D. Harris (Ed.): EPCE/HCII 2013, Part II, LNAI 8020, pp. 12–18, 2013. © Springer-Verlag Berlin Heidelberg 2013 Comprehension of Vibrotactile Route Guidance Cues Andre Garcia 1 , Jesse Eisert 1 , Carryl L. Baldwin 1 , and Victor Finomore 2 1 Department of Psychology, George Mason University, United States 2 Human Effectivness / Battlespace Acoustics Branch, Air Force Research Lab, United States agarciagmu@gmail.com, {jeisert,cbaldwi4}@gmu.edu, victor.finomore@wpafb.af.mil Abstract. Two experiments with 24 participants each evaluated comprehension of vibrotactile route guidance instructions via a tactile seat in a driving simula- tor. Vibrotactile patterns were presented from an array of 8 tactors arranged in two rows of 4 tactors located in the seat pan. A faster pulse rate and a slower pulse rate as well as four distinct locations on the tactile seat (Front-Left, Front- Right, Back-Left, Back-Right) created 8 different combinations of stimuli. Across all participants, the most consistent interpretation was that the faster pulse rate played from the back two tactors was perceived as an instruction to make the next most immediate turn while a slow pulse rate from the front two tactors was interpreted as a cue directing the user to the direction of the next eventual turn. Results have direct implications for design of effective vibrotac- tile and multimodal route guidance systems. 1 Introduction Vibrotactile technology for in-vehicle use has shown increasing promise and popu- larity of late (Scott & Gray, 2008; Mohebbi, Gray, Tan, 2009). General Motors cur- rently offers a feature on their Cadillac XTS sedan where the seat pan vibrates if there is a potential rear-end collision while you are reversing. This is just one example among several other current production vehicles that come equipped with vibrotactile technology. The tactile modality offers a way to relay information that is privileged to only the user. Tactile collision warning systems have been shown to effectively re- duce reaction time (Scott and Gray, 2008), and may be particularly effective in mul- timodal systems (Mohebbi, Gray, & Tan, 2009). The tactile modality is a way to provide the user information without relying on visual or auditory attentional resources that are often in high demand in many opera- tional settings. Recent studies investigating vibrotactile route guidance systems have shown great potential. Van Erp and Van Veen (2004) demonstrated how a tactile navigation system display can reduce a driver’s perceived workload compared to a visual display, particularly in high workload settings. Van Erp, Van Veen, Jansen, and Dobbins (2006) investigated the efficacy and feasibility of a tactile navigation waist belt and found that directional information is easy, intuitive, and requires almost no training, although their results on how to map distance were inconclusive. Vibrotactile systems for in-vehicle technology have generally been limited to collision warning