Anybody have manufacturers of piezo motion sensors? I need to detect and
correct single-axis changes, and these will do the job. So far I've
identified Murata. Any others you know of?
TIA.
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware & Software for Industry & R/C Hobbies
"Go fast, turn right, and keep the wet side down!"
==================================================================
Anybody have manufacturers of piezo motion sensors? I need to detect and
correct single-axis changes, and these will do the job. So far I've
identified Murata. Any others you know of?
TIA.
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware & Software for Industry & R/C Hobbies
"Go fast, turn right, and keep the wet side down!"
==================================================================
At 09:11 AM 4/10/97 +0100, you wrote:
>Futaba make solid state gyros that detect and give a servo error signal as
> output.
I'm looking for the actual piezo module itself, not a "rate gyro." There
are dozens of model helicopter-type gyros on the market - they aren't usable
in this application.
Thanks, though.
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware & Software for Industry & R/C Hobbies
"Go fast, turn right, and keep the wet side down!"
==================================================================
What general type of motion are you trying to sense? If it is not a
quick deflection type of motion then I am not aware of any reasonable
sensors short of doing absolute positioning and checking if your abs.
direction has changed. (or something pretty general like a compass..)
My understanding is the heli sensors are basically a weight on the end
of a piezo material used as a strain gague. They are not good at low
level changes. You can get the heli to be 'perfect' because you are
setting the average response to a lot of high level yaw pulses from the
engine. Take one perfect in hover, grab the tail (not really! not a
sane thing to do..) and slowly turn it. It will still compensate for
the engine, but it will not resist your motion at all. I'm don't know
anything that will (at a reasonable cost) short of a full gyro, so
what're you trying to do?
> I'm looking for the actual piezo module itself, not a "rate gyro." There
> are dozens of model helicopter-type gyros on the market - they aren't usable
> in this application.
Andy Kunz wrote:
>
> Anybody have manufacturers of piezo motion sensors? I need to detect and
> correct single-axis changes, and these will do the job. So far I've
> identified Murata. Any others you know of?
>
> TIA.
>
> Andy
Athough its not a piezoelectric type this may do the job.
Analog devices ADXL05J/A Accelerometer
Its in a 10 pin TO100 case. Output is +/- 1v for a +/- 5g input.
Capable of measuring uniform accelerations and vibrations up to 4kHz.
There is an application note in April 97 ELEKTOR ELECTRONICS
(UK addition) magazine.
The note does not give the address of a supplier.
If you find one let me know.
Andy Kunz wrote:
>
> Anybody have manufacturers of piezo motion sensors? I need to detect and
> correct single-axis changes, and these will do the job. So far I've
> identified Murata. Any others you know of?
>
> TIA.
>
> Andy
Further to my previous note on the ADXL05
Check out
www.analog.com/products/sheets/ADXL05.html
You can download the data sheet.
Maxim make too two axes accelerator sensors (free samples in our web
pages)
+------------------------------+-----------------------------------------+
| Tomas Vega | I try to live one day at a time, |
| Admin en unet.ve y lat.net | but lately several days have attacked |
| wolfmanKILLspamstealth.lat.net | me at once. |
+------------------------------+-----------------------------------------+
> Futaba make solid state gyros that detect and give a servo error signal as
> output.
>
> Kieran Sullivan
>
>
> ----------
> From: Andy Kunz[SMTP:.....montanaKILLspam.....FAST.NET]
> Sent: 10 April 1997 04:16
> To: EraseMEPICLISTspam_OUTTakeThisOuTMITVMA.MIT.EDU
> Subject: Piezo Motion Sensors
>
> Anybody have manufacturers of piezo motion sensors? I need to detect and
> correct single-axis changes, and these will do the job. So far I've
> identified Murata. Any others you know of?
>
> TIA.
>
> Andy
> ==================================================================
> Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
> Hardware & Software for Industry & R/C Hobbies
> "Go fast, turn right, and keep the wet side down!"
> ==================================================================
>
I think what Andy means is KISS..... I won't phrase to offend.
I've designed for some guy's doing simple vibration for sesimic detection
and the piezo's work well in detecting such in either microphonic or
displacement
(attaching a weight to the element). Although we found it hard to
repeat calibrations from unit to unit, it served their purpose. We
contacted several vendors, Murata, Kyocera, etc. who manufacture them,
but they only wanted to talk in thousand unit quanities.
We bought in hundred quanities from a company called ALL ELECTRONICS
CORPORATION, in California ( 800-826-5432)
http://www.allcorp.com/
They are one of many surplus dealers and have seemed to be able to
continually
have the one we used in stock. A hundred 1.4" diameter units can be
purchased for $65.00. They of course will sell in single units for
a buck.
I have also used the Analog Devices the others have suggested and they
are great, but expensive as compared to the piezo. The impedance
of the units are such that you can just about read them with a 16c7X device,
but they really need to be buffered with a amp or use a seperate A/D. I
used a LTC1286 A/D to get 12 bits of accuracy.
Let me know if I can help further.
Andy Kunz wrote:
At 09:11 AM 4/10/97 +0100, you wrote:
>Futaba make solid state gyros that detect and give a servo error
signal as > output.
I'm looking for the actual piezo module itself, not a "rate
gyro."
There
are dozens of model helicopter-type gyros on the market - they aren't usable
in this application.
Thanks, though.
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware &
Software
for Industry & R/C Hobbies
"Go fast, turn right, and
keep the wet side down!"
==================================================================
At 03:29 AM 4/11/97 -0400, you wrote:
>What general type of motion are you trying to sense? If it is not a
Quick and jerky or audio-level and down vibrations, typically. Rotational
motion mostly, not linear, although there will be linear components I'm sure.
The sensors used in heli gyros will work fine (that was what I started
sensing with). A heli gyro is _way_ too insensitive in its output. I need
to respond to millisecond changes (vibrational) continuously, not at the
50-60 Hz of a heli gyro.
>My understanding is the heli sensors are basically a weight on the end
>of a piezo material used as a strain gague. They are not good at low
>level changes.
That varies greatly from mfg to mfg, and is why heli pilots will find
different companies' that are better than the competition.
>sane thing to do..) and slowly turn it. It will still compensate for
>the engine, but it will not resist your motion at all.
This is actually programmable. The heli gyro sensor I started with was
able to detect far less than a degree per second. It didn't respond
because the program didn't accumulate the error very well (the I part of PID).
>I'm don't know
>anything that will (at a reasonable cost) short of a full gyro, so
>what're you trying to do?
Camera mount stabilizer with other applications.
Accelerometers are better for linear displacements, not rotational.
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware & Software for Industry & R/C Hobbies
"Go fast, turn right, and keep the wet side down!"
==================================================================
At 03:19 PM 4/12/97 -0400, you wrote:
>At 03:29 AM 4/11/97 -0400, you wrote:
>>What general type of motion are you trying to sense? If it is not a
>
>Quick and jerky or audio-level and down vibrations, typically. Rotational
>motion mostly, not linear, although there will be linear components I'm sure.
Linear components wont affect an image, just rotational, I think.
>>My understanding is the heli sensors are basically a weight on the end
>>of a piezo material used as a strain gague. They are not good at low
>>level changes.
No, their vibrating prisms or tuning forks, that behave much like spinning
gyroscopes.
>
>That varies greatly from mfg to mfg, and is why heli pilots will find
>different companies' that are better than the competition.
Also has to do with signal conditioning/trasfer function past the sensor.
>Camera mount stabilizer with other applications.
I wonder what the new camcorders use? If you rev. eng. one let us know!
They stabilize the image, not the camera; there are no motion
sensors in the camera, just a lot of really fast logic.
The camera only displays in the viewfinder (and records to tape) a
small window within its field of view. By analyzing the entire
overscanned image it "sees", it can shift that inner window around
in the field of view so as to eliminate high-frequency vibrations of
that window.
The technique has some problems... It can be confused by images
which are changing very quickly (e.g., an extreme close-up of a
rapidly-oscillating piece of machinery) or by really low-contrast
images.
It also has problems with deliberate pans and tilts... Because it
"low-pass filters" the movement of the image, the view through the
viewfinder lags behind the actual pan/tilt movement a little. This
is disconcerting at first... Some camera operators never get used to
it and it makes them feel sorta queasy.
-Andy
=== Andrew Warren - @spam@fastfwdKILLspamix.netcom.com
=== Fast Forward Engineering - Vista, California
===
=== Custodian of the PICLIST Fund -- For more info, see:
=== www.geocities.com/SiliconValley/2499/fund.html
>I wonder what the new camcorders use? If you rev. eng. one let us know!
Murata makes their GyroStar line especially for cameras. Turns out that at
least one of the model heli gyros I examined doing research uses the exact
same module (part number). The app notes I was given by the Murata rep are
for use in a camera. I'm looking at a camera platform, though.
I'm looking for another source, though.
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware & Software for Industry & R/C Hobbies
"Go fast, turn right, and keep the wet side down!"
==================================================================
>
> At 03:29 AM 4/11/97 -0400, you wrote:
> >What general type of motion are you trying to sense? If it is not a
>
> Quick and jerky or audio-level and down vibrations, typically. Rotational
> motion mostly, not linear, although there will be linear components I'm sure.
>
> The sensors used in heli gyros will work fine (that was what I started
> sensing with). A heli gyro is _way_ too insensitive in its output. I need
> to respond to millisecond changes (vibrational) continuously, not at the
> 50-60 Hz of a heli gyro.
>
> >My understanding is the heli sensors are basically a weight on the end
> >of a piezo material used as a strain gague. They are not good at low
> >level changes.
>
> That varies greatly from mfg to mfg, and is why heli pilots will find
> different companies' that are better than the competition.
>
> >sane thing to do..) and slowly turn it. It will still compensate for
> >the engine, but it will not resist your motion at all.
>
> This is actually programmable. The heli gyro sensor I started with was
> able to detect far less than a degree per second. It didn't respond
> because the program didn't accumulate the error very well (the I part of PID).
>
> >I'm don't know
> >anything that will (at a reasonable cost) short of a full gyro, so
> >what're you trying to do?
>
> Camera mount stabilizer with other applications.
>
> Accelerometers are better for linear displacements, not rotational.
>
> Andy
>
Why not stick 3 weights to the membranes of three piezo transducers
and arrange them in a XYZ config? Amplify and read the voltages.
--
Friendly Regards
Tjaart van der Walt KILLspamtjaartKILLspamwasp.co.za
_____________________________________________________________
| Another sun-deprived R&D Engineer slaving away in a dungeon |
| WASP International http://wasp.co.za |
| GSM and GPS value-added applications |
| Voice : +27-(0)11-622-8686 | Fax : +27-(0)11-622-8686 |
|_____________________________________________________________|
>They stabilize the image, not the camera; there are no motion
>sensors in the camera, just a lot of really fast logic.
>
I bet horizontal or yaw vibrations are canceled by delaying the pulses (or
decreasing thier frequency) of the CCD's horizontal row-clock, and verticle
or pitch vibrations are compensated with the CCD's verticle sync pulses.
>The technique has some problems... It can be confused by images
>which are changing very quickly (e.g., an extreme close-up of a
>rapidly-oscillating piece of machinery) or by really low-contrast
>images.
A pulsing strobe also tends to foul up certain guided missles. Maybe the
CCD's samples the strobe, and creates beats in the passband of a PLL low
pass filter of the control system stabilizing the image. I wonder if they
rely on high contrast to provide a signal to phase lock on, or if they
inject a pilot tone & filter it out of the video later?
>Murata makes their GyroStar line especially for cameras. Turns out that at
>least one of the model heli gyros I examined doing research uses the exact
>same module (part number). The app notes I was given by the Murata rep are
>for use in a camera. I'm looking at a camera platform, though.
>I'm looking for another source, though.
>
Well, there's Systron Donner's Gyro Chip. I've heard say its better &
cheaper. Tooo expensive? I cant believe the price of gyros, and thier
scarcity. I wonder when Analog Devices, Motorola, or another sensor
manufacturer will produce a decent micro-machined gyro, similar to the ADXL
accelerometer's. I read article a few years back that said they're past due
by now.
I tried making my own piezo-gyro awhile back, glueing a resonant nail
segment to a $1 piezo disk, the electrodes of which I segmented to drive it
in its 2nd mode, around 8KHz. Found it was sensitive to angular momentum,
but unfortunatly, to minute temperature changes, any vibrations, or even a
subtle change in pressure on the thin copper wires and disk mounting-such as
touching the circuit board it was on. It even produced a chaotic vibration
mode as the adhesive failed. That was enough for me!
>I tried making my own piezo-gyro awhile back, glueing a resonant nail
>segment to a $1 piezo disk, the electrodes of which I segmented to drive it
>in its 2nd mode, around 8KHz. Found it was sensitive to angular momentum,
>but unfortunatly, to minute temperature changes, any vibrations, or even a
>subtle change in pressure on the thin copper wires and disk mounting-such as
>touching the circuit board it was on. It even produced a chaotic vibration
>mode as the adhesive failed. That was enough for me!
You ought to get a $15 Murata and see what all they did to take care of all
those complaints. All except temperature, which is traditionally handled
externally.
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware & Software for Industry & R/C Hobbies
"Go fast, turn right, and keep the wet side down!"
==================================================================
>and see what all they did to take care of all
>those complaints. All except temperature, which is traditionally handled
>externally.
>
>Andy
>
>==================================================================
>Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
> Hardware & Software for Industry & R/C Hobbies
> "Go fast, turn right, and keep the wet side down!"
>==================================================================
>
>
In a message dated 97-04-16 09:53:18 EDT, you write:
>I bet horizontal or yaw vibrations are canceled by delaying the pulses (or
>decreasing thier frequency) of the CCD's horizontal row-clock, and verticle
>or pitch vibrations are compensated with the CCD's verticle sync pulses.
This may be effective if you are not using the CCD at full speed (i.e.
integration time equal to only the time to shift out data). If you are,
changing any of the clocking times will effect integration time, and
therefore, image intensity. I once used a CCD where I clocked data out at
rated speed (12MHz, I think) but let the CCD integrate for an adjustable time
period after the data was finished clocking out. This worked quite well to
improve the range of image intensities we were able to view.
Mark A. Corio
Rochester MicroSystems, Inc.
200 Buell Road, Suite 9
Rochester, NY 14624
Tel: (716) 328-5850 --- Fax: (716) 328-1144 http://www.frontiernet.net/~rmi/
***** Designing Electronics For Research & Industry *****
> You ought to get a $15 Murata and see what all they did to take care of all
> those complaints. All except temperature, which is traditionally handled
> externally.
>
> Andy
>
$15 Murata ???. I asked them for quotes on a quantity of 1000 and they
quoted $35 per piece. Where did you get these #15 Piezo's, I'd like to
get a couple!
Thanks
Jay
---
Jay Shroff
Product Development 810-377-7869
Fanuc Robotics fax: 810-377-7363
Auburn Hills MI
>$15 Murata ???. I asked them for quotes on a quantity of 1000 and they
>quoted $35 per piece. Where did you get these #15 Piezo's, I'd like to
>get a couple!
Andy
======================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865 USA
Electronics for Industry & R/C Hobbyists
"Go fast, turn right, and keep the wet side down!"
======================================================================
>$15 Murata what? you mean a $150 gyrostar? or a data sheet?
They have GyroStar products in the $15 range, $12 or less in quantity. I
doubt they would have given me 10 free samples if they were $150 each.
Andy
======================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865 USA
Electronics for Industry & R/C Hobbyists
"Go fast, turn right, and keep the wet side down!"
======================================================================
Andy Kunz wrote:
>
> >$15 Murata what? you mean a $150 gyrostar? or a data sheet?
>
> They have GyroStar products in the $15 range, $12 or less in quantity. I
> doubt they would have given me 10 free samples if they were $150 each.
>
I'd need only two one for starting my project .
where can I find murata on the web ?
the chipdir contains only the name :(
They rep them. Buy from your local Future/FAI office
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware & Software for Industry & R/C Hobbies
"Go fast, turn right, and keep the wet side down!"
==================================================================
In a message dated 97-04-17 12:07:33 EDT, you write:
>.
>
>Did you use MOS drivers for the CCD? Was it a Sony 016AL???
I don't recall what drivers we used (I no longer work there), but I do
remember we were stressing them beyond manufacturer's ratings. The CCD was a
Kodak sensor but I don't see much difference in the Sony parts and others, so
it should work the same.
Mark A. Corio
Rochester MicroSystems, Inc.
200 Buell Road, Suite 9
Rochester, NY 14624
Tel: (716) 328-5850 --- Fax: (716) 328-1144 http://www.frontiernet.net/~rmi/
***** Designing Electronics For Research & Industry *****
Andy I sent this to you a week ago, maybe you didn't get it from the responses
I've been reading.
I've designed for some guy's doing simple vibration for sesimic detection
and the piezo's work well in detecting such in either microphonic or
displacement
(attaching
a weight to the element). Although we found it hard to repeat
calibrations
from unit to unit, it served their purpose. We contacted several
vendors, Murata,
Kyocera, etc. who manufacture them, but they only wanted to talk in thousand
unit quanities.
We bought in hundred quanities from a company called ALL ELECTRONICS
CORPORATION, in California ( 800-826-5432)
http://www.allcorp.com/
They are one of many surplus dealers and have seemed to be able to
continually
have the one we used in stock. A hundred 1.4" diameter units can be
purchased for
$65.00. They of course will sell in single units for a buck.
I have also used the Analog Devices the others have suggested and they
are great, but expensive as compared to the piezo. The impedance
of the units are such that
you can just about read them with a 16c7X device, but they really need
to be buffered with a amp or use a seperate A/D. I used a LTC1286 A/D to
get 12 bits of
accuracy.
Let me know if I can help further.
Andy Kunz wrote:
>I'd need only two one for starting my project
. >where can I find murata on the web ? >the chipdir contains only the name :(
They rep them. Buy from your local Future/FAI office
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware &
Software
for Industry & R/C Hobbies
"Go fast, turn right, and
keep the wet side down!"
==================================================================
FAST.NET]
