topic Re: AutoCAD Map 3D 2018 Coordinate Transformation in AutoCAD Map 3D Forum

AutoCAD Map 3D 2018 Coordinate Transformation

elijah — Fri, 12 Jan 2018 05:24:01 GMT

Hello,

Can anyone help me.

My AutoCAD Map 3D 2018 is unable to transform local coordinate system(MAUSON 7P) into other coordinate system such as UTM WGS 84.

This is urgent.

Warm Regards

Re: AutoCAD Map 3D 2018 Coordinate Transformation

Pointdump — Fri, 12 Jan 2018 10:50:39 GMT

Elijah,

Need some particulars on the MAUSON 7P Coordinate System. What part of the world is it in?

Dave

Re: AutoCAD Map 3D 2018 Coordinate Transformation

parkr4st — Fri, 12 Jan 2018 13:41:31 GMT

Dave

it maybe this? MAISON 7P Coordinate System

Dave P

Re: AutoCAD Map 3D 2018 Coordinate Transformation

elijah — Fri, 12 Jan 2018 13:44:36 GMT

MAUSON 7P Coordinate System is one of the commonly used coordinate system in Mauritius, an Island in Indian Ocean.

Regards

Re: AutoCAD Map 3D 2018 Coordinate Transformation

Pointdump — Fri, 12 Jan 2018 14:59:19 GMT

Elijah,

I haven't been able to find any information about Mauson 7P. A search for Mauritius in _MAPCSLIBRARY turns up this:

And a search in the <<<EPSG Registry>>> turns up this:

So I guess the next step is to figure out exactly the parameters of the Mauson 7P Coordinate System and either modify an existing Coordinate System or create one from scratch.

Look through <<<This Link>>> and see if anything there will suit.

Dave

Re: AutoCAD Map 3D 2018 Coordinate Transformation

Pointdump — Fri, 12 Jan 2018 19:19:53 GMT

Dave P,

Google suggested the alternate spelling of "Maison", but that was a dead end.

Do you have Global Mapper? I've been thinking about getting it. Between Global Mapper and QGIS, almost every Coordinate System is represented. I didn't find it in QGIS:

Dave S

Re: AutoCAD Map 3D 2018 Coordinate Transformation

parkr4st — Fri, 12 Jan 2018 20:14:23 GMT

try this site

http://georepository.com/crs_3337/Le-Pouce-1934-Mauritius-Grid.html

dave p

Re: AutoCAD Map 3D 2018 Coordinate Transformation

Pointdump — Fri, 12 Jan 2018 23:02:13 GMT

Dave P,

The Georepository Site is good. I use it quite a bit.

Dave S

Re: AutoCAD Map 3D 2018 Coordinate Transformation

elijah — Sat, 13 Jan 2018 06:56:59 GMT

Hello Dave,

Thanks a lot for your effort in helping to resolve this. I am also doing my research on the same. Will get back to you if I manage to get a different solution.

Warm Regards

Re: AutoCAD Map 3D 2018 Coordinate Transformation

Pointdump — Sun, 14 Jan 2018 21:35:17 GMT

Elijah,

I think this is the Projection you're looking for. From <<<Clifford J Mugnier's White Paper>>>:

"To cater for plane surveys, a plane coordinate system has been devised that minimizes the effect of projection scale factor. It is based on GDM2008 datum and Lambert Conformal Conic Two Parallel map projection and is referred to as the Local Grid Mauritius 2012 (LGM2012)"

From <<<This PDF>>>:

LOCAL GRID MAURITIUS 2012
The LGM 2012 shall be based on the following parameters –
(a) Datum : GDM 2008
(b) Origin :Verdun PTP0391
(c) Projection : Lambert Conformal Conic Two Parallel
(d) Central latitude : 20° 16' 31.85868" S
(e) Central longitude : 57° 33' 52.40384" E
(f) False easting at Origin : 250,000.00 mE
(g) False northing at Origin : 350,000.00 mN
(h) Parallel 1 : 20° 03' 40.0" S
(i) Parallel 2 : 20° 26' 40.0" S
(j) Scale factor at parallels : 1.00000

Dave

Re: AutoCAD Map 3D 2018 Coordinate Transformation

Pointdump — Mon, 15 Jan 2018 02:57:16 GMT

Elijah,

Here's my best guess at creating your desired Coordinate System. When you open the attached drawing, it will ask you whether you want to add "Mauritius_LGM-2012" to your CS Library. I created this drawing with Civil 3D, so you won't see the points if you're using Map 3D. I've attached the Mauritius Shapefile and a CSV file of Primary Control Points.

Dave

Re: AutoCAD Map 3D 2018 Coordinate Transformation

elijah — Mon, 15 Jan 2018 10:54:32 GMT

Dave,

Thank you. I was able to add Mauritius_LGM-2012 to my CS Library.

Re: AutoCAD Map 3D 2018 Coordinate Transformation

Pointdump — Mon, 15 Jan 2018 11:45:22 GMT

Elijah,

I think I screwed up. Further testing shows points added with Lats and Longs don't work as expected. I'll work on it and see if I can fix it.

Use _MAPCSLIBRARY >> View to look at this User-Defined CS. First thing to notice is that I didn't use "-" for the Latitude definitions. Oopsie!

Dave

Re: AutoCAD Map 3D 2018 Coordinate Transformation

Pointdump — Mon, 15 Jan 2018 17:40:53 GMT

OK, fixed. Lats and Longs plugged in look right, and exporting the Admin Boundaries as SHP works perfectly in QGIS. (QGIS recognizes the custom projection defined in the PRJ) So delete that first custom projection in Map and when you open this attached drawing you'll get a correct Coordinate System added to your Library.

Dave