined by using multiple views of chessboard positioned differently; secondly, laser plane is estimated with the 3D reconstructed coordinates of laser stripes viewed at various angles; finally, rotation axis is decided under the constraint of each circular motion trajectory of chessboard corners from different perspectives. Experimental results demonstrate that the proposed method is effective for estimating the parameters of camera model, laser plane and rotation axis at a high accuracy.

Abstract: Environmental monitoring plays a very important role in the activities of predicting and protecting environments and society. The activities are included of monitoring environmental parameters continuously, predicting and evaluating the effects of environments on society, warning immediately the abnormal phenomenon or pollution due to environmental changes, making data base etc. In the paper, we will present our proposal of design and implementation of a kit monitoring environmental parameters such as temperature, humidity, pH, salt percentage, water level, etc remotely through internet. Obtained data will be monitored, handled, managed, reported. The system has been used to monitor environmental parameters to evaluate the waste water in industrial zones in Hochiminh City, Vietnam.

Abstract: Mesh generation is one of the key factors affecting computational efficiency and accuracy in finite element analysis.More and more software provides modules for automatic meshes generation. Owing to the complexity and variety of the shape on a CAD model, it needs the recognition of specific features to enhance the success of meshes generation. Holes are one of the fundamental features in 3D CAD models and appear in various types of form. The aim of this study is to present a method for the recognition of different kinds of holes. The primary concept of the proposed algorithm is to detect blend faces first, and then search for holes in accordance with the loop data in the B-rep model. The procedures for the recognition of blend faces and holes are described. Several examples are also presented to demonstrate the feasibility of the proposed algorithm.