Understanding the Uncanny: Both Atypical Features and Category Ambiguity Provoke Aversion toward Humanlike Robots

Abstract

Robots intended for social contexts are often designed with explicit humanlike attributes in order to facilitate their reception by (and communication with) people. However, observation of an “uncanny valley”—a phenomenon in which highly humanlike entities provoke aversion in human observers—has lead some to caution against this practice. Both of these contrasting perspectives on the anthropomorphic design of social robots find some support in empirical investigations to date. Yet, owing to outstanding empirical limitations and theoretical disputes, the uncanny valley and its implications for human-robot interaction remains poorly understood. We thus explored the relationship between human similarity and people's aversion toward humanlike robots via manipulation of the agents' appearances. To that end, we employed a picture-viewing task (Nagents = 60) to conduct an experimental test (Nparticipants = 72) of the uncanny valley's existence and the visual features that cause certain humanlike robots to be unnerving. Across the levels of human similarity, we further manipulated agent appearance on two dimensions, typicality (prototypic, atypical, and ambiguous) and agent identity (robot, person), and measured participants' aversion using both subjective and behavioral indices. Our findings were as follows: (1) Further substantiating its existence, the data show a clear and consistent uncanny valley in the current design space of humanoid robots. (2) Both category ambiguity, and more so, atypicalities provoke aversive responding, thus shedding light on the visual factors that drive people's discomfort. (3) Use of the Negative Attitudes toward Robots Scale did not reveal any significant relationships between people's pre-existing attitudes toward humanlike robots and their aversive responding—suggesting positive exposure and/or additional experience with robots is unlikely to affect the occurrence of an uncanny valley effect in humanoid robotics. This work furthers our understanding of both the uncanny valley, as well as the visual factors that contribute to an agent's uncanniness.

Frequency of Switching Touching Mode Reflects Tactile Preference Judgment

“…www.nature.com/scientificreports www.nature.com/scientificreports/ pleasant, possibly because these stimuli are difficult to categorize [24][25][26][27] . When this is also true for tactile domain, ambiguous tactile stimuli also make participants feel unfavorable toward them and would induce the use of combinations of different touching modes to accumulate more detailed information about them.…”

Pupillary Responses to Robotic and Human Emotions: The Uncanny Valley and Media Equation Confirmed

“…Although the evidence is limited ( Gee et al, 2005 ), several studies have examined qualitative uncanniness ratings about robotic or virtual characters with varying realistic and naturalistic appearances and found a pattern in line with the uncanny valley as depicted in Figure 1A (e.g., Dill et al, 2012 ; Piwek et al, 2014 ; Mathur and Reichling, 2016 ; Strait et al, 2017 ). These findings have had considerable impact on the field of robotic design as they mean that near human-looking robots may evoke undesired, negative, affective responses ( Vinayagamoorthy et al, 2005 ).…”

Human-Like Arm Motion Generation: A Review

“…Robotic manipulators and, in second place, humanoids are arguably the most preferred tool for testing and showing the level of human-likeness provided by different generation techniques. A humanoid robot can provide a high level of anthropomorphism that can be used to encourage interactions with human partners [16,17]. Figure 4 shows the anthropomorphic robotic systems that were utilized in the included studies.…”