Re: Automatic Wheelchair Turntable

["Wayne Lundberg" <Waynelund@xxxxxxxxxxxxxxxx>]

"Robert Green" <ROBERT_GREEN1963@xxxxxxxxx> wrote in message
news:_rydnR8CpccKQ6beRVn-hw@xxxxxxxxxx
> I just got my Dad a wheelchair van with an electric ramp but we've hit a
> snag.  There's not enough room to turn the wheelchair around inside the
van.
> If he goes in forward, he has to come out backwards.
>
> I toyed with some automatic guidance systems to make sure the backup
> procedure didn't run him off the ramp, but I don't think that's a wise
> solution.
>
> I decided that since there's almost a 4X4 foot flat area inside the van, I
> would take a 4x4 sheet of 3/4" plywood and make a turntable on the van
> floor.  When he transfers to the driver's seat, I want the turntable to
> automatically rotate 180 degrees to position the powerchair so that it
will
> go down the ramp front first.
>
> I'm not sure how I would contstruct and power the turntable, however.
It's
> got to be as thin as practical - there's very little extra headroom in
these
> types of vans and it's got to have some sort of autodetection of exactly
180
> degrees - probably some sort of limit switch.
>
> Should I rout a channel in the outside of the circular-cut plywood panel
to
> run a belt?  That why I could mount a motor in the corner and still have a
> pretty low overall height.  Sort of how some belt-driven record turntables
> are designed.  I could also cover the ends of the belt that are likely to
> drag loose seat belts into the works pretty thoroughly with a motor
mounted
> in the corner.
>
> Does anyone know if they make commerical turntables for this purpose?  As
> much research as we did on vans, lifts, ramps and options, it kind of
floors
> me that we didn't realize there would be a "wrong way out" problem.  Just
a
> reminder to always model things, even if they seem trivial.
>
> Well, any suggestions, inputs, discussion or ideas where to post for good
> feedback will be appreciated!
>
> (posted to:  comp.home.automation & alt.support.wheelchairs)
>
> --
> Bobby G.
.
Some years ago we had an exercise device consisting of lazy Susan bearing
ring that would simply not quit no matter how heavy the person doing the
movements. The same lazy Suzan innards is a regular sale item at any Home
Depot. Also circular pieces of plywood to which you might add some sliding
door rollers on the edges to keep balance. You should be able to make a
device, manually controlled, with manual locks for less than $200 if you
have any skills at all with skill saw and drill.

Wayne