Digitizing Interlocking Building Blocks

Abstract

Interlocking building blocks (such as LEGO®) are well-known toys and allow the creation of physical models of real objects or the design of imaginative 3D structures. In this paper, we propose a novel approach for digitizing building blocks with the original LEGO® form factor. We add a microprocessor to each 4 x 2 block, and the blocks communicate with each other via a two-wire connection provided in every nub. This poses the additional challenge that communication and power supply must use the same two-wire connection, which is addressed by alternating between the two modes over time. We introduce a protocol that checks for connections and propagates all connection information through the block network. We can then pass this information to a connected computer, which reconstructs the structure of the block network. We present several successfully digitized example configurations and discuss failure cases. Furthermore, two end-user scenarios are demonstrated, which show the potential of our approach as an intuitive human-computer interface.