In this paper, we propose a modular navigation system that can be mounted on
a regular powered wheelchair to assist disabled children and the elderly with
autonomous mobility and shared-control features. The lack of independent
mobility drastically affects an individual's mental and physical health making
them feel less self-reliant, especially children with Cerebral Palsy and
limited cognitive skills. To address this problem, we propose a comparatively
inexpensive and modular system that uses a stereo camera to perform tasks such
as path planning, obstacle avoidance, and collision detection in environments
with narrow corridors. We avoid any major changes to the hardware of the
wheelchair for an easy installation by replacing wheel encoders with a stereo
camera for visual odometry. An open source software package, the Real-Time
Appearance Based Mapping package, running on top of the Robot Operating System
(ROS) allows us to perform visual SLAM that allows mapping and localizing
itself in the environment. The path planning is performed by the move base
package provided by ROS, which quickly and efficiently computes the path
trajectory for the wheelchair. In this work, we present the design and
development of the system along with its significant functionalities. Further,
we report experimental results from a Gazebo simulation and real-world
scenarios to prove the effectiveness of our proposed system with a compact form
factor and a single stereo camera