Luis Roalter

Technische Universität München | TUM · Department of Media Technology

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 practicin...

People do not always think and behave rationally. Behavioral economics has produced theories to explain when and why people make such allegedly irrational decisions, for example if it comes to spending money. However, humans tend to use reference points to judge and decide. Nowadays, mobile devices can work as flexible tools to create reference poi...

Multimodality can make (especially mobile) device interaction more efficient. Sensors and communication capabilities of modern smartphones and tablets lay the technical basis for its implementation. Still, mobile platforms do not make multimodal interaction support trivial. Building multimodal applications requires various APIs with different parad...

Prototyping is an important part in research and development of tangible user interfaces (TUIs). On the way from the idea to a working prototype, new hardware prototypes usually have to be crafted repeatedly in numerous iterations. This brings us to think about virtual prototypes that exhibit the same functionality as a real TUI, but reduce the amo...

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 i...

Prototyping is an important part in research and development of tangible user interfaces (TUIs). On the way from the idea to a working prototype, new hardware prototypes usually have to be crafted repeatedly in numerous iterations. This brings us to think about virtual prototypes that exhibit the same functionality as a real TUI, but reduce the amo...

Advances in the fields of distributed computing, wireless sensor networks, ubiquitous computing and many more have facilitated the development of a plenitude of Intelligent Environments (IE). The development processes, underlying tools and methods have however not yet been in the focus of researchers. A significant amount of time has to be spent fo...

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 ofte...

In this paper, we review the use of gameful design in the automotive domain. Outside of vehicles the automotive industry is mainly using gameful design for marketing and brand forming. For in-vehicle applications and for applications directly connected to real vehicles, the main usage scenarios of gameful design are navigation, eco-driving and driv...

Self-reporting techniques, such as data logging or a diary, are frequently used in long-term studies, but prone to subjects’ forgetfulness and other sources of inaccuracy. We conducted a six-week self-reporting study on smartphone usage in order to investigate the accuracy of self-reported information, and used logged data as ground truth to compar...

We present a novel user interface concept for indoor navigation which uses directional arrows and panorama images of decision points, such as turns, along the route. The interface supports the mental model of landmark-based navigation, can be used on- and offline, and is highly tolerant to localization inaccuracy. We evaluated the system in a real-...

We present a novel approach to authenticate and authorize a user, using her personal smartphone. The presented architecture is complemented with a proof-of-concept implementation. The implemented system architecture is based on a single sign-on solution (SSO), extended to allow the usage of the smartphone as authentication and authorization device....

The demographic change in modern societies has a significant impact on the future planning of self-determined mobility and mobility means. An optimized accessibility of the means of transportation is required, as well as their connection towards buildings and residences. These connections have to be modular and compatible to the mobility means of t...

Smartphones, as ubiquitous companions in all activities of daily living (ADLs), have also been adopted in educational contexts. Mobile applications go along with novel interfaces and ways of interaction, converging towards the vision of Ubiquitous Computing (Weiser, 1998). In this article, we provide an up-to-date overview of the demand on mobile s...

Small and lightweight components become more and more powerful, and at the same time cheaper. This enables the augmentation of physical objects with digital technology (e.g., information processing, communication). The interconnection of such ‘intelligent’ devices leads away from the classical internet of computers towards the ‘Internet of Things’....

Vision-based approaches for mobile indoor localization do not rely on the infrastructure and are therefore scalable and cheap. The particular requirements to a navigation user interface for a vision-based system, however, have not been investigated so far. Such mobile interfaces should adapt to localization accuracy, which strongly relies on distin...

With physical mobile interaction techniques, digital devices can make use of real-world objects in order to interact with them. In this paper, we evaluate and compare state-of-the-art interaction methods in an extensive survey with 149 participants and in a lab study with 16 participants regarding efficiency, utility and usability. Besides radio co...

In this paper, we present our vision of MobiliNet. MobiliNet is a user-oriented approach for optimising mobility chains with the goal of providing innovative mobility across different types of mobility providers - from personal short range battery powered mobility aids over different types of public transports (e.g. buses, short distance train netw...

We report on MobiDics, a mobile learning platform for professors, lecturers and tutors. In a survey with 100+ participants, we revealed that young, inexperienced teaching personnel at universities rarely use specific didactic methods to plan and structure courses. Such methods play an important role in learning processes since they, for example, ac...

In this paper, we describe a novel concept for motivating users to explore applications using natural user interfaces in the automotive domain. Based on prior findings, it can be very hard for users to detect opportunities of action in such systems. Additionally, traditional “did you know?” hints seem to be ignored by many users today. As a counter...

Vision-based approaches are a promising method for indoor navigation, but prototyping and evaluating them poses several challenges. These include the effort of realizing the localization component, difficulties in simulating real-world behavior and the interaction between vision-based localization and the user interface. In this paper, we report on...

Digital market places (e.g. Apple App Store, Google Play) have become the dominant platforms for the distribution of software for mobile phones. Thereby, developers can reach millions of users. However, neither of these market places today has mechanisms in place to enforce security critical updates of distributed apps. This paper investigates this...

We present GymSkill, a personal trainer for ubiquitous monitoring and assessment of physical activity using standard fitness equipment. The system records and analyzes exercises using the sensors of a personal smartphone attached to the gym equipment. Novel fine-grained activity recognition techniques based on pyramidal Principal Component Breakdow...

In this paper, we introduce the Android-based driver assistance system DriveAssist. The application allows the visualization of traffic information that originates from Vehicle-to-X (V2X) communication services as well as from central traffic services (CTSs) on the user's smartphone. Besides giving the driver an overview of the traffic around her/h...

We report on our research on GymSkill, a smartphone system for com- prehensive physical exercising support, from sensor data logging, activity recognition to on-top skill assessment, using the phones built-in sensors. In two iterations, we used principal component breakdown analysis (PCBA) and criteria-based scores for individualized and personaliz...

Our everyday life is increasingly pervaded by modern information and communication technologies. Miniaturization, reduced energy consumption, increased computer power, and many more are driving forces behind these developments. So-called ‘smart things’ can be applied everywhere -- in offices, private homes, cars, or even integrated in clothing.

"There's An App For That" but how do we actually develop them? While smartphones and tablet PCs are getting more and more popular and their application scenarios are growing, we still develop them using only a standard integrated development environment. Although context-based services and apps do, next to network connectivity, require lots of sens...

Advances in the fields of distributed computing, wireless sensor networks, ubiquitous computing and many more have facilitated the development of a plenitude of Intelligent Environments (IE). The development processes, underlying tools and methods have however not yet been in the focus of researchers. A significant amount of time has to be spent fo...

Advances in the fields of distributed computing, wireless sensor networks, ubiquitous computing and many more have facilitated the development of a plenitude of Intelligent Environments (IE). The development processes, underlying tools and methods have however not yet been in the focus of researchers. A significant amount of time has to be spent fo...

Today's computer systems are becoming more and more ubiquitous, and the increasing processing power and capabilities of modern mobile devices enable new applications and services. Integrated sensors provide new ways of how users can interact with their environment and are a basis for a wide field of context-aware services.

We introduce and define Cognitive Objects for human-robot interaction and human-computer interaction and disambiguate them against existing 'Smart Objects'. Cognitive Objects are physical real-world objects used in manipulation tasks by humans and robots. As such, they incorporate self-awareness, reduce ambiguity and uncertainty in object recogniti...

The aging society requires novel approaches to facilitate in-home services and support for ambient assisted living. The transformation of an everyday home into a supportive environment is a challenging task, as costs and necessary efforts are preventing us to change normal homes into high-tech care units. We present an alternative solution, in betw...

Interdisciplinary research from the domains of pervasive computing or ubiquitous computing, computer-human-interaction and computer science has led to the development of many intelligent environments, either on lab scale or as live in laboratories. While several middleware have been developed in this field, no standard middleware for intelligent en...

With fast proceeding demographic change, lack of qualified nursing staff and costs explosion concerning our health and welfare systems, new methods have to be developed to support elderly people in their home environment with ambient integrated and intelligent assistance/service technologies. Service units and related typologies presented in this p...

In the paper we present the conceptual idea of scalable robotic service cores for a simplified and rapid deployment of ambient assisted living environments. We situate our approach in between fully networked homes on the one hand and smart artifacts on the other end of the scale. We elaborate on the multi-dimensional interdisciplinary challenges th...