Marion Koelle

Don't look at me that way!: Understanding User Attitudes Towards Data Glasses Usage

Data glasses do carry promising potential for hands-free interaction, but also raise various concerns amongst their potential users. In order to gain insights into the nature of those concerns, we investigate how potential usage scenarios are perceived by device users and their peers. We present results of a two-step approach: a focus group discussion with 7 participants, and a user study with 38 participants. In particular, we look into differences between the usage of data glasses and more established devices such as smart phones. We provide quantitative measures for scenario-related social acceptability and point out factors that can influence user attitudes. Based on our quantitative and qualitative results, we derive design implications that might support the development of head-worn devices and applications with an improved social acceptability.

Experimental evaluation of user interfaces for visual indoor navigation

Mobile location recognition by capturing images of the environment (visual localization) is a promising technique for indoor navigation in arbitrary surroundings. However, it has barely been investigated so far how the user interface (UI) can cope with the challenges of the vision-based localization technique, such as varying quality of the query images. We implemented a novel UI for visual localization, consisting of Virtual Reality (VR) and Augmented Reality (AR) views that actively communicate and ensure localization accuracy. If necessary, the system encourages the user to point the smartphone at distinctive regions to improve localization quality. We evaluated the UI in a experimental navigation task with a prototype, informed by initial evaluation results using design mockups. We found that VR can contribute to efficient and effective indoor navigation even at unreliable location and orientation accuracy. We discuss identified challenges and share lessons learned as recommendations for future work.

Joint Estimation of 3D Hand Position and Gestures from Monocular Video for Mobile Interaction

We present a machine learning technique to recognize gestures and estimate metric depth of hands for 3D interaction, relying only on monocular RGB video input. We aim to enable spatial interaction with small, body-worn devices where rich 3D input is desired but the usage of conventional depth sensors is prohibitive due to their power consumption and size. We propose a hybrid classification-regression approach to learn and predict a mapping of RGB colors to absolute, metric depth in real time. We also classify distinct hand gestures, allowing for a variety of 3D interactions. We demonstrate our technique with three mobile interaction scenarios and evaluate the method quantitatively and qualitatively.

SmartPiggy: a piggy bank that talks to your smartphone

Saving money is usually a tedious task that requires a high degree of self-control for many of us. Some people have one or more specific savings targets in mind and thus need to prioritize them. We propose connecting a savings box with a personal smartphone. Thus, people become motivated to keep track of their savings for multiple targets. Using a savings box capable of counting money and connecting it to an app, we believe people stick to their plans to save with higher motivation and are happier with their behavior. In this paper, we present first evidence for the success of this concept. We gathered feedback through an online user study in which participants were shown a video prototype. We propose further research directions with our SmartPiggy, to confirm the feasibility of behavioral economics in HCI.

Gamification-supported Exploration and Practicing for Automotive User Interfaces and Vehicle Functions

When driving an unknown car, the interaction with its user interfaces and the operation of (comfort) vehicle functions can be very challenging and thus cause safety concerns. However, this problem can be overcome already with a short learning and practicing phase. For this reason, we analyze the potential of gamification for exploring and practicing the use of automotive user interfaces and vehicle functions. Based on the analysis of available examples, we have created a gamified automotive exploration and practicing framework. The framework allows exploring vehicle functions and user interfaces in real vehicles as well as in applications for mobile devices. By reflecting on the results of a first user study with the framework, we deliver a set of guidelines for designing and evaluating gamified applications for the automotive domain, which can serve as a support for future developments.

Visual authentication: a secure single step authentication for user authorization

User authentication on publicly exposed terminals with established mechanisms, such as typing the credentials on a virtual keyboard, can be insecure e.g. due to shoulder surfing or due to a hacked terminal. In addition, username and password entry can be time-consuming and thus improvable with relation to usability. As security and comfort are often competing with each other, novel authentication and authorization methods especially for public terminals are desirable. In this paper, we present an approach on a distributed authentication and authorization system, where the user can be easily identified and enabled to use a service with his smartphone. The smartphone (as personal and private device the user is always in control of) can provide a highly secure authentication token that is renewed and exchanged in the background without the users participation. The claimed improvements were supported by a user survey with an implementation of a digital room management system as an example for a public display. The proposed authentication procedure would increase security and yet enable fast authentication within publicly exposed terminals.

Only play in your comfort zone: interaction methods for improving security awareness on mobile devices

Abstract In this paper, we study the concept of security zones as an intermediate layer of compartmentalization on mobile devices. Each of these security zones is isolated against the other zones and holds a different set of applications and associated user data and may apply different security policies. From a user point of view, they represent different contexts of use for the device, e.g., to distinguish between gaming (private context), payment transactions (secure context), and company-related email (enterprise context). We propose multiple visualization methods for conveying the current security zone information to the user, and interaction methods for switching between zones. Based on an online and a laboratory user study, we evaluated these concepts from a usability point of view. One important result is that in the tension field between security and usability, additional hardware can support the user’s awareness toward their zone context.

Putting books back on the shelf: situated interactions with digital book collections on smartphones

We consider the reasons why we organise books in a physical environment and investigate whether situating interactions with a smartphone could improve the user experience of e-readers. Our prototype uses the Kinect depth sensor to detect the position of a user in relation to sections of a physical bookshelf. We also built a mobile application that allows users to browse and organise digital books by moving between each section. We present our initial observations of a user study that evaluated search and categorisation tasks with our prototype. Our findings motivate reasons to explore digital books in a physical environment and indicate issues to consider when designing situated interactions with e-readers.

The mind behind the glass: human factors in the design of collaborative AR environments

Immersive AR environments are situated information spaces that employ the Augmented Reality display paradigm. They tightly couple abstract, digital information and physical elements present in the users real-world environment. As a consequence of this mixed digital-physical spatiality, interface design has the chance to build upon the users cognitive map (spatial mental model) of her environment. The proposed PhD project investigates how knowledge about a users spatial mental model of an augmented scene can be translated to best practices in the design of remotely shared AR environments.

Mobile AgeCI: Potential Challenges in the Development and Evaluation of Mobile Applications for Elderly People

Designing mobile applications for elderly users can be very challenging. Their heterogeneous prior knowledge and abilities make user-centered design processes difficult. For that reasons, some measures are necessary to make the applications usable the majority of elderly people and to get useful feedback during the evaluation. In this paper, we summarize central challenges we faced during the user-centered development of a mobile fitness application for seniors. We address differences in interaction, trust issues, fears, functional complexity, and aspects of motivation. Based on these experiences, we present suggestions that can be useful for the future development and evaluation of mobile (fitness) applications for elderly people.