Benjamin Poppinga

Gesture recognition with a Wii controller

In many applications today user interaction is moving away from mouse and pens and is becoming pervasive and much more physical and tangible. New emerging interaction technologies allow developing and experimenting with new interaction methods on the long way to providing intuitive human computer interaction. In this paper, we aim at recognizing gestures to interact with an application and present the design and evaluation of our sensor-based gesture recognition. As input device we employ the Wii-controller (Wiimote) which recently gained much attention world wide. We use the Wiimotes acceleration sensor independent of the gaming console for gesture recognition. The system allows the training of arbitrary gestures by users which can then be recalled for interacting with systems like photo browsing on a home TV. The developed library exploits Wii-sensor data and employs a hidden Markov model for training and recognizing user-chosen gestures. Our evaluation shows that we can already recognize gestures with a small number of training samples. In addition to the gesture recognition we also present our experiences with the Wii-controller and the implementation of the gesture recognition. The system forms the basis for our ongoing work on multimodal intuitive media browsing and are available to other researchers in the field.

TouchOver map: audio-tactile exploration of interactive maps

This article reports on a preliminary study, which investigates if vibration and speech feedback can be used in order to make a digital map on a touch screen device more accessible. We test if vibration feedback combined with speech, triggered as the finger moves over relevant map objects, works to make sense of the map content. The study results indicate that it is indeed possible to get a basic overview of the map layout even if a person does not have access to the visual presentation. In the conclusions the interaction problems are indentified and suggestions for future improvements are given.

My App is an Experiment: Experience from User Studies in Mobile App Stores

Experiments are a cornerstone of HCI research. Mobile distribution channels such as Apples App Store and Googles Android Market have created the opportunity to bring experiments to the end user. Hardly any experience exists on how to conduct such experiments successfully. This article reports on five experiments that were conducted by publishing Apps in the Android Market. The Apps are freely available and have been installed more than 30,000 times. The outcomes of the experiments range from failure to valuable insights. Based on these outcomes, the authors identified factors that account for the success of experiments using mobile application stores. When generalizing findings it must be considered that smartphone users are a non-representative sample of the worlds population. Most participants can be obtained by informing users about the study when the App had been started for the first time. Because Apps are often used for a short time only, data should be collected as early as possible. To collect valuable qualitative feedback other channels than user comments and email have to be used. Finally, the interpretation of collected data has to consider unpredicted usage patterns to provide valid conclusions.

Sensor-Based Identification of Opportune Moments for Triggering Notifications

Todays smartphones will issue a notification immediately after an event occurs, repeating unanswered notifications in fixed time intervals. The disadvantage of this issue-and-repeat strategy is that notifications can appear in inconvenient situations and thus are perceived as annoying and interrupting. The authors study the mobile context as inferred through a phones sensors for both answered and ignored notifications. They conducted a large-scale, longitudinal study via the Google Play store and observed 6,581 notifications from 79 different users over 76 days. Their derived model can predict opportune moments to issue notifications with approximately 77 percent accuracy. Their findings could lead to intelligent strategies to issue unobtrusive notifications on todays smartphones at no extra cost. This article is part of a special issue on managing attention.

PocketNavigator: studying tactile navigation systems in-situ

In this paper, we report about a large-scale in-situ study of tactile feedback for pedestrian navigation systems. Recent advances in smartphone technology have enabled a number of interaction techniques for smartphone that use tactile feedback to deliver navigation information. The aim is to enable eyes-free usage and avoid distracting the user from the environment. Field studies where participants had to fulfill given navigation tasks, have found these techniques to be efficient and beneficial in terms of distraction. But it is not yet clear whether these findings will replicate in in-situ usage. We, therefore, developed a Google Maps-like navigation application that incorporates interaction techniques proposed in previous work. The application was published for free on the Android Market and so people were able to use it as a navigation system in their everyday life. The data collected through anonymous monitoring suggests that tactile feedback is successfully adopted in one third of all trips and has positive effects on the users level of distraction.

Tacticycle: supporting exploratory bicycle trips

Going on excursions to explore unfamiliar environments by bike is a popular activity in many places in this world. To investigate the nature of exploratory bicycle trips, we studied tourists on their excursions on a famous vacation island. We found that existing navigation systems are either not helpful or discourage exploration. We therefore propose Tacticycle, a conceptual prototype of a user interface for a bicycle navigation system. Relying on a minimal set of navigation cues, it helps staying oriented while supporting spontaneous navigation and exploration at the same time. In cooperation with a bike rental, we rented the Tacticycle prototype to tourists who took it on their actual excursions. The results show that they always felt oriented and encouraged to playfully explore the island, providing a rich, yet relaxed travel experience. On the basis of these findings, we argue that exploratory trips can be very well supported by providing minimal navigation cues only.

6th senses for everyone!: the value of multimodal feedback in handheld navigation aids

One of the bottlenecks in todays pedestrian navigation system is to communicate the navigation instructions in an efficient but non-distracting way. Previous work has suggested tactile feedback as solution, but it is not yet clear how it should be integrated into handheld navigation systems to improve efficiency and reduce distraction. In this paper we investigate augmenting and replacing a state of the art pedestrian navigation system with tactile navigation instructions. In a field study in a lively city centre 21 participants had to reach given destinations by the means of tactile, visual or multimodal navigation instructions. In the tactile and multimodal conditions, the handheld device created vibration patterns indicating the direction of the next waypoint. Like a sixth sense it constantly gave the user an idea of how the route continues. The results provide evidence that combining both modalities leads to more efficient navigation performance while using tactile feedback only reduces the users distraction.

Understanding shortcut gestures on mobile touch devices

Touch gestures become steadily more important with the ongoing success of touch screen devices. Compared to traditional user interfaces, gestures have the potential to lower cognitive load and the need for visual attention. However, nowadays gestures are defined by designers and developers and it is questionable if these meet all user requirements. In this paper, we present two exploratory studies that investigate how users would use unistroke touch gestures for shortcut access to a mobile phones key functionalities. We study the functions that users want to access, the preferred activators for gesture execution, and the shapes of the user-invented gestures. We found that most gestures trigger applications, letter-shaped gestures are preferred, and the gestures should be accessible from the lock screen, the wallpaper, and the notification bar. We conclude with a coherent, unambiguous set of gestures for the 20 most frequently accessed functions, which can inform the design of future gesture-controlled applications.

Geovisual interfaces to find suitable urban regions for citizens: a user-centered requirement study

Geographic retrieval and visualization systems are essential to satisfy users spatial information needs. However, the end users spatial information need is much more diverse and demanding in complex decision making scenarios such as: Persons moving to a new area need information about which place meets their individual demands. To analyze such requirements, we conducted a study with 18 users of different age group, knowledge, and expertise. In this paper we report the study methods, results, analysis and insights to build an end user-friendly geospatial decision support system.

Smarttention, please!: 2nd workshop on intelligent attention management on mobile devices

Today, many users of mobile devices are continuously confronted with a huge variety of information: notifications from Facebook, new application updates, won badges, or reminders. This leads to an information overload, which makes it hard to stay focused. This workshop will investigate approaches towards smart attention management systems. We will discuss the fundamental challenges of smart notifications and the design of proactive notification mechanisms. We invite submissions that focus on the understanding of users and their current, mobile information handling. We further appreciate contributions that propose design concepts for the interaction with smart attention management systems. The expected workshop outcome is a summary of emerging challenges in the design and development of smart attention management systems as well as approaches to address them.