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GNSS/IMU .csv log file

Hardware: aircraft=M600, camera=Sony A7R with gimbal and NINJA interface, flight planning software= Map Pilot, post process software=UASMaster by INPHO

Current Issue.

Post flight .csv GNSS/IMU file log is too cumbersome and not accurate:

  • File records from startup at an interval of once every 10th of a second.
  • Average .csv file is 50 columns by 12,000-15,000 rows! Massive!
  • Image column is somewhat reliable on flat ground but in steep terrain it skips images.
  • There can be 10-50 rows recorded per image. In other words there can be as many as 50 GNSS/IMU entries marked as the same photo. The GNSS/IMU data set needs to be selected manually.
  • CSV file image numbers are not correlated to the image ID from the camera. This must be done manually.

Best work around so far:

  • Manually sort photos based on YAW.
  • Manually remove non flight line photos.
  • Manually script the .csv to ID flight lines based on YAW.
  • Manually correlate GNSS/IMU data row with photos
  • Delete all unnecessary rows and columns to produce a .csv that contains only one photo id, lat, long, altitude, yaw, pitch, roll for each photo.
  • This process takes hours, in fact a full day for a large site.

What I need is Map Pilot to record 1 GNSS/IMU data row per photo and correlate it correctly to the photo ID.

Questions:

  • What do other GNSS/IMU .csv files look like that have been recorded using different cameras and aircraft?
  • Has this issue been discussed before on this forum? If so, can you direct me to those threads?

Any feedback would be appreciated.

Thank you,

Bruce

Bbrown

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The lines marked with 'Photo' should be interpreted as the single sample at which time the image was taken. There are not 10-50 rows per sample, just that one.

The 'Photo' markers are created when the aircraft tells the app it too an image so if you do not have a good RC connection it is possible for it to get dropped. 

All telemetry is recorded and is reported at 10 Hz. 

Zane

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Thanks for the quick response Zane.

The "Photo" search will help a great deal as it is hidden in the 54th column "BB" that is labeled "App_Tip". I never would have thought to look there and I would not have known what to look for. I was using the 12th column "L" labeled "Image" which shows the current image number for each of the 10th of a second recordings.

Is the normal GNSS/IMU output file from Map Pilot 59 columns wide and recorded every 10th of a second? If this is the case I would like to pursue a modification to Map Pilot or a direct embedding of the data on the photo for my purposes. I'll write you a email direct.

Thank you,

Bruce

Bbrown 0 votes