Tuukka M. Takala

Survey of 3DUI applications and development challenges

We present a survey of the current generation of 3D user interface (3DUI) applications, their developers, and development issues. 3DUI developing experiences from 71 developers - as well as information about 56 unique 3DUI applications - were collected and analysed. The statistics presented in this paper give a broad view over the 3DUI field and indicate current trends in 3DUI applications, such as the most commonly used hardware and software. Popularity of Kinect and Move controllers are compared as we discuss how entertainment industry can embrace hobbyist innovation. Our results show that reuse of high-level interaction features is rare, even though 3DUI toolkits are widely used; most developers painstakingly implement common features like navigation and object manipulation for each 3DUI application, as opposed to inheriting them from a toolkit. We also introduce criteria for measuring 3DUI development difficulty and two ways of benchmarking 3DUI toolkits, and present example benchmarks using data from our survey.

Body-controlled trampoline training games based on computer vision

This work in progress -paper describes our efforts in developing trampoline training games using computer vision technology. The study is part of a project about developing digitally augmented exercise environments for faster, safer and more engaging sports training. We describe four initial prototypes and the feedback obtained from testing them both with circus students and with people with no background in trampolining.

Reality-based User Interface System (RUIS)

We introduce Reality-based User Interface System (RUIS), a platform that even novice programmers can easily use for prototyping novel user interfaces. We implemented a puzzle application with a 3D user interface employing modified Nintendo Wii Remotes as 6-DOF controllers to showcase some of the features that are possible with our platform: two-handed gestural interaction, natural interaction metaphors, and haptic feedback. We conducted a basic user study with 16 participants to evaluate the puzzle application and its 3D user interface. The results show how test subjects using the puzzle application tended to rate the 3D user interface to be more fun, intuitive, and realistic than a traditional mouse interface.

Full body interaction in virtual reality with affordable hardware

Summary form only given. Recently a number of affordable game controllers have been adopted by virtual reality (VR) researchers [1][4]. We present a video1 of a VR demo called TurboTuscany, where we employ such controllers; our demo combines a Kinect controlled full body avatar with Oculus Rift head-mounted-display [2]. We implemented three positional head tracking schemes that use Kinect, Razer Hydra, and PlayStation (PS) Move controllers. In the demo the Kinect tracked avatar can be used to climb ladders, play with soccer balls, and otherwise move or interact with physically simulated objects. PS Move or Razer Hydra controller is used to control locomotion, and for selecting and manipulating objects. Our subjective experience is that the best head tracking immersion is achieved by using Kinect together with PS Move, as the latter is more accurate and responsive while having a large tracking volume. We also noticed that Oculus Rifts orientation tracking has less latency than any of the positional trackers that we used, while Razer Hydra has less latency than PS Move, and Kinect has the largest latency. Besides positional tracking, our demo uses these three trackers to correct the yaw drift of Oculus Rift. TurboTuscany was developed by using our RUIS toolkit, which is a software platform for VR application development [3]. The demo and RUIS toolkit can be downloaded online2.

RUIS: a toolkit for developing virtual reality applications with spatial interaction

We introduce Reality-based User Interface System (RUIS), a virtual reality (VR) toolkit aimed for students and hobbyists, which we have used in an annually organized VR course for the past four years. RUIS toolkit provides 3D user interface building blocks for creating immersive VR applications with spatial interaction and stereo 3D graphics, while supporting affordable VR peripherals like Kinect, PlayStation Move, Razer Hydra, and Oculus Rift. We describe a novel spatial interaction scheme that combines freeform, full-body interaction with traditional video game locomotion, which can be easily implemented with RUIS. We also discuss the specific challenges associated with developing VR applications, and how they relate to the design principles behind RUIS. Finally, we validate our toolkit by comparing development difficulties experienced by users of different software toolkits, and by presenting several VR applications created with RUIS, demonstrating a variety of spatial user interfaces that it can produce.

Enhancing spatial perception and user experience in video games with volumetric shadows

In this paper, we investigate the use of volumetric shadows for enhancing three-dimensional perception and action in third-person motion games. They offer an alternative to previously studied cues and visual guides. Our preliminary survey revealed that from the games that require Kinect, 37% rely primarily on a third-person view and 9% on a first-person view. We conducted a user study where 30 participants performed object reaching, interception, and aiming tasks in six different graphical modes of a video game that was controlled using a Kinect sensor and PlayStation Move controllers. The study results indicate that different volumetric shadow cues can affect both the user experience and the gameplay performance positively or negatively, depending on the lighting setup. Qualitative user experience analysis shows that playing was found to be most easy and fluent in a typical virtual reality setting with stereo rendering and flat surface shadows.

Virtual ball catching performance in different camera views

Virtual camera design is an important but tricky part of creating virtual reality experiences; interaction can feel awkward if the camera is not placed exactly at the users eyes, but on the other hand a 3rd person perspective (3PP) can provide a better view of the environment and/or the avatar. To inform camera design, we contribute the first study that systematically explores and quantifies how interaction difficulty changes when the camera is moved between a natural 1st person perspective (1PP) and a typical 3PP where the camera is behind and above the user. In our experiment, 24 participants catched flying virtual balls in seven different camera views. Catching performance degraded almost linearly as a function of camera distance from 1PP, and adaptation to non-1PP was slow or non-existent after a quick initial and partial adaptation. Our result suggest that natural 1PP should be used whenever possible, and transitions between views should be minimized to minimize the user constantly struggling to adapt. We also discuss how our results can be explained by the relation of camera perspective and retinal optical flow, and what interaction techniques can mitigate 3PP interaction problems.