The agreement power of disagreement.

We consider the rendezvous problem of two autonomous robots with very weak capacities. This problem is notoriously impossible to solve in the semi-synchronous execution model when robots are deterministic, oblivious, and their ego-centered coordinate system is fully symmetric. We show that if the robots disagree on the unit distance of their coordinate system, it becomes possible to solve rendezvous and agree on a final common location, without additional assumptions. We also generalize our scheme to solve gathering (that is, rendezvous of n ≥ 2 robots) in the same setting, possibly starting from a bivalent configuration. • We introduce new techniques that take advantage of different unit distances. • We design and prove a solution to the rendezvous problem of oblivious and disoriented robots in SSYNC. • We generalize our design to solve gathering from any arbitrary initial configuration. [ABSTRACT FROM AUTHOR]