Ming Ki Chong

HandsDown: hand-contour-based user identification for interactive surfaces

HandsDown is a novel technique for user identification on interactive surfaces. It enables users to access personal data on a shared surface, to associate objects with their identity, and to fluidly customize appearance, content, or functionality of the user interface. To identify, users put down their hand flat on the surface. HandsDown is based on hand contour analysis; neither user instrumentation nor external devices are required for identification. Characteristic features of the hand are initially extracted from images captured by the surfaces camera system and then classified using Support Vector Machines (SVM). We present a proof-of-concept implementation and show results of our evaluation which indicates the techniques robustness for user identification within small groups. Additionally, we introduce a set of interaction techniques to illustrate how HandsDown can improve the user experience, and we discuss the design space of such interactions.

GesturePIN: using discrete gestures for associating mobile devices

Mobile devices with wireless network capabilities can be associated to form ad hoc networks to share resources; however, such an association of devices requires authentication. At present, PIN is the common authentication method, but in many cases, small devices may not have input interfaces to accommodate PIN entry. We therefore design a gesture-based authentication scheme, called GesturePIN, for associating multiple mobile devices; our solution provides the advantage of being adaptable to any PIN authentication systems. We have also conducted a quantitative user study to understand the speed and accuracy of people using our gesture-based system compared to using PIN.

A Survey of User Interaction for Spontaneous Device Association

In a wireless world, users can establish ad hoc virtual connections between devices that are unhampered by cables. This process is known as spontaneous device association. A wide range of interactive protocols and techniques have been demonstrated in both research and practice, predominantly with a focus on security aspects. In this article, we survey spontaneous device association with respect to the user interaction it involves. We use a novel taxonomy to structure the survey with respect to the different conceptual models and types of user action employed for device association. Within this framework, we provide an in-depth survey of existing techniques discussing their individual characteristics, benefits, and issues.

IdLenses: dynamic personal areas on shared surfaces

IdLenses is a novel interaction concept to realize user-aware interfaces on shared surfaces. Users summon virtual lenses which allow for personalized input and output. The ability to create a lens instantaneously anywhere on the surface, and to move it around freely, enables users to fluidly control which part of their input is identifiable, and which shall remain anonymous. In this paper, we introduce the IdLenses concept and its interaction characteristics. Further, we discuss how it enables the personalization of input and output on shared surfaces.

GazeHorizon: enabling passers-by to interact with public displays by gaze

Public displays can be made interactive by adding gaze control. However, gaze interfaces do not offer any physical affordance, and require users to move into a tracking range. We present GazeHorizon, a system that provides interactive assistance to enable passers-by to walk up to a display and to navigate content using their eyes only. The system was developed through field studies culminating in a four-day deployment in a public environment. Our results show that novice users can be facilitated to successfully use gaze control by making them aware of the interface at first glance and guiding them interactively into the tracking range.

Usability classification for spontaneous device association

As wireless devices increasingly becoming ubiquitous, spontaneous interaction opportunities are accordingly becoming common. Although spontaneous interaction research has been ongoing for many years, a key question of spontaneous interaction still remains open: how can users associate devices in a natural, intuitive and secure manner. Over the past decade, researchers have demonstrated a plethora of device association techniques. Nonetheless, users were often neglected during design or they were only involved in a later stage, like testing. We argue that since device association is performed by end-users, usability factors need to be considered in the early stage of design. In this article, we present a categorisation of factors that influence the usability of device association. This paper aims at providing a framework that informs researchers and system designers of the considerations needed when designing or adopting an association technique.

Eye tracking for public displays in the wild

AbstractIn public display contexts, interactions are spontaneous and have to work without preparation. We propose gaze as a modality for such contexts, as gaze is always at the ready, and a natural indicator of the user’s interest. We present GazeHorizon, a system that demonstrates spontaneous gaze interaction, enabling users to walk up to a display and navigate content using their eyes only. GazeHorizon is extemporaneous and optimised for instantaneous usability by any user without prior configuration, calibration or training. The system provides interactive assistance to bootstrap gaze interaction with unaware users, employs a single off-the-shelf web camera and computer vision for person-independent tracking of the horizontal gaze direction and maps this input to rate-controlled navigation of horizontally arranged content. We have evaluated GazeHorizon through a series of field studies, culminating in a 4-day deployment in a public environment during which over a hundred passers-by interacted with it, unprompted and unassisted. We realised that since eye movements are subtle, users cannot learn gaze interaction from only observing others and as a result guidance is required.

Gaze-Shifting: Direct-Indirect Input with Pen and Touch Modulated by Gaze

Modalities such as pen and touch are associated with direct input but can also be used for indirect input. We propose to combine the two modes for direct-indirect input modulated by gaze. We introduce gaze-shifting as a novel mechanism for switching the input mode based on the alignment of manual input and the users visual attention. Input in the users area of attention results in direct manipulation whereas input offset from the users gaze is redirected to the visual target. The technique is generic and can be used in the same manner with different input modalities. We show how gaze-shifting enables novel direct-indirect techniques with pen, touch, and combinations of pen and touch input.

How groups of users associate wireless devices

Group association, the process of connecting a group of devices, opens up new opportunities for users to spontaneously share resources. Research has shown numerous techniques and protocols for group association; however, what people intuitively do to associate a group of devices remains an open question. We contribute a study of eliciting device association techniques from groups of non-technical people. In all, we collected and analysed 496 techniques from 61 participants. Our results show that mobility and physicality of devices influence how people perceive groups association. We present a complete set of user-defined techniques with subjective ratings and popularity scores. We examined peoples rationale and the effects of different device form factors. We analysed the techniques based on the roles that users assume with respect to device association. Our findings draw out insights from the perspective of users for design of group association.

Look together: using gaze for assisting co-located collaborative search

Gaze information provides indication of users focus which complements remote collaboration tasks, as distant users can see their partner’s focus. In this paper, we apply gaze for co-located collaboration, where users’ gaze locations are presented on the same display, to help collaboration between partners. We integrated various types of gaze indicators on the user interface of a collaborative search system, and we conducted two user studies to understand how gaze enhances coordination and communication between co-located users. Our results show that gaze indeed enhances co-located collaboration, but with a trade-off between visibility of gaze indicators and user distraction. Users acknowledged that seeing gaze indicators eases communication, because it let them be aware of their partner’s interests and attention. However, users can be reluctant to share their gaze information due to trust and privacy, as gaze potentially divulges their interests.