LiDAR Calibration

Calibration of LiDAR data is the most difficult process to perform when developing LiDAR data. It doesn’t matter if you have any one manufactures type of system. Each system has its own characteristics. It doesn’t matter if it is the same make and model. The results from the sensors will vary. The inconsistent variable is Roll. Roll changes continually on most systems. Some systems hold calibration better than other but it seems the calibration needs to be checked continuously. The second most inconsistent variable is the pitch and then depending on system the scan factor error and pitch slope error. Typically, I have never seen a needed adjustment to the yaw once it is set by any manufacture. There are several variables that should not be adjusted in calibration or only adjusted by the manufacture. Typically, these variables will be provided by the manufacture. Comments regarding this subject are welcome.

Advertisements

3 Responses

  1. For the leica PP on the POS error entry window there is a note that “The picth error slope, PPS correction and IMU latency should be set to 0 in most situations”

    When should you put in a value for pitch slope error?
    Do you have any suggestions on how to best calculate pitch slope error?

  2. The best way to figure out if you have a pitch slope error is to look at the pitch error at NADIR or the center of a flight line and correct for this error and eliminate it. Once this is done you can go to the edges of the scan and see if you have and edge pitch error. If you do this is a pitch slope error. We typically fly a calibration of over the airport of two lines in opposite directions. At minimum one line in the project site should be flown in opposite directions. if you have this the pitch slope error calculation is as follows: edge of flight line pitch error minus NADIR pitch error divided by FOV over 2. Both our Lieca sensors have adjustments for Pitch slope error roughly around 4e-005 radians where (radians of correction per degree of off NADIR). Once this is calculated it stays constant for the most part, but sometimes needs a minor adjustment.

  3. Nice post, I have never seen a needed adjustment to the yaw.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: