How to Check Point Cloud Accuracy in 3Dsurvey
Introduction to Accuracy Assessment
In this 3Dsurvey tutorial, we’ll cover how to quickly check the accuracy of your 3D point cloud by comparing it with independently measured checkpoints collected via an RTK GPS rover.
Importing GPS Checkpoints
To begin, import your checkpoints from the GPS rover. Go to Data -> Load CAD
and select the TXT file with the GPS checkpoint positions.
Measuring Height Differences
To verify point cloud accuracy, measure the height difference between the GPS points and point cloud. Access the CAD Tools
menu, select the Ruler
tool, disable the 3D distance option, and choose Height.
Clicking on the point and moving your cursor allows you to measure the height difference. Right-click to mark the point and save the measurement.
Interpreting Results for Survey Grade Accuracy
For survey-grade accuracy, aim for a height difference of 4 cm or less between checkpoint and point cloud points. In our case, the accuracy for both checkpoints is around 2 cm, verifying that our point cloud achieves survey-grade precision.