Information Technology Reference
In-Depth Information
serious disadvantages compared to other children. Adults who lose their independent
means of locomotion become less self-sufficient, raising a negative attitude towards
themselves. The loss of mobility originates obstacles that reduce the personal and
vocational objectives [1]. Therefore it is necessary to develop technologies that can
aid this population group, in a way to assure the comfort and independence of the
elderly and handicapped people. Wheelchairs are important locomotion devices for
those individuals. There is a growing demand for safer and more comfortable wheel-
chairs, and therefore, a new Intelligent Wheelchair (IW) concept was introduced.
However, most of the Intelligent Wheelchairs developed by distinct research laborato-
ries [1] have hardware and software architectures very specific for the used wheel-
chair model/developed project and are typically very difficult to configure in order for
the user to start using them.
The paper is organized as follows: Section 2 presents the state of art on intelligent
wheelchairs and the IntellWheels project. Section 3 contains a description of the me-
thodology for automatically extracting the users' profiles in order to give the best
interface. The implementation of the system is presented in section 4 and the experi-
ments and results achieved are presented in section 5. Finally some conclusions and
future work are described in the last section.
2
Intelligent Wheelchairs
In the last years several prototypes of Intelligent Wheelchairs have been developed
and many scientific work has been published [2] [3] in this area. Simpson [1] provides
a comprehensive review of IW projects with several descriptions of intelligent wheel-
chairs. The main characteristics of an IW are [2] [4]: autonomous navigation with
safety, flexibility and obstacle avoidance capabilities; communication with others
devices such automatic doors and other wheelchairs and interaction with the user
using distinct types of devices such as joysticks, voice interaction, vision and other
sensor based controls like pressure sensors.
2.1
Intelligent Wheelchairs' Projects
The first project of an autonomous wheelchair for physical handicapped was proposed
by Madarasz in 1986 [5]. It was planned as a wheelchair with a micro-computer, a
digital camera and an ultra-sound scanner with the objective of developing a vehicle
that could move around in populated environments without human intervention. Hoy-
er and Holper [6] presented a modular control architecture for an omni-directional
wheelchair. The characteristics of NavChair [7], such as the capacity of following
walls and avoid obstacles by deviation are described in [7-9]. Miller and Slak [10]
[11] proposed the system Tin Man I with three operation modes: one individual
driving a wheelchair with automatic obstacles deviation; moving through-out a
track and moving to a point (x,y). This kind of chair evolved to Tin Man II which
included advanced characteristics such as storing travel information, return to the
starting point, follow walls, pass through doors and recharge battery. Wellman [12]
proposed a hybrid wheelchair equipped with two extra legs in addition to its four
wheels, to allow stair climbing and movement on rough terrain. FRIEND is a robot
