REFLECTOR:Re: RVDT/LVDT Conditioner
Brian Michalk
reflector@tvbf.org
Thu, 8 Apr 2004 11:48:06 -0500
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Most likely it's a Murata solid state gyro.
It is based on the coriolis effect, where a microscopic fork vibrates in a
plane. As the device is rotated, the vibration wants to stay in the same
plane of vibration. This is sensed as a deflection by using capacitane (I
think) to detect if the fork is vibrating near one of the capacitance
sensors.
The problem with these is that they have pretty bad drift compared to a
mechanical gyro. It's a problem with many of the solid state gyros, except
for the FOG (fiber optic gyro). The drift can be compensated for somewhat
with accelerometers, but for long term stability, they are not so good.
Now, couple that with magnetic heading, or GPS heading and I think these
cheap gyros could make a decent wing leveler.
These can be had for about $25 each, if I remember correctly.
-----Original Message-----
From: reflector-admin@tvbf.org [mailto:reflector-admin@tvbf.org]On Behalf
Of HYTEC45@aol.com
Sent: Thursday, April 08, 2004 9:25 AM
To: reflector@tvbf.org
Subject: Re: REFLECTOR:Re: RVDT/LVDT Conditioner
In a message dated 4/7/2004 6:38:48 PM Pacific Standard Time,
jewen@comporium.net writes:
I am planning on bringing these
signals into a PLC so I can program a low cost autopilot (wings level,
pitch
and alt hold.)
I don't know squat about this stuff as my brain is as full as it can get.
If I want to learn something new, I have to forget something, but as a
stupid question to the electronic guys. My son and I play with RC
helicopters and such and I have noticed that they offer on board autopilots
(bacon savers) for them. I know nothing about them except for adds I see in
RC rags and they are small.
TEC
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<BODY style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial; BACKGROUND-COLOR: =
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<DIV><SPAN class=3D200084116-08042004>Most likely it's a Murata solid =
state=20
gyro.</SPAN></DIV>
<DIV><SPAN class=3D200084116-08042004></SPAN> </DIV>
<DIV><SPAN class=3D200084116-08042004>It is based on the coriolis =
effect, where a=20
microscopic fork vibrates in a plane. As the device is =
rotated, the=20
vibration wants to stay in the same plane of vibration. This is =
sensed as=20
a deflection by using capacitane (I think) to detect if the fork is =
vibrating=20
near one of the capacitance sensors.</SPAN></DIV>
<DIV><SPAN class=3D200084116-08042004></SPAN> </DIV>
<DIV><SPAN class=3D200084116-08042004>The problem with these is that =
they have=20
pretty bad drift compared to a mechanical gyro. It's a problem =
with many=20
of the solid state gyros, except for the FOG (fiber optic gyro). =
The drift=20
can be compensated for somewhat with accelerometers, but for long term=20
stability, they are not so good. Now, couple that with magnetic =
heading,=20
or GPS heading and I think these cheap gyros could make a decent wing=20
leveler.</SPAN></DIV>
<DIV><SPAN class=3D200084116-08042004></SPAN> </DIV>
<DIV><SPAN class=3D200084116-08042004>These can be had for about $25 =
each, if I=20
remember correctly.</SPAN></DIV>
<DIV><SPAN class=3D200084116-08042004></SPAN> </DIV>
<DIV><SPAN class=3D200084116-08042004></SPAN> </DIV>
<BLOCKQUOTE dir=3Dltr=20
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solid; MARGIN-RIGHT: 0px">
<DIV class=3DOutlookMessageHeader dir=3Dltr align=3Dleft><FONT=20
face=3DTahoma>-----Original Message-----<BR><B>From:</B>=20
reflector-admin@tvbf.org [mailto:reflector-admin@tvbf.org]<B>On Behalf =
Of=20
</B>HYTEC45@aol.com<BR><B>Sent:</B> Thursday, April 08, 2004 9:25=20
AM<BR><B>To:</B> reflector@tvbf.org<BR><B>Subject:</B> Re: =
REFLECTOR:Re:=20
RVDT/LVDT Conditioner<BR><BR></FONT></DIV>
<DIV>
<DIV>In a message dated 4/7/2004 6:38:48 PM Pacific Standard Time,=20
jewen@comporium.net writes:</DIV>
<BLOCKQUOTE=20
style=3D"PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px =
solid"><FONT=20
face=3DArial>I am planning on bringing these<BR>signals into a PLC =
so I can=20
program a low cost autopilot (wings level, pitch<BR>and alt=20
hold.) </FONT></BLOCKQUOTE></DIV>
<DIV>I don't know squat about this stuff as my brain is as full as it =
can=20
get. If I want to learn something new, I have to forget =
something, but=20
as a stupid question to the electronic guys. My son and I =
play with=20
RC helicopters and such and I have noticed that they offer on =
board=20
autopilots (bacon savers) for them. I know nothing about them =
except for=20
adds I see in RC rags and they are small.</DIV>
<DIV> </DIV>
<DIV>TEC </DIV></BLOCKQUOTE></BODY></HTML>
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