Design of a Virtual School Environment for
Power Wheelchair Training
Max Edmands1, Alana Searleman2 and Katelynn Wilton3
Advised by Prof. Janice T. Searleman4
Individuals with physical and/or cognitive disorders who use a standard wheelchair (W/C) for mobility
are frequently dependent on an assistant to maneuver the wheelchair for them. In many of these cases the
person is capable of controlling a joystick, which is the means for driving a power W/C. However,
insurance companies require a candidate to document that he or she is properly trained to operate a power
W/C before funding the purchase. It can be very difficult for people, particularly in rural or remote areas,
to obtain a power W/C specific to their needs to practice with. In addition, training is time consuming
and potentially unsafe. Training requires the presence of an Occupational Therapist (OT) to guide the
W/C user, making sure that he or she can complete basic tasks without injury. Virtual Reality can
remediate this problem by providing a safe environment in which to learn how to operate a power W/C,
using the same technology that is used to train pilots to operate a jet aircraft. Towards this goal, a
Virtual Reality Wheelchair (VRWC) training simulator was developed at Clarkson [1].
The VRWC training simulator consists of a hydraulic platform, head-mounted display (HMD), headtracker, power W/C joystick, 3D visualization software, and a computer to control the simulation. Users
would mount the platform on their manual W/C via a ramp, be buckled in with a safety belt, put on the
HMD and head-tracker, and strap the power W/C joystick to the arm of their own W/C. Then they would
be able to maneuver a “virtual” W/C through a 3D environment with the joystick, and get the sensation of
moving as the platform responds to the simulation. 3D interactive environments were created with the
Virtools authoring system [2]. In addition to the fully immersive system, the same software can be used
with a web browser such as Internet Explorer or Firefox to deliver the virtual environment to the student,
with or without the HMD, and with an ordinary joystick. This allows a student to practice at school or at
home since the training is readily available on a wide variety of platforms, which is a distinct advantage
for the training process [3].
Previously, two environments were developed for the VRWC simulator. In one, a two-story house was
created, complete with a W/C ramp to the front porch, and an elevator to get to the second floor [4, 5]. A
trainee would see the house through the HMD, and would feel the sensation of going up the ramp as the
moving platform tilted, or turning a corner as the platform rotated. The head-tracker would sense
movements of their head, so they could look around in the house. In the second environment, a training
facility was developed as a series of rooms where the trainee could practice a specific skill in each room
[6]. These skills included moving down a narrow corridor without bumping into walls, driving through a
maze, moving around obstacles, and so on. In each practice session, measurements were taken, such as
the number of times the trainee collided with an obstacle, how many times the joystick was extraneously
moved, or how long it took to complete each task. In this way, progress for an individual could be
monitored.
1
Class of 2009, Computer Science, Honors Program
Class of 2008, Digital Arts and Sciences
3 Class of 2011, Computer Science, Honors Program
4 Dept. of Computer Science, Faculty Member
2
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Recently, a model of a typical school [7] was created in Autodesk 3D Studio Max (3ds) [8]. This
provided a setting appropriate for our intended audience: children with Cerebral Palsy who are
recommended by their OTs as suitable candidates for power W/C training. This model complied with the
Americans with Disabilities Act Accessibility Guidelines [9]. We further developed this virtual school
environment so the subject can learn how to control a power W/C while navigating his or her way through
the school. To facilitate learning and to motivate the student, a series of tasks will be assigned in the form
of a game. To accomplish this goal, the 3ds model of the school was imported into Virtools, and scripts
were created to simulate typical school activities. We also used Autodesk Maya [10] and Adobe
Photoshop [11] to enhance the realism of the environment.
One of the problems with the house environment and the training facility was the lack of a proper physics
model. A real W/C often has wheels mounted on casters, so to back a W/C out of a tight spot it is not
enough to simply move the joystick backwards. If the wheels are at an angle, moving the joystick straight
back will cause the W/C to move in an arc. To increase the realism of our environment, we used
Virtools’ ability to physicalize objects with Havok's popular physics engine [12]. With the physics engine
enabled, players will collide with walls rather than passing through them, gravity will cause objects to fall
to the floor, and the wheels on casters will operate correctly [13].
An interactive training program such as this one is referred to as a serious game. An effective serious
game should engage its user in the same way that a common video game would [14]. For our program,
therefore, it was essential to develop storyboards to create a coherent plot for our training scenario. With a
schedule to aid him or her, the player must travel from class to class, accomplishing objectives in each
classroom. In the gym, for example, the player must navigate an obstacle course. In the library, the player
must take a book off the shelf and bring it to a table. The player also needs to navigate the hallways
between classes without colliding with classmates or being late for class. The player will be given a
choice between three levels of difficulty: easy, medium, and hard. OTs will also have the option to create
a fourth, customizable, level of difficulty. This adaptability has proven instrumental in other programs
similar to ours, such as military training programs [3]. As in the previous work, metrics can be saved with
each session of the game to monitor progress.
Many of the tasks that the player must complete require the use of computer-controlled intelligent agents.
Taking the form of classmates, teachers, assistants, and other people that one might find at a school, these
intelligent agents will interact with the player, by either getting out of the player's way or giving the
player tips and pointers. Future development of the virtual school will implement these agents.
Eventually, this project should lead to a program that can help to train individuals in the use of a power
W/C, and also help OTs correctly gauge the progress of a patient in their care. In addition, the school is
not only limited to power W/C training. The house environment, for example, was adapted to help
rehabilitate stroke patients as they performed everyday tasks in the kitchen [15]. With a few simple
modifications, the school can be used as a test bed for other training simulations, such as teaching life
skills to students with cognitive impairments.
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