Calibration - Kinematics#

This section describes how to perform the kinematics calibration procedure for your Duckiebot.

What you will need

You can make your Duckiebot move.

What you will get

Your Duckiebot’s kinematics will be calibrated.

Attention

Complete both the camera and kinematics calibration procedures before running any Duckietown demos.

The easiest way to perform the kinematics calibration procedure for your Duckiebot is by using the Keyboard Controller.

../../_images/keyboard_controller.png

Fig. 62 The Keyboard Controller.#

To activate the Keyboard Controller, run:

dts duckiebot keyboard_control ![DUCKIEBOT_NAME]

Note the keys in the table below.

Key

Function

W

Drive forwards

S

Drive backwards

A

Turn left

D

Turn right

E

Toggle the Emergency Stop switch

F

Toggle the Autopilot switch

X

Increase the Gain

Z

Decrease the Gain

V

Increase the Trim

C

Decrease the Trim

Space

Save the Gain and Trim

R

Refresh the window

T

Open the Debug Console

Procedure#

To perform the kinematics calibration procedure:

  1. Create a slightly greater than 2 m long straight line on your floor using tape

  2. Place your Duckiebot at one end of the line

  3. Note your Duckiebot’s position

  4. Face your Duckiebot towards the other end of the line

  5. Drive your Duckiebot forward for about 2 m

  6. Note your Duckiebot’s position

  7. Measure the distance between the center of the tape and the center of your Duckiebot’s axle using a ruler, making sure that the ruler is perpendicular to the tape

  8. Decrease (resp., increase) the Trim and repeat steps 2-8 if your Duckiebot drifted to the left (resp., right) side of the tape by more than 10 cm

  9. Set the Gain

  10. Click the Save button

../../_images/wheel_calibration_line.jpg

Fig. 63 A straight line used for the kinematics calibration procedure.#

../../_images/wheel_calibration_lr_drift.jpg

Fig. 64 Left/right drift.#

../../_images/wheel_calibration_measuring_drift.jpg

Fig. 65 Measuring the amount of drift after driving forward for about 2 m.#

To confirm that a new kinematics calibration file has been created on your Duckiebot, run the following command and inspect the contents of the Kinematics panel:

dts duckiebot dashboard ![DUCKIEBOT_NAME] --page robot/calibrations
../../_images/kinematics_panel.png

Fig. 66 The Kinematics panel on the Robot page of the Dashboard.#

Note

Within the Kinematics panel, under Local, you should see a tick next to Completed, the calibration date next to Calibration date and /data/config/calibrations/kinematics/![DUCKIEBOT_NAME].yaml next to Files.

For more information on odometry and odometry calibration, review:

Troubleshooting#

Troubleshooting

SYMPTOM

My Duckiebot does not move after going through Operation - Make it Move - Troubleshooting.

RESOLUTION

Contact support.