Collecting and Processing GCPs in Lixel Studio

This article will demonstrate how to collect ground control points during your XGRIDS SLAM LiDAR scan that you can then tie to real world coordinates collected with your GNSS receiver, such as the RS3. Lixel Studio version 3.2.0.0 is featured in this video. This version of Lixel Studio doesn't yet natively support Imperial linear units, Orthometric height, or State Plane projections. This current limitation is the reason the GNSS coordinates were collected in UTM Zone 17N, Ellipsoidal Height, and metric linear units. Expected formatting for control points in Lixel Studio is PENZD. 

In this article we will demonstrate how to incorporate ground control points in your XGRIDS LiDAR scan. We'll collect my GCP coordinates with my Emlid receiver first, the during the scan I will collect those same points as GCPs. Note that the current version of Lixel Studio version 3.2.0.0 doesn’t yet support imperial measurements or State Plane coordinates so I’ll use UTM Zones and metric units. Once we have our scan and our coordinates for GCPs, we can export a CSV with our GCP coordinates and download our project from the scanner.  

We'll create a project in Lixel Studio and then go to Project processing. I select the project folder from my scan and deselect GNSS since we will be using GCPs for our geolocation. Then under GCPs, I’ll select the CSV file containing my coordinates, then select GCP edit to confirm that my coordinates collected with my GNSS receiver correlate correctly with the GCPs collected during the scan. You can confirm visually but the Check button will also compare and let you know if there are any outliers to correct. The last thing we'll do before processing is confirm I’m outputting the processed project where I want it, then I’ll click Start. Now that the processing has finished, we have our cleaned-up point cloud geolocated with our ground controls.