Development Of Surveying Design System Using Android Online Map Service

For the problems of low efficiency of control network design,difficulty in engineering surveys,and frequent updates of geographical information,full consideration was given to the trend of universal mobile phones such as smartphones and the universal map service function of Baidu maps,and development was realized with the control network design and measurement design system for industry survey and digital mapping.The system realizes the integration of control network design visualization and accuracy estimation,digitization of engineering survey work,and rapid map updating.The main research contents and results of the paper are as follows:For the problem of diversified data reading,this paper uses byte input stream method and Java regular expression to realize the coordinate extraction of three common geography files: CSV,KML,and JSON.Secondly,faced with the visual requirements for geographic data processing and result display,the paper has expanded Baidu maps' single drawing function,introduced error ellipse drawing method and radar chart drawing method.Through the actual drawing effect comparison formula method,the base drawing expansion method and the arc segment method,the formula drawing the error ellipse is the best conclusion.Thirdly,aiming at the problem of online map coordinate encryption in the country,which cannot be converted with the WGS84 coordinate,the accuracy of the coordinate deciphering method is proposed and compared with the isometric migration method,BP neural network method and grid method.The experimental results show that the accuracy of the equal displacement method highest.In addition,this paper compares the three positioning accuracy of Baidu map base station,GPS,and A-GPS in different sheltering environments,and concludes that the A-GPS positioning accuracy is the highest and meets the requirements of previous field survey work.In view of the problems existing in the current measurement work,combined with the Baidu map API map service and the above key technologies,a measurement design system was developed on the Android mobile terminal.The system functions include control network design(leveling network,wire network and GPS network),engineering survey(field reconnaissance,control point repository management and control network measurement records)and digital mapping(electronic sketches of broken step measurement and map database update).Among them,the control network design also supports the real-time mesh optimization function to ensure the accuracy of the mesh design.The control network design module aims at the low efficiency of the control network design,adopts the integration of the distribution network and the precision report output,and improves the design efficiency of the control network.Secondly,in view of the difficulties in the early survey of the project,the engineering survey module adopts map positioning and navigation functions to solve the difficult problem of field route survey and find points,and realize the digital point of note work.The module also adopts structured data storage and management methods to solve problems such as point damage,management confusion,and query difficulties in the current engineering control points.And this module can support the field control network to measure realtime record data and check the rationality of the measured data in time.Thirdly,the digital mapping module updates frequently for geographical information.In this paper,Baidu map positioning and mapping are used to realize the electronic drafting function of wild step points collection,which solves the disadvantages of hand-drawn sketches.The module also provides Baidu map POI data collection and field data collection in two ways to update the map database.