Investigating the Rate of Failure of Asynchronous Gathering in a Swarm of Fat Robots with Limited Visibility

In the present paper we investigate the failure probability of the asynchronous gathering task in a mobile robot swarm that contains weak robots (oblivious, with limited visibility, without global navigation and communication). We are modelling fat robots, which are represented as solid discs. We performed numerous computer simulations in order to measure the rate of failure of gathering using extended Ando’s gathering algorithm [1]. The physical parameters of the simulations are based on our previous experiments on image processing based kin recognition method using Surveyor SRV-1 robots [11] [12]. It was obtained that the computational time and the travelling speed of the robots affect very strongly the rate of gathering success. If we apply SRV-1 robots with the referred kin recognition method and highest possible travelling speed, then the rate of failure is very close to 100 percent. While, reducing the travelling speed with a factor of 1/20 (or increasing the computational performance to 20 times the original) results in much better success rates of gathering. Besides, we have found that the failure rate increases together with the number of robots.