tension in fish line
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Posts: 46,084
I have a project where I need to monitor tension in a fish line, and
the sensor has to fit in a small cylinder attached underwater in the
line. Any ideas? I want to keep the mechanical complexity to a
minimum. The cylinder will also contain a small PIC12C data logger
to record the tension profile.
It occurs that something like this might be useful to monitor the
speed of a boat, by recording the drag tension.
-- Tracy
the sensor has to fit in a small cylinder attached underwater in the
line. Any ideas? I want to keep the mechanical complexity to a
minimum. The cylinder will also contain a small PIC12C data logger
to record the tension profile.
It occurs that something like this might be useful to monitor the
speed of a boat, by recording the drag tension.
-- Tracy
Comments
Break the line, and attach both broken ends to the arms of a V-shaped
metal spring, the the base of the V attached to the cylinder. Mount a
small magnet on one arm of the V and an Allegro linear Hall effect
sensor on the other arm. With the right thickness, the spring should
follow Hooke's Law F = -kx, where x is linear separation of the two arms
of the V, and F is tensile force.
Dennis
Original Message
From: Tracy Allen [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=xIibEhchs9xCMD6xE1rNqn42NZMg5gRk_UiyHFiR6pklhh_So81zZi11R66WnLQnhS3fL3woYGKOeLnSpGEI]tracy@e...[/url
Sent: Thursday, January 10, 2002 9:17 AM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] tension in fish line
I have a project where I need to monitor tension in a fish line, and
the sensor has to fit in a small cylinder attached underwater in the
line. Any ideas? I want to keep the mechanical complexity to a
minimum. The cylinder will also contain a small PIC12C data logger
to record the tension profile.
It occurs that something like this might be useful to monitor the
speed of a boat, by recording the drag tension.
-- Tracy
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mount a small magnet on the line, and a hall-effect sensor at the end, you
could read the stretch in the line which would be relative to the tension on
it.
From: "Tracy Allen" <tracy@
> I have a project where I need to monitor tension in a fish line, and
> the sensor has to fit in a small cylinder attached underwater in the
> line. Any ideas? I want to keep the mechanical complexity to a
> minimum. The cylinder will also contain a small PIC12C data logger
> to record the tension profile.
>
> It occurs that something like this might be useful to monitor the
> speed of a boat, by recording the drag tension.
>
> -- Tracy
How about a strain gauge through an ADC to your data logger?
Tim
At 09:17 AM 1/10/2002 -0800, you wrote:
>I have a project where I need to monitor tension in a fish line, and
>the sensor has to fit in a small cylinder attached underwater in the
>line. Any ideas? I want to keep the mechanical complexity to a
>minimum. The cylinder will also contain a small PIC12C data logger
>to record the tension profile.
>
>It occurs that something like this might be useful to monitor the
>speed of a boat, by recording the drag tension.
>
> -- Tracy
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject and
>Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
> I have a project where I need to monitor tension in a fish line, and
> the sensor has to fit in a small cylinder attached underwater in the
> line. Any ideas? I want to keep the mechanical complexity to a
> minimum. The cylinder will also contain a small PIC12C data logger
> to record the tension profile.
How about a load cell that's read by the data logger? I worked on an
application a long time ago where one was used in conjunction with a large
crane for weighing things. A much scaled down version could be calibrated to
measure the line tension.
Tim
>the sensor has to fit in a small cylinder attached underwater in the
>line. Any ideas? I want to keep the mechanical complexity to a
>minimum. The cylinder will also contain a small PIC12C data logger
>to record the tension profile.
>
>It occurs that something like this might be useful to monitor the
>speed of a boat, by recording the drag tension.
>
> -- Tracy
Maybe one of the Force Sensing Resistor devices? I think there
are issues with hysteresis and you'd probably have to
temperature compensate it, but it could be small & simple.
Reg
the string and the syringe pulls a vacuum you would need a spring in the
syringe.
Original Message
From: "Tracy Allen" <tracy@e...>
To: <basicstamps@yahoogroups.com>
Sent: January 10, 2002 9:17 AM
Subject: [noparse][[/noparse]basicstamps] tension in fish line
| I have a project where I need to monitor tension in a fish line, and
| the sensor has to fit in a small cylinder attached underwater in the
| line. Any ideas? I want to keep the mechanical complexity to a
| minimum. The cylinder will also contain a small PIC12C data logger
| to record the tension profile.
|
| It occurs that something like this might be useful to monitor the
| speed of a boat, by recording the drag tension.
|
| -- Tracy
|
| To UNSUBSCRIBE, just send mail to:
| basicstamps-unsubscribe@yahoogroups.com
| from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
|
|
| Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
|
|
boat be workable?
>Dennis:
>Break the line, and attach both broken ends to the arms of a V-shaped
>metal spring, the the base of the V attached to the cylinder. Mount a
>small magnet on one arm of the V and an Allegro linear Hall effect
>sensor on the other arm.
>FalconW:
>Fishing line has approximately a 2 to 1 stretch ratio, so if you were to
>mount a small magnet on the line, and a hall-effect sensor at the end, you
>could read the stretch in the line
I like the magnet idea. It would be neat to simply attach the magnet
to a stretchy piece of line and monitor its motion in relation to a
detector fixed in the cylinder. The magnet might run in a guide tube
alongside the main cylinder. It doesn't require too much accuracy.
>Tim M:
>How about a strain gauge through an ADC to your data logger?
>Tim McD:
>How about a load cell that's read by the data logger?
I am not sure what kind of strain gage to use or what to fasten it
to. Does anybody know of a "strain gage" like a little piece of
string with two loops at the ends? I'm afraid there may not be room
inside this cylinder for the necessary amplifier. It barely holds
the existing circuits and a coin cell.
>Reg:
>Maybe one of the Force Sensing Resistor devices? I think there are
>issues with hysteresis and you'd probably have to temperature
>compensate it, but it could be small & simple.
That is actually what we used in a desktop prototype, but they
operate in compression so it would need some lever action or an FSR
in the shape of a small donut that we could bring a bolt up through
to change tension to compression. But I can't find much variety in
off the shelf FSRs. Is there some other material we could use like
that?
>Larry:
>Maybe something like a syringe with a pressure transducer on the end pull
>the string and the syringe pulls a vacuum you would need a spring in the
>syringe.
hmmm. Maybe something like a gel-filled bellows.
>Michael:
>Is it essential to put the electronics underwater? Would a system
>aboard the boat be workable?
I think it does have to be underwater. It will monitor a couple of
other parameters at depth.
-- Thanks for the great ideas, and I'm still fishing!
Tracy
other stretchy tubing used as a strain gauge. Resistance changes as
the tube stretches and diameter changes.
Bob Nienhuis
nienhuis@w...
At 09:49 PM 1/10/02 -0800, you wrote:
>Thank's for the ideas and comments!
>
> >Dennis:
> >Break the line, and attach both broken ends to the arms of a V-shaped
> >metal spring, the the base of the V attached to the cylinder. Mount a
> >small magnet on one arm of the V and an Allegro linear Hall effect
> >sensor on the other arm.
>
> >FalconW:
> >Fishing line has approximately a 2 to 1 stretch ratio, so if you were to
> >mount a small magnet on the line, and a hall-effect sensor at the end, you
> >could read the stretch in the line
>
>I like the magnet idea. It would be neat to simply attach the magnet
>to a stretchy piece of line and monitor its motion in relation to a
>detector fixed in the cylinder. The magnet might run in a guide tube
>alongside the main cylinder. It doesn't require too much accuracy.
>
> >Tim M:
> >How about a strain gauge through an ADC to your data logger?
>
> >Tim McD:
> >How about a load cell that's read by the data logger?
>
>I am not sure what kind of strain gage to use or what to fasten it
>to. Does anybody know of a "strain gage" like a little piece of
>string with two loops at the ends? I'm afraid there may not be room
>inside this cylinder for the necessary amplifier. It barely holds
>the existing circuits and a coin cell.
>
> >Reg:
> >Maybe one of the Force Sensing Resistor devices? I think there are
> >issues with hysteresis and you'd probably have to temperature
> >compensate it, but it could be small & simple.
>
>That is actually what we used in a desktop prototype, but they
>operate in compression so it would need some lever action or an FSR
>in the shape of a small donut that we could bring a bolt up through
>to change tension to compression. But I can't find much variety in
>off the shelf FSRs. Is there some other material we could use like
>that?
>
> >Larry:
> >Maybe something like a syringe with a pressure transducer on the end pull
> >the string and the syringe pulls a vacuum you would need a spring in the
> >syringe.
>
>
>hmmm. Maybe something like a gel-filled bellows.
>
> >Michael:
> >Is it essential to put the electronics underwater? Would a system
> >aboard the boat be workable?
>
>
>I think it does have to be underwater. It will monitor a couple of
>other parameters at depth.
>
>
> -- Thanks for the great ideas, and I'm still fishing!
> Tracy
>
>
>
>
>
>
>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject and
>Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
art. I'll give it a shot anyway.
Imagine a cylinder stuck vertically on a fixed base. Attached to the
bottom is one end of a spring which is much shorter than the
length of the cylinder. The top end of the spring has a loop. The
fishing line passes over one side of the cylinder, down through the
loop in the spring and up over the other side of the cylinder.
The position of the top of the spring is proportional to the tension
on the fishing line. Attach that to the slider of a linear pot, measure
and do some sums.
The cylinder is just to illustrate the concept. Take a couple of
fishing rod roller guides and fold to suit.
Cheap and simple and doesn't require the line to be cut. The line
can even run through it.
Steve.
> Thank's for the ideas and comments!
>
> >Dennis:
> >Break the line, and attach both broken ends to the arms of a V-shaped
> >metal spring, the the base of the V attached to the cylinder. Mount
> >a small magnet on one arm of the V and an Allegro linear Hall effect
> >sensor on the other arm.
>
> >FalconW:
> >Fishing line has approximately a 2 to 1 stretch ratio, so if you were
> >to mount a small magnet on the line, and a hall-effect sensor at the
> >end, you could read the stretch in the line
>
> I like the magnet idea. It would be neat to simply attach the magnet
> to a stretchy piece of line and monitor its motion in relation to a
> detector fixed in the cylinder. The magnet might run in a guide tube
> alongside the main cylinder. It doesn't require too much accuracy.
>
> >Tim M:
> >How about a strain gauge through an ADC to your data logger?
>
> >Tim McD:
> >How about a load cell that's read by the data logger?
>
> I am not sure what kind of strain gage to use or what to fasten it to.
> Does anybody know of a "strain gage" like a little piece of string
> with two loops at the ends? I'm afraid there may not be room inside
> this cylinder for the necessary amplifier. It barely holds the
> existing circuits and a coin cell.
>
> >Reg:
> >Maybe one of the Force Sensing Resistor devices? I think there are
> >issues with hysteresis and you'd probably have to temperature
> >compensate it, but it could be small & simple.
>
> That is actually what we used in a desktop prototype, but they
> operate in compression so it would need some lever action or an FSR in
> the shape of a small donut that we could bring a bolt up through to
> change tension to compression. But I can't find much variety in off
> the shelf FSRs. Is there some other material we could use like that?
>
> >Larry:
> >Maybe something like a syringe with a pressure transducer on the end
> >pull the string and the syringe pulls a vacuum you would need a
> >spring in the syringe.
>
>
> hmmm. Maybe something like a gel-filled bellows.
>
> >Michael:
> >Is it essential to put the electronics underwater? Would a system
> >aboard the boat be workable?
>
>
> I think it does have to be underwater. It will monitor a couple of
> other parameters at depth.
>
>
> -- Thanks for the great ideas, and I'm still fishing!
> Tracy
>
>
>
>
>
>
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
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> and Body of the message will be ignored.
>
>
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> http://docs.yahoo.com/info/terms/
>
>
======================================================
Steve Baldwin Electronic Product Design
TLA Microsystems Ltd Microcontroller Specialists
PO Box 15-680, New Lynn http://www.tla.co.nz
Auckland, New Zealand ph +64 9 820-2221
email: steveb@t... fax +64 9 820-1929
======================================================
stretchy tube, with a permanent magnet glued to the wall of the tube,
and a linear Hall sensor to detect small changes in paramagnetism as the
bore of the tube decreases. This could be made very small.
Dennis
Bob Nienhuis:
Re: Strain gauge. I have seen a conductive fluid filled length of rubber
or other stretchy tubing used as a strain gauge. Resistance changes as
the tube stretches and diameter changes.
Tracy:
>I like the magnet idea. It would be neat to simply attach the magnet
>to a stretchy piece of line and monitor its motion in relation to a
>detector fixed in the cylinder. The magnet might run in a guide tube
>alongside the main cylinder. It doesn't require too much accuracy.
issue, but I LOVE this idea. I think that it is incredibily creative and
novel.
Chris
<<>>
Date: Thu, 10 Jan 2002 18:01:08 -0800
From: "Larry Gaminde" <lgaminde@t...>
Subject: Re: tension in fish line
Maybe something like a syringe with a pressure transducer on the end pull
the string and the syringe pulls a vacuum you would need a spring in the
syringe.
Original Message
From: "Tracy Allen" <tracy@e...>
To: <basicstamps@yahoogroups.com>
Sent: January 10, 2002 9:17 AM
Subject: [noparse][[/noparse]basicstamps] tension in fish line
| I have a project where I need to monitor tension in a fish line, and
| the sensor has to fit in a small cylinder attached underwater in the
| line. Any ideas? I want to keep the mechanical complexity to a
| minimum. The cylinder will also contain a small PIC12C data logger
| to record the tension profile.
|
| It occurs that something like this might be useful to monitor the
| speed of a boat, by recording the drag tension.
|
| -- Tracy
________________________________________________________________
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the syringe but I have found a bimba single action pneumatic cylinder about
1.5" wide with a 3/4 stroke and a 12 pound spring for retract for $4.95,
with threaded end that could be installed into the electronic cylinder
having only the plunger end exposed. Sure would like to know if this would
work would the measurements be repeatable ??
Original Message
From: "Christopher C Dundorf" <cdundorf@j...>
To: <basicstamps@yahoogroups.com>
Sent: January 11, 2002 2:15 PM
Subject: [noparse][[/noparse]basicstamps] Re: tension in fish line
| I think that the internal friction of the syringe would probably be an
| issue, but I LOVE this idea. I think that it is incredibily creative and
| novel.
|
| Chris
|
| <<>>
|
| Date: Thu, 10 Jan 2002 18:01:08 -0800
| From: "Larry Gaminde" <lgaminde@t...>
| Subject: Re: tension in fish line
|
| Maybe something like a syringe with a pressure transducer on the end pull
| the string and the syringe pulls a vacuum you would need a spring in the
| syringe.
|
|
Original Message
| From: "Tracy Allen" <tracy@e...>
| To: <basicstamps@yahoogroups.com>
| Sent: January 10, 2002 9:17 AM
| Subject: [noparse][[/noparse]basicstamps] tension in fish line
|
|
| | I have a project where I need to monitor tension in a fish line, and
| | the sensor has to fit in a small cylinder attached underwater in the
| | line. Any ideas? I want to keep the mechanical complexity to a
| | minimum. The cylinder will also contain a small PIC12C data logger
| | to record the tension profile.
| |
| | It occurs that something like this might be useful to monitor the
| | speed of a boat, by recording the drag tension.
| |
| | -- Tracy
| ________________________________________________________________
| GET INTERNET ACCESS FROM JUNO!
| Juno offers FREE or PREMIUM Internet access for less!
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|
Have you looked into Omega's Thin Beam Load Cells? They are small in
size -- 1.25" x 0.312" x 0.063 (largest size). Smallest size is 1.20" x
0.25" x 0.006. Maybe that's still too large, though...
Ranges are from 0.25 to 40 lbs. They have some diagrams showing typical
mounting arrangements. Not sure if you could get the mechanics right to
measure tension or not. Especially since "all thin beam load cells
require mounting clamps to create a 'double bend' during loading." This
would probably increase the size requirements as well.
Good luck!
Aaron
On Thu, 10 Jan 2002 21:49:38 -0800 Tracy Allen <tracy@e...>
writes:
> >Tim M:
> >How about a strain gauge through an ADC to your data logger?
>
> >Tim McD:
> >How about a load cell that's read by the data logger?
>
> I am not sure what kind of strain gage to use or what to fasten it
> to. Does anybody know of a "strain gage" like a little piece of
> string with two loops at the ends? I'm afraid there may not be room
> inside this cylinder for the necessary amplifier. It barely holds
> the existing circuits and a coin cell.
as a pitot tube. Glue a small solid state pressure transducer inside
the tube, sealed to a hole in the tube side. As flow past the tube
opening increases, pressure decreases proportionately. You might also
add another pressure transducer which measures the 'stagnant'
(non-flowing) water inside the tube . By using the output of both
transducers as inputs to a differential amp, the difference will be
proportional to flow, independent of pressure due to depth of the
cylinder.
Dennis O'Leary
From: "Tracy Allen" <tracy@e...>
| I have a project where I need to monitor tension in a fish line, and
| the sensor has to fit in a small cylinder attached underwater in the
| line. Any ideas? I want to keep the mechanical complexity to a
| minimum. The cylinder will also contain a small PIC12C data logger to
| record the tension profile.
|
| It occurs that something like this might be useful to monitor the
| speed of a boat, by recording the drag tension.
what makes the speedometer in a boat move????
maybe just make a smaller version of this .
regards
victor Faria
Original Message
From: "Dennis P. O'Leary" <doleary@h...>
To: <basicstamps@yahoogroups.com>
Sent: Saturday, January 12, 2002 6:18 PM
Subject: RE: [noparse][[/noparse]basicstamps] Re: tension in fish line
> For a system with no mechanical parts, consider using the small cylinder
> as a pitot tube. Glue a small solid state pressure transducer inside
> the tube, sealed to a hole in the tube side. As flow past the tube
> opening increases, pressure decreases proportionately. You might also
> add another pressure transducer which measures the 'stagnant'
> (non-flowing) water inside the tube . By using the output of both
> transducers as inputs to a differential amp, the difference will be
> proportional to flow, independent of pressure due to depth of the
> cylinder.
>
> Dennis O'Leary
>
>
> From: "Tracy Allen" <tracy@e...>
> | I have a project where I need to monitor tension in a fish line, and
> | the sensor has to fit in a small cylinder attached underwater in the
> | line. Any ideas? I want to keep the mechanical complexity to a
> | minimum. The cylinder will also contain a small PIC12C data logger to
>
> | record the tension profile.
> |
> | It occurs that something like this might be useful to monitor the
> | speed of a boat, by recording the drag tension.
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
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Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
restored a few years ago. It basically measures air pressure.
A boat speedometer has a small fin that is in the water under the boat. The
fin has a small hole in the front that is attached to a hollow rubber tube that
goes to a cylinder and then a hollow rubber tube that goes to the speedometer.
Water goes in the fin hole when the boat accelerates, the water gets pushed up
a tube into the cylinder, the air that was in the cylinder gets compressed and
pushed through a tube to the speedometer, and the speedometer has a spring
loaded cylinder / plunger that gets moved by the air pressure and turns the
needle.
I don't think that this would work for your application, but it might give you
some other ideas. How about a simple mechanical approach. Hard mount a pully
on on a spring loaded trim pot for the string to wrap around, and wire the trim
pot as a voltage divider and measure the voltage. You could also spring load a
slider in the same way, and mount it in some sort of tube.
stew
On Sat, 12 Jan 2002 18:33:39 -0500, victor Faria wrote:
>I wonder if you could use existing technology???
>what makes the speedometer in a boat move????
>maybe just make a smaller version of this .
>regards
>victor Faria
>
Original Message
>From: "Dennis P. O'Leary" <doleary@h...>
>To: <basicstamps@yahoogroups.com>
>Sent: Saturday, January 12, 2002 6:18 PM
>Subject: RE: [noparse][[/noparse]basicstamps] Re: tension in fish line
in one of the catalogs(jameco)I think I saw a flex resistor
it was a straight bar of some sort and as it flexes the resistance changes.
so think of a fishing pole as it bends so would the resistor.it was
attached then just read a current going through the resister like the pot
command.
regards
victor
Original Message
From: "Stewart Mayer" <stewlist@k...>
To: <basicstamps@yahoogroups.com>
Sent: Sunday, January 13, 2002 5:17 PM
Subject: Re: [noparse][[/noparse]basicstamps] Re: tension in fish line
> I installed a boat speedometer on a "classic" fleetcraft outboard that I
> restored a few years ago. It basically measures air pressure.
>
> A boat speedometer has a small fin that is in the water under the boat.
The
> fin has a small hole in the front that is attached to a hollow rubber tube
that
> goes to a cylinder and then a hollow rubber tube that goes to the
speedometer.
> Water goes in the fin hole when the boat accelerates, the water gets
pushed up
> a tube into the cylinder, the air that was in the cylinder gets compressed
and
> pushed through a tube to the speedometer, and the speedometer has a spring
> loaded cylinder / plunger that gets moved by the air pressure and turns
the
> needle.
>
> I don't think that this would work for your application, but it might give
you
> some other ideas. How about a simple mechanical approach. Hard mount a
pully
> on on a spring loaded trim pot for the string to wrap around, and wire the
trim
> pot as a voltage divider and measure the voltage. You could also spring
load a
> slider in the same way, and mount it in some sort of tube.
>
> stew
>
> On Sat, 12 Jan 2002 18:33:39 -0500, victor Faria wrote:
> >I wonder if you could use existing technology???
> >what makes the speedometer in a boat move????
> >maybe just make a smaller version of this .
> >regards
> >victor Faria
> >
Original Message
> >From: "Dennis P. O'Leary" <doleary@h...>
> >To: <basicstamps@yahoogroups.com>
> >Sent: Saturday, January 12, 2002 6:18 PM
> >Subject: RE: [noparse][[/noparse]basicstamps] Re: tension in fish line
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
I can even tell you how to make it read through the hull without drilling
holes.
Original Message
> I installed a boat speedometer on a "classic" fleetcraft outboard that I
> restored a few years ago. It basically measures air pressure.
>
> A boat speedometer has a small fin that is in the water under the boat.
The
> fin has a small hole in the front that is attached to a hollow rubber tube
that
> goes to a cylinder and then a hollow rubber tube that goes to the
speedometer.
> Water goes in the fin hole when the boat accelerates, the water gets
pushed up
> a tube into the cylinder, the air that was in the cylinder gets compressed
and
> pushed through a tube to the speedometer, and the speedometer has a spring
> loaded cylinder / plunger that gets moved by the air pressure and turns
the
> needle.
>
> I don't think that this would work for your application, but it might give
you
> some other ideas. How about a simple mechanical approach. Hard mount a
pully
> on on a spring loaded trim pot for the string to wrap around, and wire the
trim
> pot as a voltage divider and measure the voltage. You could also spring
load a
> slider in the same way, and mount it in some sort of tube.
> >I wonder if you could use existing technology???
> >what makes the speedometer in a boat move????
> >maybe just make a smaller version of this .
thought experiments - and I have a similar idea to Victor.
Imagine the fishing line passing thru the cylinder. Connect a small spring
from the middle of the line inside the cylinder to the edge of the cylinder.
The spring tensions the line so that the line makes a slight Y shape. Glue a
flexi strain guage across the top of the Y. Hey presto, the guage will flex
depending on the tug on the line. If the line stretches too much for the
load, use steel piano or guitar wire inside the cylinder. Easily
waterproofed too. Put two clips on the line just outside the cyclinder to
keep the line inside slightly tensioned and stop the insides moving about
when there is no load.
Regards,
Tony Wells
Original Message
From: "victor Faria" <victorf@g...>
To: <basicstamps@yahoogroups.com>
Sent: Sunday, January 13, 2002 10:21 PM
Subject: Re: [noparse][[/noparse]basicstamps] Re: tension in fish line
> Here is another thought!
> in one of the catalogs(jameco)I think I saw a flex resistor
> it was a straight bar of some sort and as it flexes the resistance
changes.
> so think of a fishing pole as it bends so would the resistor.it was
> attached then just read a current going through the resister like the pot
> command.
> regards
> victor
>
>
Original Message
> From: "Stewart Mayer" <stewlist@k...>
> To: <basicstamps@yahoogroups.com>
> Sent: Sunday, January 13, 2002 5:17 PM
> Subject: Re: [noparse][[/noparse]basicstamps] Re: tension in fish line
>
>
> > I installed a boat speedometer on a "classic" fleetcraft outboard that I
> > restored a few years ago. It basically measures air pressure.
> >
> > A boat speedometer has a small fin that is in the water under the boat.
> The
> > fin has a small hole in the front that is attached to a hollow rubber
tube
> that
> > goes to a cylinder and then a hollow rubber tube that goes to the
> speedometer.
> > Water goes in the fin hole when the boat accelerates, the water gets
> pushed up
> > a tube into the cylinder, the air that was in the cylinder gets
compressed
> and
> > pushed through a tube to the speedometer, and the speedometer has a
spring
> > loaded cylinder / plunger that gets moved by the air pressure and turns
> the
> > needle.
> >
> > I don't think that this would work for your application, but it might
give
> you
> > some other ideas. How about a simple mechanical approach. Hard mount a
> pully
> > on on a spring loaded trim pot for the string to wrap around, and wire
the
> trim
> > pot as a voltage divider and measure the voltage. You could also spring
> load a
> > slider in the same way, and mount it in some sort of tube.
> >
> > stew
> >
> > On Sat, 12 Jan 2002 18:33:39 -0500, victor Faria wrote:
> > >I wonder if you could use existing technology???
> > >what makes the speedometer in a boat move????
> > >maybe just make a smaller version of this .
> > >regards
> > >victor Faria
> > >
Original Message
> > >From: "Dennis P. O'Leary" <doleary@h...>
> > >To: <basicstamps@yahoogroups.com>
> > >Sent: Saturday, January 12, 2002 6:18 PM
> > >Subject: RE: [noparse][[/noparse]basicstamps] Re: tension in fish line
> >
> >
> >
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read speed (my brother is a major fisherman with all the toys), but the old
style speedometer was a nice touch to keep the "vintage" boat looking
"vintage". Although it may sound like blasphemy, I'm trying to keep this
beauty "mico-controller free" [noparse]:)[/noparse] Sometimes good ideas come from old solutions
too, even if they are mechanical. Sorry if i'm getting off topic.
stew
On Sun, 13 Jan 2002 16:39:52 -0600, Rodent wrote:
>Typically all but the cheapest fish-finders will also have a speed function.
>I can even tell you how to make it read through the hull without drilling
>holes.
>
--
Stewart Mayer, stewlist@k... on 01/13/2002
actually servo-driven -- that would solve the instrument problem. As far as
the sensor, I would suspect anything but pressure and a propeller would be
non-linear and would require some brainwork to process with an analog
circuit.
Original Message
> Yeah, i've seen a few fish finders with thru-hull transducers that can
also
> read speed (my brother is a major fisherman with all the toys), but the
old
> style speedometer was a nice touch to keep the "vintage" boat looking
> "vintage". Although it may sound like blasphemy, I'm trying to keep this
> beauty "mico-controller free" [noparse]:)[/noparse] Sometimes good ideas come from old
solutions
> too, even if they are mechanical. Sorry if i'm getting off topic.
> >Typically all but the cheapest fish-finders will also have a speed
function.
> >I can even tell you how to make it read through the hull without drilling
> >holes.