April targets

1. What do April tags do?
2. How many April tags are there?
3. Who invented AprilTags?
4. How accurate are AprilTags?

What do April tags do?

AprilTag is a visual fiducial system, useful for a wide variety of tasks including augmented reality, robotics, and camera calibration. Targets can be created from an ordinary printer, and the AprilTag detection software computes the precise 3D position, orientation, and identity of the tags relative to the camera.

How many April tags are there?

There are 2 generations of AprilTag families, Apriltag 2 and AprilTag 3. AprilTag 2 is the classic Apriltag. Apriltag 2 (gen2) should be used if you want a better out of box experience.

Who invented AprilTags?

An AprilTag is a pattern of dark and light squares similar to a QR code but easier for cameras to detect robustly and at a distance. AprilTags were created by Associate Professor Edwin Olson ([email protected]), EECS, University of Michigan. See https://april.eecs.umich.edu/.

How accurate are AprilTags?

They achieved an accuracy of 1.77 cm for the position and 4.15◦ for orientation estimation. Some researchers have used AprilTag as a landmark and track it in robotics applications.