Analog relative movement sensor
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I'd like to monitor the slippage dynamics of a human head-mounted device
during rapid head movements. Slippage is largely due to skin movement
under the head strap, relative to the skull. Ideally, I'd like something
like a Hall-effect device mounted on the slipping head strap, sensing
position of a very small magnet taped to the skin. But these devices
produce digital pulses (not analog distance) when near the magnet. I
would prefer an analog output sensing relative movement of sensor and
reference maker over a small range of 5-10 mm. Any suggestions will be
welcome. I'm still scratching my (slipping) head over this one.
Dennis
during rapid head movements. Slippage is largely due to skin movement
under the head strap, relative to the skull. Ideally, I'd like something
like a Hall-effect device mounted on the slipping head strap, sensing
position of a very small magnet taped to the skin. But these devices
produce digital pulses (not analog distance) when near the magnet. I
would prefer an analog output sensing relative movement of sensor and
reference maker over a small range of 5-10 mm. Any suggestions will be
welcome. I'm still scratching my (slipping) head over this one.
Dennis
Comments
the manufacturer's name, but I believe that thru a web search you could
easily find it.
ACJacques
Dennis O'Leary wrote:
>
> I'd like to monitor the slippage dynamics of a human head-mounted device
> during rapid head movements. Slippage is largely due to skin movement
> under the head strap, relative to the skull. Ideally, I'd like something
> like a Hall-effect device mounted on the slipping head strap, sensing
> position of a very small magnet taped to the skin. But these devices
> produce digital pulses (not analog distance) when near the magnet. I
> would prefer an analog output sensing relative movement of sensor and
> reference maker over a small range of 5-10 mm. Any suggestions will be
> welcome. I'm still scratching my (slipping) head over this one.
> Dennis
>
>
>
> eGroups.com home: http://www.egroups.com/group/basicstamps
> http://www.egroups.com - Simplifying group communications
A wonderful supplier of Hall Effects and information is Allegro
Microsystems.
http://www.allegromicro.com/
Another is the Microswitch company, I don't have their web address.
Look at http://www.plano.com/mfrz.htm for all component manufacturers
web sites.
Jack Wilker
Honeywell and others make them . They are not expensive and very simple to use.
They are a bit power hungry so battery powered systems might be a challenge if
you need
tracking for a long time.
I have some very small magnets about 0.2" x 0.2" x .05 "( Rare earth type )
that could be used.
An alternate method that springs to mind is to use an optical pattern on the
skin and use
moire fringes to detect movement..
Date sent: Mon, 20 Mar 2000 20:25:33 -0300
From: "A.C.Jacques" <acjacques@i...>
To: basicstamps@egroups.com
Send reply to: basicstamps@egroups.com
Subject: [noparse][[/noparse]basicstamps] Re: Analog relative movement sensor
> There are Hall-effect sensors with analog output. I do not remember
> the manufacturer's name, but I believe that thru a web search you could
> easily find it.
> ACJacques
>
> Dennis O'Leary wrote:
> >
> > I'd like to monitor the slippage dynamics of a human head-mounted device
> > during rapid head movements. Slippage is largely due to skin movement
> > under the head strap, relative to the skull. Ideally, I'd like something
> > like a Hall-effect device mounted on the slipping head strap, sensing
> > position of a very small magnet taped to the skin. But these devices
> > produce digital pulses (not analog distance) when near the magnet. I
> > would prefer an analog output sensing relative movement of sensor and
> > reference maker over a small range of 5-10 mm. Any suggestions will be
> > welcome. I'm still scratching my (slipping) head over this one.
> > Dennis
> >
> >
> >
> > eGroups.com home: http://www.egroups.com/group/basicstamps
> > http://www.egroups.com - Simplifying group communications
>
>
>
> eGroups.com home: http://www.egroups.com/group/basicstamps
> http://www.egroups.com - Simplifying group communications
>
>
>
>
ron... the motor man...
Ronald Doctors
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