
The paper details the first successful attempt at using model-checking techniques to verify the correctness of distributed algorithms for robots evolving in a \emph{continuous} environment. The study focuses on the problem of rendezvous of two robots with lights. There exist many different rendezvous algorithms that aim at finding the minimal number of colors needed to solve rendezvous in various synchrony models (e.g., FSYNC, SSYNC, ASYNC). While these rendezvous algorithms are typically very simple, their analysis and proof of correctness tend to be extremely complex, tedious, and error-prone as impossibility results are based on subtle interactions between robots activation schedules. The paper presents a generic verification model written for the SPIN model-checker. In particular, we explain the subtle design decisions that allow to keep the search space finite and tractable, as well as prove several important theorems that support them. As a sanity check, we use the model to verify several known rendezvous algorithms in six different models of synchrony. In each case, we find that the results obtained from the model-checker are consistent with the results known in the literature. The model-checker outputs a counter-example execution in every case that is known to fail. In the course of developing and proving the validity of the model, we identified several fundamental theorems, including the ability for a well chosen algorithm and ASYNC scheduler to produce an emerging property of memory in a system of oblivious mobile robots, and why it is not a problem for luminous rendezvous algorithms.
FOS: Computer and information sciences, Model checking, Rendezvous, Asynchrony, [INFO.INFO-RB] Computer Science [cs]/Robotics [cs.RO], Verification, [INFO.INFO-DS] Computer Science [cs]/Data Structures and Algorithms [cs.DS], [INFO] Computer Science [cs], Autonomous mobile robots, [INFO.INFO-DM] Computer Science [cs]/Discrete Mathematics [cs.DM], [INFO.INFO-MC] Computer Science [cs]/Mobile Computing, [INFO.INFO-CG] Computer Science [cs]/Computational Geometry [cs.CG], Computer Science - Distributed, Parallel, and Cluster Computing, Continuous space, [INFO.INFO-DC] Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC], [INFO.INFO-CC] Computer Science [cs]/Computational Complexity [cs.CC], Lights, Computer Science - Multiagent Systems, Distributed, Parallel, and Cluster Computing (cs.DC), [INFO.INFO-FL] Computer Science [cs]/Formal Languages and Automata Theory [cs.FL], Multiagent Systems (cs.MA)
FOS: Computer and information sciences, Model checking, Rendezvous, Asynchrony, [INFO.INFO-RB] Computer Science [cs]/Robotics [cs.RO], Verification, [INFO.INFO-DS] Computer Science [cs]/Data Structures and Algorithms [cs.DS], [INFO] Computer Science [cs], Autonomous mobile robots, [INFO.INFO-DM] Computer Science [cs]/Discrete Mathematics [cs.DM], [INFO.INFO-MC] Computer Science [cs]/Mobile Computing, [INFO.INFO-CG] Computer Science [cs]/Computational Geometry [cs.CG], Computer Science - Distributed, Parallel, and Cluster Computing, Continuous space, [INFO.INFO-DC] Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC], [INFO.INFO-CC] Computer Science [cs]/Computational Complexity [cs.CC], Lights, Computer Science - Multiagent Systems, Distributed, Parallel, and Cluster Computing (cs.DC), [INFO.INFO-FL] Computer Science [cs]/Formal Languages and Automata Theory [cs.FL], Multiagent Systems (cs.MA)
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| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Top 10% |
