Re: Automatic Wheelchair Turntable

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

"Marc F Hult" <MFHult@xxxxxxxxxxxxxxxxxxxxx> wrote

<stuff snipped>

> >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
>
> A simple, compact approach would be a cable (or rope) and pulley/drum
> system. Two cables each wrap 2/3 to 3/4 of circumference of the turntable.
> One reversible or two uni-directional motors with drum -- or a hand
pull --
> turn the table. If friction/resistance of the table is made low enough, a
> motor may be unnecessary.

Yep.  That's sort of what I had in mind.  There's room in the corners for
one or even two motor assemblies.  I'm coming to realize the real problem
with any of these turntable and drive systems is that they add height to the
floor of the van.

The Entervans have a 10" dropped floor, but even that's almost not enough to
accomodate a person sitting in the van in a wheelchairs.

Well, that's the great value of Usenet - kicking around ideas to find the
weakspots or some previously undiscovered approach.  I'm beginning to like
the idea of a guidance system more than a turntable because the former
satisfies some collateral goals I have, namely remote chair status
monitoring.

--
Bobby G.