The haptic properties of textile interfaces support eyes-free use well. However, user interfaces often require composing many controls, which complicates orientation by palpation. We investigated three composition concepts that combine textile components in different ways, using a sample smart home scenario: One uses the select-and-control flow of universal remotes, one resembles the users’ environment, and one divides the interface into application sections. Of the latter, we also created a spacious variant to observe the effect of blank space between interface regions. We first explored how well users understand those composition concepts when first using the interface eyes-free. After familiarization, we measured input performance and preferences. We found task completion times much faster than expected from previous recognition studies. While performance was similar for most interfaces, the select-and-control flow was slower, but participants preferred it after familiarization. From our findings, we derive design recommendations for compound textile UIs and individual components.

Textile surfaces, such as on sofas, cushions, and clothes, offer promising alternative locations to place controls for digital devices. Textiles are a natural, even abundant part of living spaces, and support unobtrusive input. While there is solid work on technical implementations of textile interfaces, there is little guidance regarding their design—especially their haptic cues, which are essential for eyes-free use. In particular, icons easily communicate information visually in a compact fashion, but it is unclear how to adapt them to the haptics-centric textile interface experience. Therefore, we investigated the recognizability of 84 haptic icons on fabrics. Each combines a shape, height profile (raised, recessed, or flat), and affected area (filled or outline). Our participants clearly preferred raised icons, and identified them with the highest accuracy and at competitive speeds. We also provide insights into icons that look very different, but are hard to distinguish via touch alone.

Textile interfaces enable designers to integrate unobtrusive media and smart home controls into furniture such as sofas. While the technical aspects of such controllers have been the subject of numerous research projects, the physical form factor of these controls has received little attention so far. This work investigates how general design properties, such as overall slider shape, raised vs. recessed sliders, and number and layout of tick marks, affect users’ preferences and performance. Our first user study identified a preference for certain design combinations, such as recessed, closed-shaped sliders. Our second user study included performance measurements on variations of the preferred designs from study 1, and took a closer look at tick marks. Tick marks supported orientation better than slider shape. Sliders with at least three tick marks were preferred, and performed well. Non-uniform, equally distributed tick marks reduced the movements users needed to orient themselves on the slider.

Adding a mid-air pen to Handheld Augmented Reality creates a new kind of bimanual interaction for which many fundamental interaction design questions have not been answered yet. In particular, menus are an essential component in most visual interfaces, but it is unclear how to best interact with them in this setting: using the pen in mid-air or on a surface, using the touchscreen, or by moving the smartphone itself. We compared basic menus for these methods by analyzing success rates, selection times, device movement, and subjective ratings. Our results indicate that interacting with a mid-air menu using the pen, and operating a menu with the hand holding the smartphone, are sufficiently competitive to the current standard of two-handed touchscreen interaction, so that interaction designers can freely choose among them based on the interaction context of their application.

Modeling in Augmented Reality (AR) lets users create and manipulate virtual objects in mid-air that are aligned to their real environment. We present ARPen, a bimanual input technique for AR modeling that combines a standard smartphone with a 3D-printed pen. Users sketch with the pen in mid-air, while holding their smartphone in the other hand to see the virtual pen traces in the live camera image. ARPen combines the pen's higher 3D input precision with the rich interactive capabilities of the smartphone touchscreen. We studied subjective preferences for this bimanual input technique, such as how people hold the smartphone while drawing, and analyzed the performance of different bimanual techniques for selecting and moving virtual objects. Users preferred a bimanual technique casting a ray through the pen tip for both selection and translation. We provide initial design guidelines for this new class of bimanual AR modeling systems.