Understanding MultiRobot Systems: on the Concept of Legibility Legibility can be defined as the ability of a robot to communicate its intent to the user. Legibility is relatively little investigated in multirobot systems, but, in the literature, studies exist where the trajectory of manipulators is analyzed as a factor to improve the collaboration between robots and users. In this paper, we focus on the legibility of a group of mobile robots. To this end, we consider a set of motionvariables: trajectory, dispersion and stiffness. They are typical parameters that determine the motion of a group of robots. To analyze the effect of the motionvariables over legibility, Fisherxe2x80x99s exact test and ANOVA (analysis of variance) were carried out. The data for the statistical analysis cover a full factorial plan and they were collected in a virtual reality setup, where the users shared the environment with a group of robots. We investigate two aspects of legibility: the correctness and the rapidity of communication, namely if the communication happens correctly and how fast it happens. Trajectory was found to be relevant to correctly communicate the intention of the robots, while stiffness and dispersion were relevant for the rapidity of legibility.

Towards situational awareness from robotic group motion The control of multiple robots in the context of teleexploration tasks is often attentionally taxing, resulting in a loss of situational awareness for operators. Unmanned aerial vehicle swarms require significantly more multitasking than controlling a plane, thus making it necessary to devise intuitive feedback sources and control methods for these robots. The purpose of this article is to examine a swarmu0027s nonverbal behaviour as a possible way to increase situational awareness and reduce the operators cognitive load by soliciting intuitions about the swarmu0027s behaviour. To progress on the definition of a database of nonverbal expressions for robot swarms, we first define categories of communicative intents based on spontaneous descriptions of common swarm behaviours. The obtained typology confirms that the first two levels (as defined by Endsley: elements of environment and comprehension of the situation) can be shared through swarms motionbased communication. We then investigate group motion parameters potentially connected to these communicative intents. Results are that synchronized movement and tendency to form figures help convey meaningful information to the operator. We then discuss how this can be applied to realistic scenarios for the intuitive command of remote robotic teams.