Multimodal feedback for teleoperation of multiple mobile robots in an outdoor environment

Better situational awareness helps understand remote environments and achieve better performance in the teleoperation of multiple mobile robots (e.g., a group of unmanned aerial vehicles). Visual and force feedbacks are the most common ways of perceiving the environments accurately and effectively; however, accurate and adequate sensors for global localization are impractical in outdoor environments. Lack of this information hinders situational awareness and operating performance. In this paper, a visual and force feedback method is proposed for enhancing the situational awareness of human operators in outdoor multi-robot teleoperation. Using only the robots' local information, the global view is fabricated from individual local views, and force feedback is determined by the velocity of individual units. The proposed feedback method is evaluated via two psychophysical experiments: maneuvering and searching tests using a human/hardware-in-the-loop system with simulated environments. In the tests, several quantitative measures are also proposed to assess the human operator's maneuverability and situational awareness. Results of the two experiments show that the proposed multimodal feedback enhances only situational awareness of the operator.