electronics Article A Proposal of Accessibility Guidelines for Human-Robot Interaction Malak Qbilat 1,* , Ana Iglesias 1,* and Tony Belpaeme 2 1 Department of Computer Science and Engineering, Universidad Carlos III de Madrid, 28911 Leganés, Spain 2 IDLab—imec, Ghent University, 9052 Ghent, Belgium; [email protected] * Correspondence: [email protected] (M.Q.); [email protected] (A.I.) Abstract: We will increasingly become dependent on automation to support our manufacturing and daily living, and robots are likely to take an important place in this. Unfortunately, currently not all the robots are accessible for all users. This is due to the different characteristics of users, as users with visual, hearing, motor or cognitive disabilities were not considered during the design, implementation or interaction phase, causing accessibility barriers to users who have limitations. This research presents a proposal for accessibility guidelines for human-robot interaction (HRI). The guidelines have been evaluated by seventeen HRI designers and/or developers. A questionnaire of nine five-point Likert Scale questions and 6 open-ended questions was developed to evaluate the proposed guidelines for developers and designers, in terms of four main factors: usability, social acceptance, user experience and social impact. The questions act as indicators for each factor. The majority (15 of 17 participants) agreed that the guidelines are helpful for them to design and implement accessible robot interfaces and applications. Some of them had considered some ad hoc guidelines in their design practice, but none of them showed awareness of or had applied all the proposed guidelines in their design practice, 72% of the proposed guidelines have been applied by less than or equal to 8 participants for each guideline. Moreover, 16 of 17 participants would use the Citation: Qbilat, M.; Iglesias, A.; proposed guidelines in their future robot designs or evaluation. The participants recommended the Belpaeme, T. A Proposal of importance of aligning the proposed guidelines with safety requirements, environment of interaction Accessibility Guidelines for (indoor or outdoor), cost and users’ expectations. Human-Robot Interaction. Electronics 2021, 10, 561. https://doi.org/ Keywords: accessibility; guidelines; human-robot interaction; inclusive design 10.3390/electronics10050561 Academic Editor: George A. Tsihrintzis 1. Introduction Diversity in technology has become pervasive in everyday life. Robot designers and Received: 22 December 2020 Accepted: 30 January 2021 developers must also consider in their designs and products a wide range of potential users Published: 27 February 2021 with a great diversity of abilities and needs. Implementing accessible robots requires a deep knowledge of interaction barriers that people could face when using each robot component, Publisher’s Note: MDPI stays neutral depending on their interaction characteristics, abilities and capabilities. However, most of with regard to jurisdictional claims in the HRI designers and developers have limited awareness of accessibility issues, and a tool published maps and institutional affil- for helping them to apply this knowledge in their designs and implementations would iations. be useful. That is why in this paper we propose a set of accessibility guidelines, to help human-robot interaction designers and developers to construct accessible robots for all. 2. Related Work 2.1. Socially Assistive Robotics Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. Accessibility guidelines that are evaluated in this research, mainly focus on socially This article is an open access article assistive robotics. Socially assistive robotics (SAR) refer to robotics that present services distributed under the terms and to the users through social instead of physical interaction [1]. Assistive robots with social conditions of the Creative Commons abilities are categorized into two types (services robots and companion robots), and it Attribution (CC BY) license (https:// is difficult to classify most robots into one of these two categories, as the robot can be creativecommons.org/licenses/by/ implemented to both provide services and companionship [2]. 4.0/). Electronics 2021, 10, 561. https://doi.org/10.3390/electronics10050561 https://www.mdpi.com/journal/electronics ElectronicsElectronics 2021 2021, 10, ,10 561, 561 2 of2 of14 14 Electronics 2021, 10, 561 2 of 13 abilitiesabilities are are categorized categorized into into two two types types (services (services robots robots and and companion companion robots), robots), and and it itis is difficultdifficult to to classify classify most most robots robots into into one one of of these these two two categories, categories, as as the the robot robot can can be be imple- imple- mentedmented to to both both prov provideide services services and and companionship companionship [2] [2]. 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