Camera IDS resolution calculation - WARRExploration/Rover_II GitHub Wiki

  • Sponsored industrial cameras from IDS
  • Current plan is to have two UI-3280CP cameras for stereo vision
  • Different camera sensors we could use have different resolutions, and using objectives of different focal length (F) gives different field of view (FOV)
  • We need enough resolution to reliably detect QR codes on the ERC landmarks (with the "ar_track_alvar" ROS package). Using experiments in Gazebo/Rviz we found that at 2 pixels per QR code square we get occasional detection, and at 3px reliable detection.

Resolution calculation How to

  • Use the Lens calculator from IDS. Input the camera model you want to use, or go to the lensfinder via the aperture icon on the camera model page.
  • Each QR code square is 1.5cm high. Therefore, at max working distance we need a horizontal width of 5mm/px * horizontalResolution for a resolution of 3px per square
  • Choose a 'Focal length' value for the objective. Then increase 'Working distance' until the 'Width max' is near the required width. Then read out FOV angle and max detection range.

Calculated results for different sensors:

(Assuming: 5mm/px or 3px per marker square)

IMX178: 3088 x 2076
F      horFOV  horWidth   maxRange
12mm   34,3°   15440mm    25m
8mm    49,7°   15440mm    16,5m
6mm    63,4°   15440mm    12,5m

IMX265: 2048 x 1536
F      horFOV  horWidth   maxRange
12mm   32,9°   10240mm    17m
8mm    47,8°   10240mm    11,5m
6mm    61,1°   10240mm    8,5m

IMX264: 2456 x 2054
F      horFOV  horWidth   maxRange
12mm   38,9°   12280mm    17,5m
8mm    55,8°   12280mm    11,5m
6mm    70,4°   12280mm    9m