Help with dwg -> kml conversion

[jimmy.nylund_rapal]

Hi,

I have a project in which I need to convert some information to KML from DWG. I have been trying to do this with Autocad Map 3D, but have not fully succeeded, and was hoping someone could help me out, point out what I'm doing wrong or give me some advice on alternative ways to convert dwg to kml.

As an example file (I'll attach this post), I have made a circle in the center of the Helsinki railway station, and am trying to convert it to kml. For some reason I can not seem to get the coordinates right at all. The coordinates I get out in the kml file is instead focused around 20°N 50°E which is in not nearly in the vicinity of Helsinki.

Here is how I am trying to do the conversion:

• I start by choosing geographic location (GEOGRAPHICLOCATION), and from the online map data, I place the marker on Helsinki Central Railway Station (60.1719,24.9414)
• 
• Next I choose a coordinate system based on WGS84, and perhaps it is here where I go wrong. I choose the EURO-LM-CONIC, because I don't know what else to choose. And I select GMT+2:00 Helsinki as Time Zone.
• 
• Next I choose to put the marker at location 0,0,0 in my drawing with North pointing up (90degrees)
• I add some objects, for example the circle as in my example file.
• 
• I use MAPEXPORT to export the objects to KML.
• End result: circle / objects supposed to be in Helsinki are now somewhere completely different in the KML file

Anyone who can help me with this problem? I don't understand why the coordinates are suddenly 20°N 50°E in the KML file. 

Attached also the dwg but unfortunately I can't seem to attach the kml file, so I'll just copypaste it here.

converstiontest.kml:

<?xml version="1.0" encoding="UTF-8"?>

<kml xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:gx="http://www.google.com/kml/ext/2.2" xmlns:atom="http://www.w3.org/2005/Atom" xmlns="http://www.opengis.net/kml/2.2">
<Document>
<name>conversiontest</name>
<visibility>1</visibility>
<Folder id="kml_ft_conversiontest">
<name>conversiontest</name>
<Placemark id="kml_1">
<name>kml_1</name>
<Style>
<LineStyle>
<color>ffffffff</color>
</LineStyle>
</Style>
<Polygon>
<outerBoundaryIs>
<LinearRing>
<coordinates>20.0042489570959,49.9999999218034,0.0 20.0042328095989,50.0002386229927,0.0 20.0041844473856,50.0004755086928,0.0 20.0041042380562,50.0007087760203,0.0 20.0039927916157,50.0009366496048,0.0 20.0038509558443,50.0011573951018,0.0 20.0036798098571,50.0013693323955,0.0 20.0034806559021,50.0015708483882,0.0 20.0032550094577,50.0017604092815,0.0 20.0030045877046,50.0019365722529,0.0 20.0027312964618,50.0020979964417,0.0 20.0024372156824,50.0022434531581,0.0 20.0021245836233,50.0023718352394,0.0 20.001795779807,50.0024821654799,0.0 20.0014533069052,50.0025736040734,0.0 20.001099771684,50.0026454550072,0.0 20.0007378651546,50.0026971713639,0.0 20.0003703420806,50.0027283594851,0.0 20.0,50.0027387819705,0.0 19.9996296579194,50.0027283594851,0.0 19.9992621348454,50.0026971713639,0.0 19.998900228316,50.0026454550072,0.0 19.9985466930948,50.0025736040734,0.0 19.998204220193,50.0024821654799,0.0 19.9978754163766,50.0023718352394,0.0 19.9975627843176,50.0022434531581,0.0 19.9972687035382,50.0020979964417,0.0 19.9969954122954,50.0019365722529,0.0 19.9967449905423,50.0017604092815,0.0 19.9965193440979,50.0015708483882,0.0 19.9963201901429,50.0013693323955,0.0 19.9961490441557,50.0011573951018,0.0 19.9960072083843,50.0009366496048,0.0 19.9958957619438,50.0007087760203,0.0 19.9958155526144,50.0004755086928,0.0 19.9957671904011,50.0002386229927,0.0 19.9957510429041,49.9999999218034,0.0 19.995767232536,49.9997612217984,0.0 19.995815635604,49.9995243396156,0.0 19.9958958832664,49.9992910780312,0.0 19.9960073643536,49.9990632122413,0.0 19.9961492300328,49.9988424763535,0.0 19.9963204002799,49.9986305501916,0.0 19.9965195721098,49.9984290465151,0.0 19.9967452295013,49.9982394987482,0.0 19.9969956549407,49.9980633493146,0.0 19.9972689424972,49.9979019386635,0.0 19.9975630123296,49.9977564950735,0.0 19.9978756265136,49.9976281253085,0.0 19.9982044060701,49.9975178061997,0.0 19.9985468490642,49.9974263772155,0.0 19.9989003496386,49.9973545340762,0.0 19.999262217835,49.9973028234627,0.0 19.9996297000543,49.9972716388587,0.0 20.0,49.9972612175577,0.0 20.0003702999457,49.9972716388587,0.0 20.000737782165,49.9973028234627,0.0 20.0010996503614,49.9973545340762,0.0 20.0014531509358,49.9974263772155,0.0 20.0017955939299,49.9975178061997,0.0 20.0021243734864,49.9976281253085,0.0 20.0024369876704,49.9977564950735,0.0 20.0027310575028,49.9979019386635,0.0 20.0030043450593,49.9980633493146,0.0 20.0032547704987,49.9982394987482,0.0 20.0034804278902,49.9984290465151,0.0 20.0036795997201,49.9986305501916,0.0 20.0038507699672,49.9988424763535,0.0 20.0039926356464,49.9990632122413,0.0 20.0041041167336,49.9992910780312,0.0 20.004184364396,49.9995243396156,0.0 20.004232767464,49.9997612217984,0.0 20.0042489570959,49.9999999218034,0.0</coordinates>
</LinearRing>
</outerBoundaryIs>
</Polygon>
</Placemark>
</Folder>
</Document></kml>

.

[ChicagoLooper · Accepted solution]

Hi @jimmy.nylund_rapal 

You're correct, you're not doing it right.

First of all, you don't really want to 'convert' your drawing to kml. What you want is a geospatial drawing so it's properly referenced to the equator and north pole.

You are getting the Lat/Long from Google Earth but you don't mention the desired or target coordinate system you wish to work with--there are multiple that you can use for Helsinki.

Do this:

1. Open a clean, brand NEW metric template. 
2. On command line enter MAPCSASSIGN=>In search box enter FINLAND 
3. Scroll down=>Select ETRS89.TM-35/Fin, EPSG 3037=>Click ASSIGN. (Your actual target Coord System may vary.)
4. Go to Geolocation Tab=>Online Map Panel=>Change Map off to BING HYBRID. (The Microsoft Bing logo will appear in lower right of modelspace. Be patient and wait for the logo.)
5. Slowly zoom-out until you see red geomarker. (It looks like a red bicycle wheel with red spokes.)
6. Zoom in on Bing Map. Using the labels in Bing Hybrid, use PAN and ZOOM to navigate to Helsinki Railway Station.

[ChicagoLooper · Accepted solution]

Hi @jimmy.nylund_rapal 

With your coordinate system properly assigned to modelspace, you can verify the Lat/Long coordinates. The coordinates will be LIVE and will instantly update as you move your cursor.

1. On command line enter MAPTRACKCS.
2. Then select LL84 by doing this. (Lat Longs=>scroll down to LL84.)
3. To increase the precision (decimal places) of the coordinates displayed in MAPTRACKS enter UNITS on command line=>go to LENGTH=>PRECISION=>increase the precision using the dropdown.

[jimmy.nylund_rapal]

Thanks @ChicagoLooper this was exactly the kind of step-by-step guide I was hoping for! 🙂 

I now managed to export the needed objects for my customer to the kml format and it looks perfect! Thank you very much!