Powered Wheelchair Anu

8/2/2019 Powered Wheelchair Anu

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POWEREDWHEELCHAIR

Presented by,

ANU MARIA PAUL

S7 BME

NO: 3


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Wheelchair

wheelchairs were designed to provide the veteransome mobility within the hospital and home.

Mobility among people with disabilities varies.

Mobility is more of a functional limitation than adisability related condition.

There are two basic classes of wheelchairs:

1. manually powered

2. externally powered


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Powered Wheelchairs

A power wheelchair may provide greatermobility.

It may be best to suggest a power wheelchair forlonger excursions.

Powered wheelchair bases can be classified as

1. rear-wheel drive (RWD)

2. mid-wheel drive (MWD)

3. front-wheel drive (FWD)


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RWD

In RWD power bases, the drive wheels are behind the

users center of gravity and the casters are in the

front. RWD systems are the traditional design.

Advantage: RWD systems is its predictable drive

characteristic and stability.

Drawback: RWD system is its maneuverability in tight

areas because of a larger turning radius.


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MWD

In MWD power bases, the drive wheels are directly

below the users CoG and generally have a set of

casters or antitippers in front and rear of the drive

wheels.

Advantage :MWD system is of smaller turning radius

to maneuver in tight spaces.

Disadvantage: has a tendency to rock or pitch forward,

especially with sudden stops or fast turns.


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FWD

A FWD power base has the drive wheels in front of theusers CoG, and it tends to be quite stable and

provides a tight turning radius.

Advantage: may climb obstacles or curbs more easilyas the large front wheels hit the obstacle first.

Disadvantage : has more rearward CoG; therefore,the system may tend to fishtail and be difficult todrive in a straight line, especially on unevensurfaces.


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Parts Of Powered wheelchair

Power Wheelchair Interfaces

Proportional Position-Sensing Joystick

Switched Inputs Force-Sensing Control

Voice Control


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Switched Inputs

Durability is a primary consideration when

choosing a control interface for a person with

this disability.

Switch array can be mounted on the

wheelchair tray and accessed by the hand,

head, and chin.

Typically yields much lower performance than

other proportional joysticks.


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Force-Sensing Control


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CONTD

An isometric Joystick does not use spherical ororthogonal pivots on the base of the stick; the

shaft and handle are permanently fixed in a

vertical position. The force vector exerted bythe operators hand becomes the magnitude

and direction of input.

The isometric was superior to the position-

sensing joystick for driving straight and for

driving in a circle.


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Voice Control

The voice control wheelchair system requires a

voice processor that converts a preselected set

of sounds spoken by the user into

corresponding signals a computer can

recognize. The sounds of commands are

preprogrammed into the computer during a

training session. These commands serve as thebasis for comparison with the users command

during use of the wheelchair.


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Powered wheelchair velocity control

scheme.


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Thank you

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Powered Wheelchair Anu