3D Modeling of Buildings Based on RTK and Image Processing

Abstract

High precision points on high buildings’ wall is hard to measure. The paper proposed a new way to measure buildings’ geometry shape and size accurately in a low cost and easygoing way. This system is called v-RTK (vedio-RTK) System designed by Hi-Target Group. This equipment is based on Real-Time Kinematic (RTK ) and image processing algorithm , which contains one camera , one GNSS receiver based on RTK (RTK for short), one Microsoft surface and post-processing software and hand-held. Camera and RTK is fixed together in short distance and camera’s location is calculated by RTK’s output. The accurate attitude angle and heading of camera is needed to calibrate image’s direction, which provide by an AHRS (Attitude and Heading System) embedded in RTK .Calculating the distance information of characteristic points of image from a serials of images are based on triangulation and common line equation. It lets user modeling the buildings’ geometry shape and size accurately by taking the photo walk around the building from different direction, didn’t need any control points. The paper introduced the principle of the points’ coordinate calculating detailed. The image characteristic points’ coordinate will be calculated. This part of work, we named it as Outside Work and don’t need user know too much. After that, using post-processing software process the image and coordinate, output the accurate 3D model which looks like real building. This part named Inside Work. This type of measurement is similar with aerial mapping, but cheaper and easy to use. It has other applications, such as electric power transportation equipment inspection and traffic scene reduction, we use v-RTK located the failure. Restoration of traffic accident, construction progress check, 3D residential district, and other huge constructions on ground modeling. According to tests’ results, the point’s location error in 10cm and it meets the needs of special field.