Autonomous, Self-Assembling Robots

Step 5 Microcontroller code

i've attached the AVR microcontroller code below. the code implements the following self-assembly algorithms which are shown in the videos:

1) line-forming. a mixed set of yellow and green tiles will assemble into yellow lines and green lines.

2) error-correcting crystal formation: a single 'seed' crystal will grow in a spiral to form a perfect checkerboard of yellow and green tiles

3) infection and reprogramming: tiles initially assemble using the crystal-formation algorithm. then a viral tile is introduced which inserts a new program that propagates through the crystal. the crystal breaks up and the units form lines using the line-forming algorithm

4) DNA replication: a single strand (4-mer, 5-mer, etc) is introduced into a pool of free units. the DNA is exponentially replicated using an error-correcting algorithm with only local state and local message-passing - just like the real thing.

each unit is programmed with the code which contains all algorithms. then, a special 'programming' unit is used which can easily set the active algorithm and active color of each unit.