Coordinate Transformation Tool (BETA)

4 min. readlast update: 10.18.2023

Xsite® MANAGE provides a powerful tool for creating local coordinate transformations. PRM Tool is suitable for mines and construction sites which doesn´t use any national coordinate systems.

PRM file type is required into Xsite® machine control systems and Xsite® PAD.  

Local coordinate transformation use cases

  • In the railway maintenance coordinate system is not consistent with the national coordinate system.
  • Construction site is small, and designs are not fitted into earthmoving construction.
  • Mining construction often use local grid coordinates instead of national coordinate systems. 
  • BIM expert converts architectural designs automatically with the coordinate transformation tool and there is no need to convert each design manually. The goal is to eliminate human errors in the transformations. 
  • Ground shift is moving regularly and there is a need to create coordinate transformation after continues to tectonic movements.
  • There is a need to improve the transformation accuracy because third party software conversion is not accurate enough.
  • Cities and towns may use local coordinate transformations on earthmoving construction sites. 

From WGS84 to grid coordinates

With the PRM tool you can create your own local coordinate file for the Xsite machinecontrol systems.

This is done by adding the coordinates for at least two points in the WGS84 (Lat/Lon/Elev) system and also adding the local coordinates (NEH/XYZ) for the same points.

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Points in local grid coordinates and in WGS84 coordinates

The points should be outside of the worksite so that the local coordinate transformation will cover the whole worksite. 

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Supported import formats at the moment 

  •  Trimble CAL
  • Trimble JobXML
  • SBG
  • HeXML
  • Trimble DC
  • Topcon MAXML
  • Carlson XML
  • CSV
  • Topcon GC3

Surveying and transformation of virtual points

  1. Measure with GNSS device and compare the points to the local coordinate system of the construction site. 
  2. An object on the construction site is measured with a GNSS measuring device. The object can be found in the design plan with the coordinates of the construction site. The coordinates of the plan are used as a reference point. 
  3. Do the transformation of virtual points with a cad program and export points for the PRM tool. 

How to use the PRM tool - step by step

  • Give a name to the new PRM file.
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  • Import coordinates from import file 
    • You can choose to drag and drop or upload a coordinate-file into the drag and drop box. 
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  • After importing the XML based file format . The coordinate pairs will appear in the coorninate fields. 
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Accurate transformation will require at least 5 points. Bigger worksites may require more points to create more accurate transformation. As Xsite® MANAGE user click on Add a new coordinate pair button to add new coordinate pair. 
Xsite® MANAGE will show the RESIDUALS and the user can choose which points are included in the PRM export by using IN USE -selection.
If the Northing/Easting are in wrong order for some reason. You can switch the coordinates by using Switch northing/easting button. 

CONVERT LATITUDE AND LONGITUDE TO DD, DMS OR DDM

The WGS84 coordinates can be given in 3 different formats: DD (Decilmal Degrees), DMS (Degrees, Minutes and Seconds) and DDM (Degrees, Decimal Minutes)

DD (Decimal Degrees)

DD uses mathematical operators, plus and minus, to indicate the offset from the common references (e.g. 64.041385, -16.181383). This makes DD different and recognizable and, since this format can be represented by a simple pair of Float values, a great choice for IT/software applications. 

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DMS (Degrees, Minutes and Seconds)

Classic representation of latlong coordinates, pretty much understandable by everyone. If you are wondering what time units of measures do in this discussion, DMS use North/South, East/West explicitly to indicate the direction of the offset from Greenwich and the Equator (e.g. 45°45’32.4″N 009°23’39.9″E).  

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DDM (Degrees and Decimal Minutes)

DMS sounds like a combination of the two: it uses Degrees, followed by Minutes and Decimal of minutes, rather than seconds. Since DMM and DMS look similar, they can be confused quite easily. DDM is recognizable as the seconds are represented as decimals of minutes rather than sexagesimals, and their typical indicator (quotation mark:  ) is absent.  

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To create a PRM file, press the CALCULATE TRANSFORMATION PARAMETERS button. 

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