In conditionally automated driving, assertive takeover requests (TORs) have been found to elicit faster responses in the transition from automated to manual control. However, despite this apparent benefit, concerns have been raised that assertive signals can stress the drivers, resulting in worse takeover quality and subsequent driving performance.

In mixed traffic environments, highly automated vehicles (HAV) can potentially be disruptive and a source of hazards due to their non-human driving behavior and a lack of “traditional” communication means (gestures, eye contact, and similar) to resolve issues or otherwise unclear situations. As a result, additional external human-machine interfaces (eHMI) for automated vehicles that replace the now absent human element in communication have been proposed. In this paper, we present the results from a study, in which two versions of a light band eHMI to communicate driving intend of an automated shuttle were evaluated in a real driving environment. We found that the green-red traffic light metaphor and simple animations could improve interaction success in certain aspects. We also found and discuss that the effect of using vs. not using the visual eHMIs was overall lower than expected and that the shuttle’s position and observable driving behavior seemed to play a larger role than anticipated.

First consumer-facing apps for medical self-diagnosis through Artificial Intelligence have hit the market only recently. These promise to detect malicious skin changes from photos or respiratory diseases from cough noises captured by the smartphone microphone, for example. While there is a large body of research on HCI-related aspects of mobile health applications, knowledge about the user perceptions of such novel AI-driven self-diagnosis apps and factors affecting their acceptance and adoption is scarce. In an online survey, we investigated the participants’ overall willingness-to-use (considering four types of captured and processed data) and identified trust factors and desirable features. We found that more than half of the participants would use AI-driven self-diagnosis apps, yet mainly integrated into prevailing general practitioner care. Based on the results, we draw conclusions which can guide the design, development, and launch of AI-driven self-diagnosis apps.

No longer only experts are confronted with (semi-)automated systems, yet automation has founds its way into our everyday lifes in various forms and applications. Based on a thorough literature review, we introduce a design space for “everyday automation” to uncover eight core dimensions of respective systems. These dimensions include the domain, the task type, the type of user interaction, and the automation level, among others. Visualized as a “morphological box”, this design space is particularly supposed to support the ideation of novel automated systems for everyday life.

Automation is finding its way into many parts of everyday life. This is manifested by the increasing opportunities for end users to offload decisions to their home appliances, to hand over control to their cars, to step into automated trains, or to go for shopping at self-checkout stores. Supported by artificial intelligence, emerging automated services are getting closer towards human cognitive functions, as they are integrating analysis and decision based on the processing of large information sets [ 48 ]. In anticipation of the broad impact that these emerging technologies will have on our sphere of life, a reflective and systematic consideration is necessary that leverages their full potential in terms of user experience. While there is a long human factors research tradition on automation, scholars have for long concentrated on highly specialized professional work tasks for trained personnel, such as control center operators or pilots. With technological innovations and new use cases in domains such as transport, home automation, and retail, the goal of designing automation for a broader population has become more important. This transition of automation technology towards the everyday life thus has put the experience of “naïve users” into the center of attention.

Due the involved counselling activities, the profession of social work might provide a promising, yet so far uninvestigated application field for voice assistants. To explore requirements and barriers for voice-based services in the field of social work, we conducted focus group sessions with 41 professionals. During the group discussions and through a questionnaire, we collected requirements for applying voice assistants in this professional setting and corresponding application ideas. Overall, the participants expected a positive impact of voice assistants on their profession. While the protection of the clients' sensitive data and the risk of their reduced social interactions need to be considered, the participants saw high potential in documentation services and the cooperative guidance of clients by human professionals and voice assistants. Future research should investigate the design of this interplay and study appropriate handover strategies between human experts and virtual assistants for specific social work services.

Once highly automated vehicles become available, drivers will be freed to perform activities other than driving when automated driving mode is activated. Such activities could include relaxing, reading, exercising, or working. The work of professional drivers such as truck drivers can be expected to be especially affected by this technology and to change accordingly as highly automated trucks enable the completion of other working related tasks during automated driving. But will such mobile working places be accepted by truck drivers? In this paper, we report on a survey (N=23) assessing technology acceptance towards Future Workplaces in highly Automated Trucks (FWAT). Results show that a majority of drivers is rather skeptical about FWAT, but that acceptance can be expected to strongly vary. Our paper provides some guidance on how to explain this variance and presents relevant acceptance factors for future FWAT usage.

In the domain of public transport, automation provides several advantages which can lead to better services for the customers. For tapping the full potential of future automated public transport services, passenger requirements have to be thoroughly considered in order to avoid shortcomings discouraging future users to remain or become customers and to support the role of public transit as sustainable backbone of transport.

The rise of autonomous and fully autonomous vehicles requires a closer examination of how people will interact with them. In this workshop, we especially address two areas: (1) What can we learn from mobile HCI for the interaction design between human drivers and the autonomous vehicle? (2) What opportunities for mobile HCI arise due to new freedoms for drivers, when they also take on the role of passengers in autonomous vehicles? The workshop will seek to further develop the challenges involved and/or to suggest early solutions through the use of a highly participative format.

Visual end-user programming interfaces are becoming increasingly important in the context of smart homes. This paper describes the comparative evaluation of two prototypes following different approaches: form-filling and data-flow programming. We assessed rule completion time, success, user experience and rule recollection as well as suitability to different user-groups. Participants were significantly faster and had a higher overall completion rate using form-filling, but remembered significantly more items when being presented with a data-flow visualization. We therefore recommend approaches that imbibe characteristics of both approaches for end-user programming in a smart home context with untrained users, focusing on a guided process flow, explicit logic and content-categorization.

End-user programming in smart homes addresses tasks that range from very simple to very complex. In this study we investigate how task complexity impacts performance when using two different visual programing representations: form-filling and data-flow programming. We invited 16 participants to create rules to solve smart-home situations of varying complexity and analyzed their completion rates for the two visual programming representations. We identify the following areas of difficulty for programming novices in our smart home scenario: choosing and connecting triggers and their specifications, and using Boolean operators. Both visual representations enabled users to specify complex rules, with advantages in different areas. They indicate that overall task complexity might be less decisive for performance than complexity of triggers and Boolean operators.

For various VR/MR/AR applications, such as virtual usability studies, it is very important that the participants have the feeling that they are really in the environment. This feeling of “being” in a mediated environment is described as presence. Two important factors that influence presence are the level of immersion and the navigation method. We developed two navigation methods to simulate natural walking using a Wii Balance Board and a Kinect Sensor. In this preliminary study we examined the effects of these navigation methods and the level of immersion on the participants' perceived presence in a 2×2 factorial between-subjects study with 32 participants in two different VEs (Powerwall and Mixed-Reality-See-Through-Glasses). The results indicate that reported presence is higher for the Kinect navigation and Powerwall for some facets of presence.

On-screen gamepads are increasingly used as controllers for video games on distant screens, yet lack the typical tactile feedback known from hardware controllers. We conducted a comparative lab study to investigate four smartphone gamepads inspired by traditional game controllers and mobile game controls (directional buttons, directional pad, floating joystick, tilt control). The study consisted of both completing a formal control test as well as controlling two popular video games of different genres ( Pac-Man and Super Mario Bros. ). The results indicate that the directional buttons require the most attention of the user, however, work precisely for direction-restricted navigational tasks. Directional pad and joystick showed a similar performance, yet they encourage drifting and unintended operations when the user is focused on the remote screen. While currently unfamiliar to many users, the floating joystick can reduce the glances at the device. Tilt turned out to be not sufficiently precise and quick for the investigated tasks. The article concludes with derived design guidelines with easily realizable measures for typical contexts such as casual gaming at home or spontaneous gaming on public displays.

Interactive opinion polls are a promising novel use case for public urban displays. However, voicing one's opinion at such a public installation poses special privacy requirements. In this paper, we introduce our ongoing work on investigating the roles of the interaction technique and the poll question in this novel context. We present a field study comparing three different voting techniques (public touch interface, personal smartphone by scanning a QR code, from remote through a short Web address) and three types of poll questions (general, personal, local). Overall, the results show that actively casting an opinion on a timely topic is highly appreciated by passers-by. The public voting opportunity through a touch screen is clearly preferred. Offering mobile or remote voting does not significantly increase the overall participation rate. The type of poll question has an impact on the number of participants but does not influence the preferred interaction modality.

Modern handheld devices can act as “magic lenses” for public displays and enable camera-based real-time interaction with their contents, thus allowing for manifold interactive applications in public space. To learn more about the characteristics of common techniques and to provide guidelines for new ones, a comparative user study was conducted. With regard to two basic task types (selection and translation) and two typical devices (smartphone and tablet), three interaction techniques in-depth were evaluated: direct touch-based input (Touch), cross-hair targeting (Target), and a new technique based on a dynamic cross-hair on the screen that snaps to visible nearby screen objects (Snap Target). The study results indicate that successful interaction with the Touch technique strongly depends on the usage context: Although Touch enables fast selection, it incurs many errors when small targets have to be selected on a smartphone. Target supports such difficult selections better, but Snap Target proved to be most robust in both investigated task types. Also, users stated that they felt best supported by the latter technique. Cross-hair-based techniques, especially Snap Target, were found to be well suitable for scenarios where several device types need to be supported under similar conditions. Implications and further work are discussed.

This paper presents a semantic policy adaptation technique and its applications in the context of smart building setups. We study how semantic rules which are created for one set of contextual conditions are affected when one of the context parameters changes. In particular, rules for triggering alerts and monitoring appliances and their adaptation with changing contexts have been studied in detail. We then describe how this changing context triggers changes in other related context parameters. This technique has been implemented to demonstrate its feasibility, evaluated and positively accepted during trials with users of a real-life semantically empowered smart building setup.

The design of traffic management systems is challenging because of the large amount of dynamic data which has to be analysed by operators. Systems have to be designed appropriately to enable operators to react efficiently and quickly. The following paper gives an overview of guidelines derived from empirical research in cognitive psychology and HCI. These guidelines specifically address the design of traffic management systems. The following topics seem to be especially relevant: visual perception, geographic data, perception of motion, monitoring of tasks and interaction. These guidelines can help to design usable and useful systems.

Traffic information from diverse transportation domains is increasingly becoming interlinked and accessible in real-time. Upcoming intermodal transportation services could advise drivers to change to a public transportation means, especially in case of severe congestions on the road. We present a road user study with 52 participants with an in-car intermodal routing prototype that gained first empirical evidence on the user requirements in such scenarios. We found that a considerable number of recommendations for modal shifts to public transit were actually accepted by the drivers. In-car inquiry results highlight that decision-making under such complex time-constrained conditions needs to be supported by a considerable amount of updated, detailed and valid information about time savings, pricing, connections and also the actual route situation ahead. We show that the presentation of such large amounts of information should be feasible without categorical safety losses, even with small-screen devices (such as smartphones). To guide further development, related design experiences with regard to presentation modality, system input, and screen design are shared.

As everyday companions, smartphones are well-suited tools for controlling interactive applications on large public displays. To allow concurrent interaction by multiple users beyond traditional collaborative scenarios we introduce the idea of virtually augmented public screens for creating personalized views and thus literally enabling "private public screens". We present a fully functional research prototype in form of a Video Wall application and report on first experiences gathered from a comparative user study. The results show that the proposed personalized Augmented Reality approach, which allows each user to have a private view on the public display, is preferred over a purely competitive mode, where the public display is shared between the users. Further, our study shows that social activity indicators informing about the activities of other users are well appreciated.

Today's in-car information systems are undergoing an evolution towards realistic visualization as well as to real-time telematics services. In a road study with 31 participants we explored the communication of safety information to the driver. We compared three presentation styles: audio-only, audiovisual with a conventional map, and audiovisual with augmented reality. The participants drove on a motorway route and were confronted with recommendations for route following, speed limitation, lane utilization, unexpected route change, and emergency stops. We found significant differences between these safety scenarios in terms of driving performance, eye glances and subjective preference. Comparing the presentation styles, we found that following such recommendations was highly efficient in the audio-only mode. Additional visual information did not significantly increase driving performance. As our subjective preference data also shows, augmented reality does not necessarily create an added value when following safety-related traffic recommendations. However, additional visual information did not interfere with safe driving. Importantly, we did not find evidence for a higher distraction potential by augmented reality; drivers even looked slightly less frequently on the human-machine interface screen in the augmented reality mode than with conventional maps.

The vision-based detection of hand gestures is one technological enabler for Natural User Interfaces which try to provide a natural and intuitive interaction with computers. In particular, mobile devices might benefit from such a less device-centric but more natural input possibility. In this paper, we introduce our ongoing work on the visual markerless detection of fingertips on mobile devices. Further, we shed light on the potential of mobile hand gesture detection and present several promising use cases and respective demo applications based on the presented engine.

Using mobile devices for exploring and interacting with the user's physical environment is among the most promising candidates for commercially successful future telecommunication services and applications. This trend is confirmed by the rollout of latest mobile phones equipped with advanced navigation features like built-in GPS receivers, digital compasses and acceleration sensors. The increasing technological potential of Mobile Spatial Interaction (MSI), however, requires a wider comprehension of appropriate visualization possibilities for spatially referenced content in the field of Mobile Human-Computer Interaction.In this paper, we argue for an integrated approach comprising innovations in MSI with latest advances in visualization. In order to demonstrate the potential of this joint approach, we present a series of three related projects and highlight in each case research challenges and results in the field of Mobile HCI and mobile appli-cation development as well as corresponding advances of the underlying server-side rendering algorithms.

This paper explores the design space of Smart Horizons -- mobile applications offering to look at virtual representations of the user's visible surroundings. We conducted an outdoor field study with a fully implemented spatially aware restaurant finder service, in which participants accessed points of interest (POI) virtually attached to nearby buildings. The overall finding was that all orientation-aware visualizations of the nearby environment were highly preferable to a conventional orientation-agnostic presentation. Based on the participants' comparative judgments after using the system prototype, first design recommendations along the dimensions of perspective, field of view and realism are provided. Further research directions are proposed.

In this paper we present an application framework that leverages geospatial content on the World Wide Web by enabling innovative modes of interaction and novel types of user interfaces on advanced mobile phones and PDAs. We discuss the current development steps involved in building mobile geospatial Web applications and derive three technological pre-requisites for our framework: spatial query operations based on visibility and field of view, a 2.5D environment model, and a presentationindependent data exchange format for geospatial query results. We propose the Local Visibility Model as a suitable XML-based candidate and present a prototype implementation.

Spatial information appliances (SIA), which enable mobile users to interact with the physical environment, have recently received an increasing amount of interest from the research community. This paper presents a comparative outdoor user study on conceptual designs for 4 interaction areas considered important for SIAs: selection, search, information sniffing, and remote viewing. Implications for future research are discussed.

In this paper, we report on a comparative user study about the quality of mobile speech synthesis methods. We measured the impact of device class, data rate, synthesis method (diphone vs. non-uniform unit-selection) and lexicon usage on speech quality (word comprehension and several subjective satisfaction metrics). Seven practically relevant speech synthesis implementations and one natural voice were evaluated, applying the method recommended in ITU-T P.85, with additional pairwise comparisons. As a general result, although the overall subjective ratings of the synthetic voices differed significantly, the word comprehension rates were quite similar. We found a significant impact of data rate and synthesis method on the mean subjective speech quality, but not on word comprehension. The use of a lexicon in embedded speech synthesis slightly improved the perceived pronunciation quality.