Programming Claytronics with Meld

Meld is a programming language designed for robustly programming massive ensembles. Meld was designed to give the programmer an ensemble-centric viewpoint, where they write a program for an ensemble rather than the modules that make it up. A program is then compiled into individual programs for the nodes that make up the ensemble. In this way the programmer need not worry about the details of programming a distributed system and can focus on the logic of their program.

Because Meld is a declarative programming language (specifically, a logic programming language), the programs written in Meld are concise. Both the localization algorithm and the metamodule planning algorithms (papers linked below) are implemented in Meld in only a few pages of code. Because the implementations are so concise, we've found it practical to prove them correct. We have proved correctness of the metamodule planning algorithm as written in Meld. We found this proof to be easier to carry out than a proof on psuedo code.

Furthermore, these implementations are inherently fault-tolerant. They can recover from modules that experience FAIL-STOP errors as the Meld runtime automatically recovers from these errors without any need for the programmer to think about them. Between the ability to perform proofs directly on Meld code and the inherent fault-tolerance provided by the runtime, Meld programs are robust. They have been demonstrated on ensembles containing millions of modules, as shown in the video on the right.

Publications and Documents