Research On 3d Modeling Of UAV Tilt Photography And Accuracy Of Large Scale Topographic Map Drawing

In recent years,a new technology called unmanned aerial vehicle(UAV)tilt photogrammetry has been developed in the field of Surveying and mapping.It can quickly obtain the multi view image of the target object in a short time.With the development of computer technology,3D modeling technology is becoming more and more mature.Combining the UAV tilt photogrammetry technology with 3D modeling technology,the 3D model produced has the characteristics of high accuracy,strong authenticity,clear texture,etc.,and has been widely used in smart city,digital city,medical and traditional architecture fields.The role of three-dimensional model in the field of Surveying and mapping can not be underestimated.There are many problems in traditional topographic mapping,such as time-consuming,low current,low efficiency,high cost and so on.The 3D model based on EPS platform can effectively improve the difficulty of topographic map drawing and provide new technology and method for topographic map drawing.Based on the actual project,taking Taoshan village,Yongxin County,Ji'an City as an example,this paper proves that the accuracy of topographic map based on EPS platform can meet the requirements of large-scale topographic map.The following is the main research content of this paper:1.Using the Pegasus D200 aerial survey system to obtain image data,building a true 3D model based on the context capture platform,in order to improve the integrity and precision of the model,using the Geomagic studio and meshixer software to repair the model cavity;2.Build 3D model based on context capture software,and analyze the precision of 3D model from three aspects of model precision,model space precision and model reconstruction precision according to corresponding reference standards;3.Study the influence of five drawing methods on the drawing accuracy of three types of houses,summarize the best drawing methods of houses,then draw large-scale topographic map based on EPS platform,and analyze whether the accuracy of the drawn topographic map meets the requirements of the mapping accuracy from five aspects of plane,elevation,length,angle and area.The results show that the texture of the 3D model is clear,the structure is relatively complete,and the authenticity is strong;the plane and elevation accuracy of the control points and inspection points after the three-dimensional model space solution can meet the accuracy requirements of 1:500 scale;the plane mean square error of the reconstructed 3D model is 0.026 m,and the height mean square error is 0.019 m,that is to say,the plane and elevation accuracy meet the accuracy specifications of 1:500 scale;from the above three-dimensional model space three-dimensional model space solution,the plane and elevation accuracy can meet the accuracy requirements of 1:500 scale The accuracy analysis results show that the overall accuracy of the three-dimensional model is high,which can be used for subsequent production of large-scale topographic map.Through the analysis of the influence of the drawing method on the drawing accuracy of the house,the best drawing method of the house is summarized.In order to further verify the drawing accuracy of the large-scale topographic map based on the three-dimensional model and EPS platform,the drawing accuracy of the topographic map is analyzed from five aspects of plane,elevation,length,angle and area.The research results show that the accuracy of large-scale topographic map based on EPS platform can meet the requirement of 1:500 topographic map from point to line and then to surface,from local to whole.That is to say,it is a new method with time-saving,low cost,high efficiency and guaranteed accuracy to use 3D model to draw large-scale topographic map based on EPS platform.