Data Collection for Vehicle-Camera Calibration (deprecated)
Calibration Target:
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. https://drive.google.com/file/d/1mTR8HTpvROE1Pv0rmXEBVLSxs_yMDnvf/view?usp=sharing
For car wheels either the Aruco markers can be used or the sechhi disk can be used.
Data collection for vehicle-camera calibration:
  1. 1.
    We need two cameras, one mounted on the car w.r.to which we do the calibration against the vehicle.
  2. 2.
    We need to make sure we have the intrinsic parameters for both the cameras before we proceed to vehicle-camera calibration. Intrinsics can be obtained from the camera-LiDAR calibration tool as well.
  3. 3.
    Data must be collected twice. One for the left view and the other for the right view. Both have the same steps.
  4. 4.
    Have a checkerboard with known horizontal corners and vertical corners. And also the square size.
  5. 5.
    A sticker can be attached to the car wheel to auto-detect the center of the wheel. In case AruCo markers being selected in the vehicle configuration page, the user needs to attach the PDF file printout present at the following location https://drive.google.com/file/d/1L8lwFvasGEdkrAsibkS5tKFp5MFk399y/view?usp=sharing
Front Left:
Front Right:
Rear Left:
Rear Right:
6. In the case of AruCo markers, the labels representing marker wheel relation is present on top of every page.
Data collection for left view set-up: 1. Place the checkerboard in the field of view of the mounted camera. And freeze the position of the checkerboard. 2. The Mounted camera should take a single frame by having the checkerboard in its frame.
3. External cameras should take a single frame by having the checkerboard and both the left wheel tyres of the car.
4. Now the external camera can be placed at a different angle and another frame must be taken.
Example for AruCo tag:
5. A minimum of 2 images are required, but any number of images can be added.
The same above steps must be repeated for the right view set up as well.
Examples for the right view are
Last modified 5mo ago
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