Assessing the scalability of a multiple robot interface

As multiple robot systems become more common, it is necessary to develop scalable human-robot interfaces that permit the inclusion of additional robots without reducing the overall system performance. Workload and situational awareness play key roles in determining the ratio of m operators to n robots. A scalable interface, where m is much smaller than n, will have to manage the operator´s workload and promote a high level of situation awareness. This work focused on the development of a scalable interface for a single human-multiple robot system. This interface introduces a relational “halo” display that augments a camera view to promote situational awareness and the management of multiple robots by providing information regarding the robots´ relative locations with respect to a selected robot. An evaluation was conducted to determine the scalability of the interface focusing on the effects of increasing the number of robots on workload, situation awareness, and robot usage. Twenty participants completed two bomb defusing tasks: one employing six robots, the other nine. The results indicated that increasing the number of robots increased overall workload and the operator´s situation awareness.