Haptic Situational Awareness Device Using Continuous Vibrotactile Sensations

Abstract

For humans interacting with their environment (such as walking in crowded or low light conditions) or operating vehicles (aircraft or cars), automated alerts and directional cues serve to guide their attention towards the priority task. Traditionally, such alerts and direction cues are provided using audio-visual channels. In fast changing situations, the human audio-visual resources can get degraded. In such situations, vibrotactile alerts and directional cues can easily grab the attention of operators. Furthermore, vibrotactile cues allow for more heads-up time. This research investigates the effects of placing a vibrotactile display on the torso for enhancing situational awareness of humans whose visual/auditory senses may be degraded. The authors describe the findings regarding placement and properties of the proposed device and assess the added effectiveness of the vibrotactile cuing method when used alone and in combination with visual-auditory sensory modalities. In pursuance of this research, a vibrotactile display worn on the torso has been developed, which consists of low-cost vibrotactile actuators that provide vibrotactile alerts and directional cues. Alerts and directional information are encoded and presented using the Funnelling Illusion. Funnelling Illusion provides perceptually more natural cues while reducing the number of actuators, thus enhancing reliability and significant reduction in weight and cost of the device. Experimental results on human volunteers indicate that vibrotactile sensations which are intuitive to perception of the user (continuous sensation instead of discrete) contribute more to enhancement of situational awareness of user during sensory distraction as compared to visual-audio cues only.