Give me the control, I can see the robot!

Emergency and exploration missions are accomplished by remote stationary personnel and on-site responders that can deploy robots for dealing with situations involving hazard or inaccessibility. Thus, human-robot interaction (HRI) plays a key role in these kinds of applications. Intra-scenario operator mobility is often considered to be advantageous for acquiring situational awareness (SA) in the context of robot teleoperation, but non portable devices can provide a greater volume of processed information. This should not be discounted when trying to build more effective human-robot interaction (HRI) in search and rescue (SAR) or exploration missions. In this paper, we report a set of experiments comparing a desktop-based interface with a PDA-based interface for remote control of mobile robots. Our goal is twofold. First we aim at defining which kinds of operators have the best SA under different conditions. Second, we investigate a control transfer policy for determining when an operator should hand over to another, depending on the device, the task and the context.