Home
build details

Show: section status errors & todos local changes recent changes last change in-page changes feedback controls

Camera calibration and validation

Modified 2018-11-07 by tanij

This section describes the instrinsics and extrinsics calibration procedures.

You can see the camera image on the laptop. The procedure is documented in Unit B-9 - See what your Duckiebot sees.

You have configured Docker communication as documented in Unit B-7 - Setting up the Docker workflow.

You have a camera calibration pattern Section 10.1 - Materials.

Calibration for the robot camera.

Materials

Modified 2018-11-07 by tanij

If you do not have one already, download and print a PDF of the calibration checkerboard:

the squares must have side equal to 0.031 m = 3.1 cm. Please measure this, as having the wrong size will make your Duckiebot crash.

In case your squares are not of the right size, make sure your printer settings are on A3 format, no automatic scaling, 100% size.

Fix the checkerboard to a rigid planar surface that you can move around.

If the pattern is not rigid the calibration will be useless. You can, e.g., print on thick paper to achieve this.

Perform intrinsics calibration

Modified 2018-11-03 by breandan

Note: you can now use dts duckiebot calibrate_intrinsics hostname to run intrinsic calibration only. (you will be able to check if ros-picam is running before proceeding with calibration)

You should see a display screen open on the laptop (Figure 10.4).

Extrinsic Camera Calibration

Modified 2018-09-27 by liampaull

Setup

Modified 2018-11-03 by breandan

Note: you can now use dts duckiebot calibrate_extrinsics hostname to run extrinsic calibration only.

Arrange the Duckiebot and checkerboard according to Figure 10.10. Note that the axis of the wheels should be aligned with the y-axis.

Figure 10.12 shows a view of the calibration checkerboard from the Duckiebot. To ensure proper calibration there should be no clutter in the background.

No questions found. You can ask a question on the website.