Challenge: Develop an efficient tool to transfer data about buildings in apartment drawings and building plans into an object-oriented geodatabase.
There are PDF drawings available for 22,500 apartment complexes (170,000 apartment rights). Of (almost) all approximately 300,000 objects in the city (residential and non-residential), tens of thousands of building plans are available in PDF. These sometimes are vector files but usually, they are scans of paper drawings. Building geometry is available for the outer circumference of buildings (buildings), but not for apartment rights, residential objects and building parts (dwelling, basement, shop, etc.) per level. The measurement of areas (BAG / WOZ*) is done manually, where much less (administrative) data is collected and recorded than contained in the drawings.
What are we looking for?
The municipality of The Hague is looking for a technical solution based on, among other things, artificial intelligence which can convert the PDF files (semi) automatically into objects in an object-oriented geographical database. The solution must be user-friendly.
The objects to be measured are buildings, residential objects, apartment rights, building parts and division into rooms/spaces. In the geodatabase, the objects have attribute data such as function/use and 2D geometry which shows, among other things, shape, area, and location.
Finally, the solution must be extensible.
What are we not looking for?
Simple short-term solutions that cannot be further developed to be used for related purposes, such as processing new drawings, integrating with BIM (building information model) and as a 3D city model.
What is the impact?
For the BAG and WOZ, the process of measuring and coding of object characteristics changes to such an extent that more data about objects is stored in a geodatabase than with traditional measurement in a PDF drawing. The new method is reproducible and prevents double storage of drawings with measurements. For the geodatabase, the principle applies of one-time collection, multiple use. This also applies to other processes, such as the assessment of applications for an environmental permit, the BAG and enforcement of (building) legislation. In addition, it can be applied in many other municipal processes where addresses and buildings play a role.
The 2D geometry of building components that will be created is also an important building block for the construction of 3D geometry in a (nationally) integrated 3D object registration (WOZ, BAG, BGT*) and ultimately the ‘Digital Twin City’. With the Digital Twin City, the municipality of The Hague wants to connect citizens, government, and business and encourage cooperation.
What can you win?
* BAG = Base Register Addresses and Buildings; WOZ = Base Register Property Value, BGT = Base Register Large Scale Topography