72 research outputs found
In-Home Delivery of Constraint-Induced Movement Therapy via Virtual Reality Gaming
Purpose: People with chronic hemiparesis are frequently dissatisfied with the recovery of their hand and arm, yet many lack access to effective treatments. Constraint-induced movement therapy (CI therapy) effectively increases arm function and spontaneous use in persons with chronic hemiparesis. The purpose of this study was to determine the feasibility and measure safety and outcomes of an in-home model of delivering CI therapy using a custom, avatar-based virtual reality game.
Methods: Seventeen individuals with chronic hemiparesis participated in this pretest/posttest quasi-experimental design study. The 10-day intervention had three components: 1) high-repetition motor practice using virtual reality gaming; 2) constraint of the stronger arm via a padded restraint mitt; and 3) a transfer package to reinforce arm use. Feasibility of the intervention was evaluated through comparison to traditional CI therapy and through participants’ subjective responses. The primary outcome measures were the Wolf Motor Function Test (WMFT) and the Motor Activity Log quality of movement scale (MAL-QOM).
Results: On average, participants completed 17.2 ± 8 hours and 19,436 repetitions of motor practice. No adverse events were reported. Of 7 feasibility criteria, 4 were met. WMFT rate and MAL-QOM increased, with effect size (Cohen’s d) of 1.5 and 1.1, respectively.
Conclusions: This model of delivering CI therapy using a custom, avatar-based virtual reality game was feasible, well received, and showed preliminary evidence of being a safe intervention to use in the home for persons with chronic hemiparesis
Distance Field Illumination: A Rendering Method to Aid in Navigation of Virtual Environments
Vol.8,No.3:1—21 Efficient Splatting Using Modern Graphics Hardware
Abstract. Interactive volume rendering for data set sizes larger than one million samples requires either dedicated hardware, such as three-dimensional texture mapping, or a sparse representation and rendering algorithm. Consumer graphics cards have seen a rapid explosion of performance and capabilities over the past few years. This paper presents a splatting algorithm for direct volume rendering that utilizes the new capabilities of vertex programs and the OpenGL imaging extensions. This paper presents three techniques: immediate mode rendering, vertex shader rendering, and point convolution rendering, to implement splatting on a PC equipped with an NVIDIA GeForce4 display card. Per-splat and per-voxel render time analysis is conducted for these techniques. The results show that vertex-shader rendering offers an order of magnitude speed-up over immediate mode rendering and that interactive volume rendering is becoming feasible on these consumer-level graphics cards for complex volumes with millions of voxels. 1
Fast Dynamic Flow Volume Rendering Using Textured Splats on Modern Graphics Hardware
Dynamic flow volume rendering of three-dimensional vector fields offers better insights into the continuum and dynamics of the data field under investigation. Consumer graphics cards have seen a rapid explosion of performance and capabilities over the past few years. This paper explores the development of the Textured Splats algorithm for direct flow volume rendering of vector fields, that utilizes this new hardware. This paper presents the technique using new hardware that supports vertex programs, OpenGL multi-textures and register combiner extensions to implement fast dynamic flow volume rendering on a PC. Several anisotropic textured splats are investigated to implement flow volume rendering
Real-time slicing of data space
Abstract This can be a costly operation. When the data is arranged Real-time rendering of iso-contour surfaces is problematic for large complex data sets. In this paper, an algorithm is presented that allows very rapid representation of an interval set surrounding a iso-contour surface. The algorithm draws upon three main ideas. A fast indexing scheme is used to select only those data points near the contour surface. Hardware assisted splatting is then employed on these data points to produce a volume rendering of the interval set. Finally, by shifting a small window through the indexing scheme or data space, animated volumes are produced showing the changing contour values. In addition to allowing fast selection and rendering of the data, the indexing scheme allows a much compressed representation of the data by eliminating "noise" data points
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