Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!lll-winken!uunet!portal!cup.portal.com!mmm
From: mmm@cup.portal.com (Mark Robert Thorson)
Newsgroups: sci.electronics
Subject: Re: Mechanical actuators
Message-ID: <19710@cup.portal.com>
Date: 20 Jun 89 19:34:06 GMT
References: <1436@xn.LL.MIT.EDU> <3249@kitty.UUCP>
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Organization: The Portal System (TM)
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rsteele@XN.LL.MIT.EDU (Rob Steele) says:

> I need a mechanical actuator to operate under microprocessor
> control.  Ideally it would be a solenoid that works off of
> 5 VDC and not much current.  The thing will be pulsed at
> around 7 Hz. with a 50% duty cycle and need not exert much
> mechanical force.  Am I dreaming?  What alternatives should
> I know about?

You don't mention the travel distance or the amount of force required.
A piezoceramic element might satisfy the actuation rate, wear, and power
consumption problems mentioned by Larry.  Perhaps he could suggest a
vendor for piezoceramic actuators?  (Maybe you could disassemble one of
those piezoceramic fans often sold as add-on equipment for Macintoshes
to cool the CPU chip.)

Another possibility is to use an audio speaker as your actuator (travel
distance and force would have to be very low).

Another possibility is to buy an old chart recorder from a junk shop
and use the actuator for the pen.