Environmental Engineering Reference
In-Depth Information
Information about a scenario of interest to the patients was gathered. The VR system was
used to present this scenario in the form of an environment where the patients performed a
VR-based exercise in order to induce the therapy needed to correct their gait problems. The
VR system was employed to present the patients with VR tasks (in the form of a painting
exercise) closely linked with the therapy needed to correct or improve any abnormality in
their walking patterns. This stage model phase modeled all the primitives, visual and audio,
of both the task-specific exercise and the VR environment as formalized in the scenario
stage. The virtual reality task was based on a painting exercise, which served the purpose of
inducing the therapeutic movements needed for the functional recovery or improvements of
the lower extremities of the patients. The VR-based painting exercise was employed for the
purpose of simulating visually immersive therapy exercise on a PC without having to
physically use real paints, brushes, boards or papers.
Research has recently been focused on the painting process and virtual reality technology
(Lin, Baxter, Scheib & Wendt, 2004), and the clinical community for the work agreed that the
painting task is capable of inducing the movement patterns that are closely linked with the
therapy needed to correct ambulatory problems, especially in ankle and foot movements.
The painting exercise induced in the leg the complex strokes associated with physical
painting in the real world. A graphical user interface provided the therapist with a simple
and minimal set of keystrokes with which the VR exercises were manipulated for the
appropriate level of exercise difficulty for each patient. The VR-based painting exercise
presented the patients with windows of different sizes to be covered. The patients were
required to cover the windows with 'red blinds' using their hemiplegic legs. The window's
color, initially cyan over a blue background, becomes red over a blue background when
completely covered. The therapist viewed the painting process on a computer screen as the
patient performed the exercise within a virtual environment using the head mounted
display. The author designed a 'LegMouse' and a 'LegPad' (Akinladejo, 2005), which the
patient used to accomplish the painting exercise. The LegPad was attached to the patient's
hemiplegic leg for movements on the LegMouse. The LegPad was designed, in consultation
with the clinical community, with a hemispheric base in order to allow dorsiflexion, plantar
flexion, inversion and eversion movements of the ankle joints. As the patient moved his or
her leg with the LegPad over the LegMouse, the painting program caused the cursor on the
computer screen to 'paint' a defined window. There were four different window areas, each
corresponding to the task difficulty level that the patient was performing. The painting
process stopped whenever the cursor moved outside a window area. Thus the patient was
constantly challenged with the task of keeping the cursor within the window area in the
virtual environment, and also with the task of moving his or her hemiplegic leg in all
directions for the painting process to continue. These movements (e.g., dorsiflexion and
plantar flexion movements) helped to induce in the leg the therapy needed to correct or
improve ambulatory problems in the ankle joint thereby leading to better walking skills.
Some images that present the patient's view of the systems is presented. The painting
exercise was modeled using OpenGL, an environment for developing portable, interactive
2D and 3D graphics applications. This application programming interface (API) is widely
used on a number of computer platforms for innovative developments through its broad set
of rendering, texture mapping, special effects, and other powerful visualization functions
available for application developers (http://www.opengl.org/about/overview.html).
OpenGL is a truly open, vendor-neutral, multiplatform graphics standard that provides
consistent visual display results on any OpenGL API-compliant hardware irrespective of the
