Data Collection for Vehicle-Camera Calibration
Checkerboard is the calibration target. A large checkerboard is required because the external camera is usually quite far away. For small vehicles (car), the minimum checkerboard size is 0.6m^2. For large vehicles (e.g. farm tractor), the minimum checkerboard size is 2.4m^2 because the camera is further away. If you are calibrating a small vehicle, you can print the attached pdf file on a foam board at 1.0m x 0.6m. Most print shops can print this.
Data collection for vehicle-camera calibration:
  1. 1.
    We need one mounted on the car w.r.t which we do the calibration against the vehicle.
  2. 2.
    We need to make sure we have the intrinsic parameters for the cameras before we proceed to vehicle-camera calibration. Intrinsics can be obtained from the camera-intrinsic calibration tool as well.
  3. 3.
    Have a checkerboard with known horizontal corners and vertical corners. And also the square size.
  4. 4.
    Mark the boundaries of the vehicle using the tape, then mark a parallel line to the vehicle based on the orientation of the camera
  5. 5.
    Use tape in order to take precise measurements, along with a carpenter scale, to make sure the board is exactly perpendicular to the ground
  6. 6.
    Place the board on this parallel line
  7. 7.
    Make sure the board is parallel or perpendicular to the car sides, based on the configuration of the camera
  8. 8.
    Take measurements of the checkerboards distance from the respective side of the vehicle by measuring the distance of the parallel line the checkerboard is on to the vehicle side it is parallel to and also measures how far the checkerboard is, from the left side of the line
  9. 9.
    Take multiple shots of the checkerboard with the checkerboard placed at multiple distances away from the left, along the same parallel line.
  10. 10.
    Also, measure the required vehicle config
Example photo 1 of the checkerboard
Example photo 2 of the checkerboard
Required vehicle configuration for rectangular vehicle
Required vehicle configuration for trapezoid vehicle
Last modified 5d ago
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