Identification rate of simple and complex tactile alerts in mum-t setup

Vibro-tactile interfaces were proposed as an alternative to enhance human-machine communication in information-rich domains. The current study aims to examine the effectiveness of two levels of tactile alerts when combined with visual alerts, in MUM-T (Manned UnManned Teaming) setup. In MUM-T, aside from their primary mission, mounted operators are responsible for supportive unmanned systems and must attend to their health. On the simple level, the alert provides information about a threat or a failure in the supportive unmanned systems, while in the complex level, the alert includes more specific information about the source of failure, that may require more effort to interpret. The experiment simulates an operational mission in which participants ride an autonomous ground patrol vehicle while identifying threats and targets in the area and being supported by two unmanned systems. Response accuracy to alerts and threat identification rates were measured. Results indicate that tactile alerts given in addition to visual alerts in a visually loaded and auditory noisy scene, improve task performance. Moreover, the complex level of tactile alerts did not impair performance compared to the simple level of tactile alerts and led to higher rate of identification in specific cases. Nevertheless, relatively high rates of false alarms (FA) for threats were observed, especially when tactile alerts were present, which can be explained by the payment matrix (no penalty) or by the assumption that adding tactile alerts may lead participants to be more vigilant, which can lead to higher correct identifications, but also to higher FA rates.