Key Technologies For 3D Model Construction Using Camera And 2D Laser Range Finder

3D construction technology based on the information collection by camera and laser range finder has attracted great attention all along. And this technology has been widely used in many fields such as the environment sensing using mobile robots, industry manufacture, virtual reality, and augmented reality. By detailed analysis of 3D construction technology based on the different measure method, we chose the 2D laser range finder with invisible stripe and the camera to establish the hardware system, because they have more suitable price and higher adaptability for the environment than other sensors of the 3D measurement. We had also established the software system to control the sensors, to obtain the information, and process the information. Using the measurement of the system, we focused on the methods study and practical application of the image feature extraction, the image matching, the system calibration and the color 3D modeling respectively.Using the camera and the 2D laser range finder, our object is to study the key technologies of 3D model construction in theory, and to establish a 3D color reconstruction system to construct the 3D color model of the indoor scene in practice.The main creativities of this paper are as follows:1. A line extraction algorithm is presented based on the fuzzy threshold. The algorithm can effectively extract the line from the image with the distortion and the complex background. The effectiveness of the algorithm was proved in the application of the colunm detection and the distance estimation along the railway.2. A corner matching algorithm is presented based on the uniqueness of Delaunay triangulated grid and the similarity of the grids for two matching corner sets in the same scene. Experiments on real images demonstrated the good performance of our method, and it was not affected by scale change, less affected by rotation and translation to some extent.3. Based on the main features analysis for the 2D laser range finder calibration, we designed a right-angled triangular checkerboard using the line feature. The efficiency of the checkerboard was demonstrated in the calibration between the laser range finder and the camera. And the calibration between the 2D laser range finder and the pan-tilt platform also proved the checkerboard's efficiency.4. An algorithm for the extrinsic parameter calibration of the camera and the 2D laser range finder with invisible stripe is presented which effectively solve the data correspondence problem of different sensors. Through the experiment of the simulated data and the real data captured by our system, it was proved that our method could more precisely calibrate the sensors and more effectively fuse the data than the existed calibration methods.5. For the extrinsic parameter calibration of the pan-tilt platform and the 2D laser range finder with invisible stripe, an algorithm is presented based on the colinearity, coplanarity, and orthogonality of the range information. The experimental result proved that it could effectively solve the correspondence problem of the range information with the different pan-tilt platform's rotation angle.6. An asynchronous information fusion algorithm is presented for 3D color model construction, which could solve the information fusion desynchronizing problem of high frequent range information and high resolution image in the applications. This algorithm could effectively fuse the information of different sensors and construct vivid 3D color point cloud model of indoor sense.