Who’s with me? A Tactile Interface for Identification of Separation of Squad Members from their Team

Abstract

In military operations, commanders gather information in real-time from multiple sources. Their immediate communication is primarily through audio and/or visual devices. At the same time, most of their tasks rely heavily on the visual modality. Together with the need to execute tasks rapidly, cognitive overload and decreased performance may occur. It has been shown that in operational settings tactile alerts can enhance performance and improve information transfer in terms of cognitive workload and interruptions management. We aim to transfer sub-primary information to the commander via tactile alerts in order to improve awareness to accumulation of new relevant information. A field examination introduced this concept of alerts for the case of squad disconnections (separation of squad member from the team) and was aimed at providing information to commanders via visual or tactile modalities. Eighteen infantry soldiers took part in this examination. The participants were divided into three squads. Each squad consisted of one commander and 5 soldiers. All participants were military reserve soldiers who have been on active duty in the year prior to the study. Each commander wore two tactile bracelets, one on each forearm, which were used to transfer the tactile alert. The visual alerts were activated through a regular smartphone and the alert appeared visually on the phone's screen (without audio or vibration). The experiment included an urban navigation task from one waypoint to another. The duration of each experiment was 75 minutes and the pace of the navigation was set at an operational pace of 3-4 km/h. During the navigation task, the commander was required to detect targets on route and mark them on a map and at same time to ensure that there are no separations between squad members. The route was split into three sections: in the first section the commander received tactile alerts for disconnection, in the second section he received visual alerts and the third section was a baseline condition with no alerts. The third section simulated the current and common practice in armies today. The experimental findings focused on commanders' performance: navigation abilities, and target detection and response time to the separation/cutoff events. Each one of the commanders had one navigation error, i.e., wrong turn. For each one of the three participants, this error occurred in the visual alert condition, i.e. when they received alerts through the visual interface. With regards to target detection, the experimental results indicated a slight advantage for the tactile alerts condition (with a 73% success rate) compared to visual alerts or the baseline condition (with an average of 67% success for both cases). Regarding the response time to the separation/cutoff events, all three commanders identified and reported all 9 disconnection events that occurred during their experiment, which is quite expected as they are experienced Infantry commanders. A linear mixed model (LMM) was used on the log of the response time. The time until detection of disconnection with tactile alerts was approximately 9 times shorter than the detection time in the case of visual alerts and no alerts. Although the visual display condition had no significant statistical difference than the baseline, shorter response times were seen in the visual condition section. Results revealed that using tactile alerts during a mission decreased commanders’ response time to mission critical events compared to visual alerts or no alerts. Commanders' subjective opinions of tactile devices were highly supportive. Future research should include the effect of integration of tactile alerts and tactile communications on commanders and soldiers in operational environments.