Daily Archives: September 21, 2019

What is the difference between Geopose and GPS?

The two previous posts on this blog are the result of trying to create a definition of geopose. I still have not come up with a twenty-word-or-less definition. However, the following is very helpful towards achieving that goal.

What you are about to read is a reply sent to me by Jan-Erik Vinje, the Managing Director of the Open Augmented Reality Cloud. Jan-Erik and I will both be giving presentations at the 2nd Open Augmented Reality Cloud Symposium in Munich on October 16th.

If you are serious about AR, please listen to the AR Show podcast featuring the four" workhorses" of the AR cloud.

Download the First State of the AR Cloud report as well. You can find it here.

Jan-Erik Vinje's thoughts on the differences between GPS and Geopose:

  • GPS is a specific technology. And it is mostly used for obtaining more or less accurate geospatial positions related to a geospatial coordinate reference system. Currently an ellipsoide that approximates the earth is used to as the reference for altitude and longitude. The ellipsoid is a bit crude but it is normally less than 100 meters incorrect as a representation of where the main ocean surface is or would have been.
  • GeoPose is intended to relate to the same type of geospatial reference but adds geospatial orientation to the geospatial position. All real objects on our planet could in principle be said to have both a position and orientation. GPS provides position. If you have a stream of GPS positions you could derive a direction vector that is almost an orientation but not quite. Imagine walking down the street with a smartphone and imagine collecting a GPS location ( lat, lng, alt) every second. You can create a path through space telling you the direction you have moved with phone. What the GPS locations can not give you is the orientation you have held your device. Did you point it towards the ground, to the sky or towards a Wall across the street, and importantly how was your device rotated around that direction?
  • For that you would need another system or set of systems to provide you with your orientation. AR Cloud visual positioning systems can provide both the position and the orientation of your device. This is what we call a pose. If that position and orientation is in a geospatial frame of reference equivalent to the one used for GPS one can call the pose a geopose.
  • (SB:Hmmm that is great, but the last three lines will require a bit of serious thought...I am not 100% clear I understand. When I do, I hope to make educational drawings, or better, 3D models-in AR.)