How do you export a topographic survey of network structures (grates, catch basins, etc.) to DWG with the correct symbols, proper orientation, and accurate dimensions—without disrupting the drafters’ workflow?
I carry out field surveys of network structures (using Field Maps) (catch basins, sewer grates, manholes, etc.) using an RTK GNSS receiver with centimeter-level accuracy. The challenge is not just to locate these structures, but also to capture their true orientation and exact dimensions in space.
These data are intended to feed into technical drawings in AutoCAD. To ensure a smooth workflow for drafters, each structure must appear in the DWG with the correct symbolic block, on the right layer, at the correct size—and above all with the correct rotation, accurately reflecting its real-world orientation.
Problem:
- Unreliable manual input : Estimating an angle or a size by eye in the field introduces errors that are incompatible with a high-precision topographic survey.
Misplaced DWG block : Without the correct rotation, the CAD symbol does not reflect real-world conditions—forcing drafters to make manual corrections.
What I tried — without success :
- Point layer + separate orientation layer : I tried separating the position of the structure (point layer) from its orientation (a layer of points surveyed at the corners). The concept works in theory, but it is very cumbersome to implement in the field: it requires following a strict survey sequence between the two layers, which is error-prone and hard to maintain under real-world conditions.
Polygon layer + derived points + orientation calculation : I surveyed each structure as a polygon (3 RTK corners), then generated derived points to calculate orientation and dimensions in the office. The geometric computation works, but the DWG export does not correctly reproduce the block’s rotation or size—the result in AutoCAD is incorrect and unusable as is.
Have you implemented a similar workflow? What tools or methods do you use to ensure that the DWG export is directly usable by drafters without requiring rework? Thanks in advance for your help.
