Due to their low cost and ease of deployment, fiducial markers – primarily Quick Response (QR) codes – gained widespread popularity over the past decade. Given their original use cases in logistics, these markers were created with the goal of transmitting a single static payload. We introduce QRUco as an approach to create cheap yet interactive fiducial markers. QRUco uses thermochromic paint to embed three secondary markers into QR code finder patterns. Users may interact with these markers through rubbing or pressing/touching, thereby changing the appearance of the marker while leaving the primary QR code intact. In this paper, we present the QRUco concept and demonstrate that our proposed approach is effective. We emphasize that QRUco markers can be created cheaply and that they do not require any specialized scanning equipment. We furthermore discuss limitations of the proposed approach and propose application domains that would benefit from QRUco.

Kay Erik Jenss, Simon Mayer

18 Feb 2023