Real Time Animation of Virtual Humans: A Trade-off Between Naturalness and Control

Virtual humans are employed in many interactive applications using 3D virtual environments, including (serious) games. The motion of such virtual humans should look realistic (or ‘natural’) and allow interaction with the surroundings and other (virtual) humans. Current animation techniques differ in the trade-off they offer between motion naturalness and the control that can be exerted over the motion. We show mechanisms to parametrize, combine (on different body parts) and concatenate motions generated by different animation techniques. We discuss several aspects of motion naturalness and show how it can be evaluated. We conclude by showing the promise of combinations of different animation paradigms to enhance both naturalness and control

An Animation Framework for Continuous Interaction with Reactive Virtual Humans

We present a complete framework for animation of Reactive Virtual Humans that offers a mixed animation paradigm: control of different body parts switches between keyframe animation, procedural animation and physical simulation, depending on the requirements of the moment. This framework implements novel techniques to support real-time continuous interaction. It is demonstrated on our interactive Virtual Conductor

Mid-Air Haptics for Control Interfaces

Control interfaces and interactions based on touch-less gesture tracking devices have become a prevalent research topic in both industry and academia. Touch-less devices offer a unique interaction immediateness that makes them ideal for applications where direct contact with a physical controller is not desirable. On the other hand, these controllers inherently lack active or passive haptic feedback to inform users about the results of their interaction. Mid-air haptic interfaces, such as those using focused ultrasound waves, can close the feedback loop and provide new tools for the design of touch-less, un-instrumented control interactions. The goal of this workshop is to bring together the growing mid-air haptic research community to identify and discuss future challenges in control interfaces and their application in AR/VR, automotive, music, robotics and teleoperation

Touching the invisible: Localizing ultrasonic haptic cues

While mid-air gestures offer new possibilities to interact with or around devices, some situations, such as interacting with applications, playing games or navigating, may require visual attention to be focused on a main task. Ultrasonic haptic feedback can provide 3D spatial haptic cues that do not demand visual attention for these contexts. In this paper, we present an initial study of active exploration of ultrasonic haptic virtual points that investigates the spatial localization with and without the use of the visual modality. Our results show that, when providing haptic feedback giving the location of a widget, users perform 50% more accurately compared to providing visual feedback alone. When provided with a haptic location of a widget alone, users are more than 30% more accurate than when given a visual location. When aware of the location of the haptic feedback, active exploration decreased the minimum recommended widget size from 2cm2 to 1cm2 when compared to passive exploration from previous studies. Our results will allow designers to create better mid-air interactions using this new form of haptic feedback

Is movement better? Comparing sedentary and motion-based game controls for older adults

Providing cognitive and physical stimulation for older adults is critical for their well-being. Video games offer the opportunity of engaging seniors, and research has shown a variety of positive effects of motion-based video games for older adults. However, little is known about the suitability of motion-based game controls for older adults and how their use is affected by age-related changes. In this paper, we present a study evaluating sedentary and motion-based game controls with a focus on differences between younger and older adults. Our results show that older adults can apply motion-based game controls efficiently, and that they enjoy motion-based interaction. We present design implications based on our study, and demonstrate how our findings can be applied both to motion-based game design and to general interaction design for older adults. Copyright held by authors

Visual Pseudo Haptics for a Dynamic Squeeze / Grab Gesture in Immersive Virtual Reality

In this work, we analyze the suitability of employing visual feedback for pseudo haptics as a replacement for active haptics in an immersive virtual reality (VR) environment. A controller-free gesture interaction is widely considered to be a natural user interface in VR. As the controller is not employed, the lack of active haptic feedback can often result in a frustrating experience for complex dynamic gestures, e.g., grab, squeeze, clasp, etc. These actions are very easy to perform using specialized devices or controllers with active haptic feedback, e.g., data gloves with force feedback or controllers with analog triggers and vibrations can be utilized for immediate or continuous feedback. In contrast, these mechanisms are completely missing in a controller-free interaction. We present an on-screen visual mechanism as the pseudo haptic feedback of a dynamic squeeze/grab gesture to replace the active haptic feedback. Our proposed approach allows for the continuous visualization of a squeeze/grab gesture. We implemented an interaction mechanism to test the visualization for these dynamic gestures and compared it with a system with no pseudo haptics. The results from the user study show that an on-screen continuous visualization can be used as pseudo haptics for a dynamic squeeze/grab gesture in an immersive VR environment

Affective interactions between expressive characters

When people meet in virtual worlds they are represented by computer animated characters that lack a variety of expression and can seem stiff and robotic. By comparison human bodies are highly expressive; a casual observation of a group of people mil reveals a large diversity of behavior, different postures, gestures and complex patterns of eye gaze. In order to make computer mediated communication between people more like real face-to-face communication, it is necessary to add an affective dimension. This paper presents Demeanour, an affective semi-autonomous system for the generation of realistic body language in avatars. Users control their avatars that in turn interact autonomously with other avatars to produce expressive behaviour. This allows people to have affectively rich interactions via their avatars

A human computer interactions framework for biometric user identification

Computer assisted functionalities and services have saturated our world becoming such an integral part of our daily activities that we hardly notice them. In this study we are focusing on enhancements in Human-Computer Interaction (HCI) that can be achieved by natural user recognition embedded in the employed interaction models. Natural identification among humans is mostly based on biometric characteristics representing what-we-are (face, body outlook, voice, etc.) and how-we-behave (gait, gestures, posture, etc.) Following this observation, we investigate different approaches and methods for adapting existing biometric identification methods and technologies to the needs of evolving natural human computer interfaces