Title: Dimitar Stefanov
1Lecture 18
2Wheelchairs and Personal Transportation
- Some history
- Centuries ago transportation of the disabled on
hammocks slung between poles that were carried by
others (upper class people) - Wheelbarrow similar to these for transportation
of materials - During the Renaissance first wheelchairs arm
chairs with wheels placed on them (France) - Wooden wheelchairs until 1930
3- Franklin D. Roosevelt metal kitchen chairs
modified with wheels - Civil War First record of wheelchairs being
used in the United States. - 1907 First patent applied for a folding
wheelchair with a steel frame. - 1936 First single cross-brace steel wheelchair
patented by Everest Jennings Everest (mining
engineers), Jennings (engineer) - ErnestJennings first company for wheelchair
manufacture few years later - World War II steel-framed wheelchairs with 18
inch seat width - 1940s first powered wheelchairs, standard
manual wheelchairs adapted with automobile
starter motors and automobile battery - Rigid power wheelchair frame free space under
the seat (battery, controller, respirators, etc.)
4- 1948 Removable armrests introduced.
- 1950's Lightweight chairs developed for sports
use. - 1980's-present New composite frame materials
developed to further reduce the weight of chairs. - Personal automobile modified control of the
standard automobile - Microcars enlarged powered wheelchairs, speed
about 10 km/h - The first voice-activated power wheelchair was
used in 1984 by a student - 1995s omni-directional wheelchairs
5(No Transcript)
6- Categories of wheelchairs
- Manually powered
- Electrically powered
- 200 000 wheelchairs are sold annually within the
USA - 20 000 powered wheelchairs
Depot wheelchairs for institutional use,
several people may use one and the same wheelchair
One-arm-drive wheelchairs linkage connection of
the rear wheels
7Indoor and outdoor wheelchairs
Indoor wheelchairs short wheelbases, less
stable in lateral direction
- Wheelchairs, powered by the user
- Wheelchairs, powered by attendants
Ultra light wheelchairs
Sports wheelchairs
8Categories of wheelchairs (continue)
Stand-up wheelchairs
LifeStand, USA, http//www.lifestandusa.com/home.h
tm
9LEVO, Switzerland, http//www.levo.ch/
- Gas spring activated
- Electric activated
Stair-climbing wheelchairs
10Patient transfer systems
Vivax Medical, http//www.vivaxmedicalcorp.com/
Consists of a specially designed electric
(hospital type) bed and wheelchair. The
Vivax Mobility System has a transfer conveyor
system integrated into the bed frame which moves
the patient from the bed into a specially
designed wheelchair and back again. A built in
air support system provides true pressure relief
and a low-shear comfortable bed surface.
11Patient transfer systems
12Beach wheelchairs
http//www.beachwheelchair.com/
Scooters
Shoprider, http//www.dcc-shoprider.com/
13Frame design lightweight tubes
- Frame styles
- Box-frame wheelchairs (great strength and
rigidity) - Cantilever frame wheelchairs (the frame can act
as suspension fewer tubes)
Box-frame wheelchair
Cantilever frame wheelchair
14Materials
- Aluminum (6061 aluminum tubing) lightweight,
high corrosion resistance, - Steel (chromium- molybdenum alloy) easy to
welding, wall thickness 0.028 inches, diameter
0.25-1.25 inches - Titanium lightweight, strong require special
tooling, high cost - Composite materials (carbon fibers) extremely
strong and tough, lightweight
- Two basic styles of powered wheelchairs on the
market - The traditional style, and
- the platform-model powered chair (powered base
and a chair on it).
15Center of gravity (COG)
Located among the midline of the person and the
chair
16COG location
Seat width as narrow as possible usually 1
inch higher than the users hips
Frame angle
17Wheels and caster
Front casters from 50 to 200 mm in diameter for
manual wheelchairs for daily use.
- Pneumatic casters
- Polyurethane casters
Rear wheels wheels with large diameter
18Caster flutter
Rapid vibration on the front wheels
The caster flutter occurs when there is no enough
trail.