Synchronizing asynchronous mobile robots with limited visibility using lights

Abstract

There are three models of automated robots based on their activation schedules and time notions. They are FSYNC, SSYNC and ASYNC Model. The FSYNC-fully synchronous robots have the common notion of time and follow a global round of time. In every turn, all the robots are active and perform their job in synchronization. All the robots have the same notion of time in the SSYNC-semi-synchronous model, whereas in this model, all robots may not be active in each round. The activation time of ASYNC-asynchronous is independent and unpredictable. Research is ongoing to vanish the difference between asynchrony, semi-synchrony and synchrony by equipping the robots with various combination of lights and snapshots. Most of the research has been done on robots with unlimited visibility capabilities. In these works, a robot can view the colors of all other robots and based on that the decision is taken to change its own color thus achieves synchronization. Decision taking becomes challenging if the robots have limited view of the other robots. This paper proposed a technique of synchronizing the robots which are asynchronous by nature, using observable colored lights, where the robots have limited range of visibility.