Howel: A Soft Wearable with Dynamic Textile Patterns as an Ambient Display for Cardio Training Çağlar Genç Yavuz Ali Ekmekçioğlu Koç University – Arçelik Research Center for Creative Industries, 34450, İstanbul, Turkey cgenc14@ku.edu.tr yekmekcioglu14@ku.edu.tr Fuat Balcı Timing and Decision-Making Laboratory and Research Center for Translational Medicine, Koç University, 34450, İstanbul, Turkey fbalci@ku.edu.tr Hakan Ürey Optical Microsystems Laboratory Koç University, 34450, İstanbul, Turkey hurey@ku.edu.tr Oğuzhan Özcan Koç University – Arçelik Research Center for Creative Industries, 34450, İstanbul, Turkey oozcan@ku.edu.tr ABSTRACT 1 In-situ exploration of heart rate (HR) zones during cardio training (CT) is important for training efficiency. However, approaches for monitoring HR, either depend on complex visualizations on small screens (i.e., smartwatches) or intrusive modalities (i.e. haptic, auditory) that might force the attention to the information. We developed an early prototype, Howel, a novel wrist-worn soft wearable to display HR zone information during CT. Our concept utilizes mapping information onto dynamic patterns (color changing stripes) as an easy-to-understand ambient display. To preserve non-intrusiveness, it uses non-emissive modality by heating thermochromic paints on its textile surfaces. Early feedback from three participants suggests that soft wearables with non- emissive dynamic patterns have potential (1) to embed information organically on the body, (2) to Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for third-party components of this work must be honored. For all other uses, contact the Owner/Author. CHI'19 Extended Abstracts, May 4–9, 2019, Glasgow, Scotland Uk © 2019 Copyright is held by the owner/author(s). ACM ISBN 978-1-4503-5971-9/19/05. https://doi.org/10.1145/3290607.3312857