Extrinsics Calibration#

Introduction#

In this tutorial, we will discuss how to perform an extrinsics calibration for a Duckiebot’s camera inside the Duckiematrix.

This demo is designed to work with the map loop_0, which can be found in the duckiematrix-examples repository. For this demo, using a vehicle with different intrinsic camera parameters from those of map_0/vehicle_0 in loop_0 will affect the result.

Step 1: Run the camera demo#

Before proceeding, run the I/O: Camera demo.

Step 2: Go to the laboratory#

In the Duckiematrix window:

  • select Mayor’s View (top-right corner of the window)

  • walk up to the Duckiebot you see on the road

  • press the E key to hop onto the Duckiebot

  • use the W, A, S and D keys to drive the Duckiebot

  • drive to the laboratory’s driveway and then press the F key to enter the building

  • select the Extrinsics Calibration tool (bottom-center of the window)

Step 3: Wait for a good detection#

The matplotlib window opened during Step 1: Run the camera demo will show the corners detected on the patterned board, as shown in the following image:

../../../_images/extrinsic_calibration.png

Once you see a clear and correct detection of all of the corners, press the ENTER key in the first terminal and the estimated homography will be printed to screen.