Domain

Litreature Survey

The number of physically disabled people in society have greatly aggravated in the past decade as a result of increasing war and aging population. The demand for the improving the quality of life of such people has therefore been a major concern. The largest problem faced by all handicapped, paralyzed and disabled is immobility and the need of an artificial means of transport. The common and largely used solution in this regard is a wheelchair, but a wheelchair is associated with a number of disadvantages. The amount of user effort required to pull and push the wheels, lack of security and stability prevents a physically weak user from operating a wheelchair on his own and makes him depend on another person's help. With the busy life styles of people in today's society, this can be very in-affordable. Users who cannot use their arms have absolutely no way of using a traditional wheelchair..

Research Gap

Previous researches in this field have led to the invention of several technical products that offer some advantage over traditional wheelchairs. However none of them were a complete solution as they had a number of drawbacks and limitations. Computer controlled wheelchair systems were developed which enable users to control wheelchair navigation through software running on a connected laptop. The user is required to afford a laptop to operate this type of wheelchair and is thus cost-ineffective. The user is also required to have sufficient computer knowledge. Wheelchair systems that focused on severely disabled people were developed using sophisticated technologies and expensive hardware. Examples are head gesture controlled wheelchairs which trigger wheelchair navigation through head movements, eye controlled wheelchairs which control wheelchair actions through the movements of the eye and forehead signal controlled wheelchairs, which trigger movement according to the user's facial expression. The problem with these products is that the sophisticated hardware and software used, makes them very expensive and in-affordable. Voice controlled wheelchairs were also developed, but they too require a laptop to run the application software.

The Problem Addressed

Our aim therefore, was to build a wheelchair system which will effectively overcome the problems associated with traditional wheelchairs and enable a user to use it without the aid of another person, irrespective of his physical condition. The wheelchair system should also be a low cost product, so that many will have the previledge of affording one, unlike some of the sophisticated wheelchair products in today's market.

The solution which we have successfully developed, is the Intelligent Wheelchair, a low cost semiautonomous wheelchair system which is developed as an embedded system that requires no computer. Yet it will overcome the problems of traditional wheelchairs and enable the user to use it by himself.

The intelligent wheelchair facilitates control methods which require the least amount of human effort. The user can move the wheelchair by two simple ways, either by moving a joystick or using voice commands. Voice controlled navigation enables a user who can not use his hands to use the wheelchair. The intelligent wheelchair provides maximum security for its user. The motion path of the wheelchair is scanned through ultrasonic sensors and avoids any obstacles or falloffs. The user is thus protected even if a misjudgment is made. The wheelchair is also equipped with a wireless communication facility, which will enable the user to have bidirectional communication with a remote PC user/administrator in case of an emergency. The product is developed by modifying a traditional wheelchair and is developed as an embedded system. A laptop or computer is not required. It is therefore very cost effective in comparison to other technical wheelchair products and researches.