Tactilient: Turbulence resilient tactile icons for pilot feedback

Given the high attentional demand in aircraft cockpits, tactons can be used to deliver information without overloading the visual and auditory channels. However, aircraft are subject to turbulence that interfere with vibrotactile feedback. To investigate the impact of turbulence on tacton identification, 18 participants tried to identify 9 tactons with varying intensity and rhythm, while experiencing uncomfortable and very uncomfortable levels of mechanical vibration defined in ISO 2631-1. The results show that the effectiveness of tactile communication decreases with the rhythm identification performance as the level of turbulence increases. In our study, an RMS acceleration delta of 0.70 Grms between two consecutive tactons guaranteed near zero confusion. Based on their experience performing the study, participants built tactons that included 4 pulses, lasted for at least 350 ms and vibrated at no less than 1.25 Grms to be comfortably perceived. Our results will support practitioners for designing tactons that can be more resilient to turbulence.