Counting pulses from a bicycle speed sensor
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Posts: 46,084
I'm new to the group; please forgive if this has been answered, but I
couldn't find it in the archives.
I want to count pulses that come from a bicycle speed sensor. The
speed sensor system is a little magnet that attaches to the spokes,
which produces an electrical pulse each time the magnet crosses the
sensor, which is typically mounted on the frame near the wheel.
I borrowed an oscope from a friend and measured some sample pulses.
The oscope leads are very poor, so I couldn't measure the peak voltage
(I'm working on this), but I did measure the pulse width to be about
3-20 msec. depending on the speed of the back wheel. The pulses come
at a rate of about 1-10 Hz. A simple physics calculation for the
pulsewidth gives results similar to the measurement.
It seems to me that using the COUNT function will work well for this
application. *However*, I don't think that the peak voltage of the
pulses from the sensor will trip the BS2 threshold (1.4 V, if I
remember correctly).
So, I'm considering building a simple audio amplifier to condition the
pulses and bring them up to TTL levels.
My question: has anybody used a BS to measure pulses from a bicycle
speed sensor and if so, how did you do it? If not, can anybody provide
a critique of my proposed method?
(I just order the BOE kit, and haven't tried doing this yet ...)
Thanks,
Michael
couldn't find it in the archives.
I want to count pulses that come from a bicycle speed sensor. The
speed sensor system is a little magnet that attaches to the spokes,
which produces an electrical pulse each time the magnet crosses the
sensor, which is typically mounted on the frame near the wheel.
I borrowed an oscope from a friend and measured some sample pulses.
The oscope leads are very poor, so I couldn't measure the peak voltage
(I'm working on this), but I did measure the pulse width to be about
3-20 msec. depending on the speed of the back wheel. The pulses come
at a rate of about 1-10 Hz. A simple physics calculation for the
pulsewidth gives results similar to the measurement.
It seems to me that using the COUNT function will work well for this
application. *However*, I don't think that the peak voltage of the
pulses from the sensor will trip the BS2 threshold (1.4 V, if I
remember correctly).
So, I'm considering building a simple audio amplifier to condition the
pulses and bring them up to TTL levels.
My question: has anybody used a BS to measure pulses from a bicycle
speed sensor and if so, how did you do it? If not, can anybody provide
a critique of my proposed method?
(I just order the BOE kit, and haven't tried doing this yet ...)
Thanks,
Michael
Comments
webbm@c... writes:
I'm new to the group; please forgive if this has been answered, but I
couldn't find it in the archives.
I want to count pulses that come from a bicycle speed sensor. The
speed sensor system is a little magnet that attaches to the spokes,
which produces an electrical pulse each time the magnet crosses the
sensor, which is typically mounted on the frame near the wheel.
I borrowed an oscope from a friend and measured some sample pulses.
The oscope leads are very poor, so I couldn't measure the peak voltage
(I'm working on this), but I did measure the pulse width to be about
3-20 msec. depending on the speed of the back wheel. The pulses come
at a rate of about 1-10 Hz. A simple physics calculation for the
pulsewidth gives results similar to the measurement.
It seems to me that using the COUNT function will work well for this
application. *However*, I don't think that the peak voltage of the
pulses from the sensor will trip the BS2 threshold (1.4 V, if I
remember correctly).
So, I'm considering building a simple audio amplifier to condition the
pulses and bring them up to TTL levels.
My question: has anybody used a BS to measure pulses from a bicycle
speed sensor and if so, how did you do it? If not, can anybody provide
a critique of my proposed method?
(I just order the BOE kit, and haven't tried doing this yet ...)
Thanks,
Michael
+++++++++++++++++++++++++++++++++++++++++++++++++++
Michael,
Most bicycle wheel speed sensors I have seen are simply a reed switch that is
closed by the wheel mounted magnet, and the bike computer provided the
threshold voltage.
To confirm this for your set up do the following:
Simply take an ohm meter and connect it across the two leads comingfrom the
wheel speed sensor (and nothing else connected to the sensor.....ie, disconnect
the computer from its mount and connect the meter on the two metal tabs of
the mount). It should read open.
Then take a magnet and hold it next to the wheel speed sensor and confirm the
ohm meter now reads a closed circiut.
If this is the case, you are home free.
Simple connect one lead of the wheel speed sensor to ground. Connect the
other wire to two places, one to the stamp input pin, and to a 10k resistor.
Connect the other end of the 10k resistor to the stamp +5 volt regulator output.
Now as you pass the magnet past the sensor watch the stamp input pin, you
should read 0volts and 5 volts.
Now why would you go through the trouble of building this bike computer when
you can get one frr $20?????? easy, because it is fun to build stuff like
this......
Email back with further questions.
ken
[noparse][[/noparse]Non-text portions of this message have been removed]
10 years of college and graduate school in Physics, 5 years working in
a laser lab, and I've never heard of a "reed switch". Thanks! I had
assumed that the magnet on the spokes was inducing a voltage pulse in
a coil, which the computer detected. Of course, now that I think about
what you've said, it makes much more sense to simply close a switch.
I checked, and my computer works exactly as you stated. This
simplifies my problem greatly. Who says the internet isn't good for
anything?
Background: my motiviation for this is to build a science fair
experiment for my daughter. We are going to instrument her hamster's
exercise wheel so we can measure how often (how fast, etc.) he runs on
the wheel. He exercises mostly at night, so we want to be able to do
this remotely while we sleep, hence the BASIC Stamp. After we
establish a baseline, we'll check things like how light (and
temperature? music?) affect his exercise habits.
Of course, after that, I'm going to use the stamp to record my indoor
bike workouts on the trainer ...
Cheers, and thanks again,
Michael
> Michael,
>
> Most bicycle wheel speed sensors I have seen are simply a reed
switch that is
> closed by the wheel mounted magnet, and the bike computer provided the
> threshold voltage.
>
> To confirm this for your set up do the following:
>
> Simply take an ohm meter and connect it across the two leads
comingfrom the
> wheel speed sensor (and nothing else connected to the sensor.....ie,
disconnect
> the computer from its mount and connect the meter on the two metal
tabs of
> the mount). It should read open.
> Then take a magnet and hold it next to the wheel speed sensor and
confirm the
> ohm meter now reads a closed circiut.
>
> If this is the case, you are home free.
>
> Simple connect one lead of the wheel speed sensor to ground. Connect
the
> other wire to two places, one to the stamp input pin, and to a 10k
resistor.
> Connect the other end of the 10k resistor to the stamp +5 volt
regulator output.
>
> Now as you pass the magnet past the sensor watch the stamp input
pin, you
> should read 0volts and 5 volts.
>
> Now why would you go through the trouble of building this bike
computer when
> you can get one frr $20?????? easy, because it is fun to build
stuff like
> this......
>
> Email back with further questions.
>
> ken
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
using small rare-earth magnets [noparse][[/noparse]you can get them at Radio Shack] and a
Hall-effect sensor that you can connect right to the Stamp.
-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office
Original Message
From: webbm03 [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=JVy-M66BBnP51-SYc8K_XWXZAOZFTJ74qEALamI9lQfxkP5dfX2liz43thWYfxf9yK6PSg12DA]webbm@c...[/url
Sent: Saturday, October 04, 2003 7:56 AM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Re: Counting pulses from a bicycle speed sensor
Ken,
10 years of college and graduate school in Physics, 5 years working in a
laser lab, and I've never heard of a "reed switch". Thanks! I had
assumed that the magnet on the spokes was inducing a voltage pulse in a
coil, which the computer detected. Of course, now that I think about
what you've said, it makes much more sense to simply close a switch.
I checked, and my computer works exactly as you stated. This simplifies
my problem greatly. Who says the internet isn't good for anything?
Background: my motiviation for this is to build a science fair
experiment for my daughter. We are going to instrument her hamster's
exercise wheel so we can measure how often (how fast, etc.) he runs on
the wheel. He exercises mostly at night, so we want to be able to do
this remotely while we sleep, hence the BASIC Stamp. After we establish
a baseline, we'll check things like how light (and temperature? music?)
affect his exercise habits.
Of course, after that, I'm going to use the stamp to record my indoor
bike workouts on the trainer ...
Cheers, and thanks again,
Michael
> Michael,
>
> Most bicycle wheel speed sensors I have seen are simply a reed
switch that is
> closed by the wheel mounted magnet, and the bike computer provided the
> threshold voltage.
>
> To confirm this for your set up do the following:
>
> Simply take an ohm meter and connect it across the two leads
comingfrom the
> wheel speed sensor (and nothing else connected to the sensor.....ie,
disconnect
> the computer from its mount and connect the meter on the two metal
tabs of
> the mount). It should read open.
> Then take a magnet and hold it next to the wheel speed sensor and
confirm the
> ohm meter now reads a closed circiut.
>
> If this is the case, you are home free.
>
> Simple connect one lead of the wheel speed sensor to ground. Connect
the
> other wire to two places, one to the stamp input pin, and to a 10k
resistor.
> Connect the other end of the 10k resistor to the stamp +5 volt
regulator output.
>
> Now as you pass the magnet past the sensor watch the stamp input
pin, you
> should read 0volts and 5 volts.
>
> Now why would you go through the trouble of building this bike
computer when
> you can get one frr $20?????? easy, because it is fun to build
stuff like
> this......
>
> Email back with further questions.
>
> ken
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
To UNSUBSCRIBE, just send mail to:
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should compute the number of hamsters (and corresponding level of hampster
chow) that are required for meeting the projected US energy demand. Of
course, I'm a firm believer in hampster power.
On Sat, 4 Oct 2003, Jon Williams wrote:
> Since you're going to be outfitting a hamster wheel, you might consider
> using small rare-earth magnets [noparse][[/noparse]you can get them at Radio Shack] and a
> Hall-effect sensor that you can connect right to the Stamp.
>
> -- Jon Williams
> -- Applications Engineer, Parallax
> -- Dallas Office
>
>
>
Original Message
> From: webbm03 [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=zU4AXBttcHXy121bGqWQUZmgZWCK_7YbWBlM0IzC2j7fm3qdo8OWcE2UtdQFdhY5bEG6ppxEPg_ELK_j]webbm@c...[/url
> Sent: Saturday, October 04, 2003 7:56 AM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] Re: Counting pulses from a bicycle speed sensor
>
>
> Ken,
>
> 10 years of college and graduate school in Physics, 5 years working in a
> laser lab, and I've never heard of a "reed switch". Thanks! I had
> assumed that the magnet on the spokes was inducing a voltage pulse in a
> coil, which the computer detected. Of course, now that I think about
> what you've said, it makes much more sense to simply close a switch.
>
> I checked, and my computer works exactly as you stated. This simplifies
> my problem greatly. Who says the internet isn't good for anything?
>
> Background: my motiviation for this is to build a science fair
> experiment for my daughter. We are going to instrument her hamster's
> exercise wheel so we can measure how often (how fast, etc.) he runs on
> the wheel. He exercises mostly at night, so we want to be able to do
> this remotely while we sleep, hence the BASIC Stamp. After we establish
> a baseline, we'll check things like how light (and temperature? music?)
> affect his exercise habits.
>
> Of course, after that, I'm going to use the stamp to record my indoor
> bike workouts on the trainer ...
>
> Cheers, and thanks again,
>
> Michael
>
>
> > Michael,
> >
> > Most bicycle wheel speed sensors I have seen are simply a reed
> switch that is
> > closed by the wheel mounted magnet, and the bike computer provided the
> > threshold voltage.
> >
> > To confirm this for your set up do the following:
> >
> > Simply take an ohm meter and connect it across the two leads
> comingfrom the
> > wheel speed sensor (and nothing else connected to the sensor.....ie,
> disconnect
> > the computer from its mount and connect the meter on the two metal
> tabs of
> > the mount). It should read open.
> > Then take a magnet and hold it next to the wheel speed sensor and
> confirm the
> > ohm meter now reads a closed circiut.
> >
> > If this is the case, you are home free.
> >
> > Simple connect one lead of the wheel speed sensor to ground. Connect
> the
> > other wire to two places, one to the stamp input pin, and to a 10k
> resistor.
> > Connect the other end of the 10k resistor to the stamp +5 volt
> regulator output.
> >
> > Now as you pass the magnet past the sensor watch the stamp input
> pin, you
> > should read 0volts and 5 volts.
> >
> > Now why would you go through the trouble of building this bike
> computer when
> > you can get one frr $20?????? easy, because it is fun to build
> stuff like
> > this......
> >
> > Email back with further questions.
> >
> > ken
> >
> >
> > [noparse][[/noparse]Non-text portions of this message have been removed]
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
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> and Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
>
>
>
> This message has been scanned by WebShield. Please report SPAM to
> abuse@p....
>
>
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>
>
>
Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
email: lamont@a... WWW: http://www.serv.net
"Do not fear mistakes, There Are None" - Miles Davis
the hamster as he runs at various speeds. The physicist in me just
can't resist.
I plan to do some simple measurements of "spin-down" times beginning
with various wheel speeds, and estimate the speed-dependent (I assume)
friction in the wheel. Of course, this will be only the work that
hamster's doing on the wheel, which doesn't include the work he's
doing within his body to run. Nevertheless, it will give us an
estimate of how much "external" work he can do.
Does anybody out there know of another way to measure power on such a
small scale? Measuring "spin-down" times may be somewhat inaccurate ...
So, "if you have an infinite number of hamsters running on an infinite
number of wheels, how many fewer dinosaurs will you burn in 100 years ..."
Michael
--- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
<lamont@a...> wrote:
>
>
> As an interesting correlary to this science fair project, I think you
> should compute the number of hamsters (and corresponding level of
hampster
> chow) that are required for meeting the projected US energy demand. Of
> course, I'm a firm believer in hampster power.
>
As a check on the force measured by spin-down time, one can also
calculate the energy in the wheel (in steady state) as:
KE = 1/2 I w^2,
where I = rotational inertia and w = angular speed. This should equal
the work being done (against friction) by the hamster when he's in
steady state. It's a relatively easy manner to calculate I for a
hamster wheel (consider it a disk glued to a ring annulus):
I = MR^2 [noparse][[/noparse] R^2/[noparse][[/noparse]2*(2Rd+R^2)] + 2Rd/(2Rd+R^2) ]
where R is the radius of the wheel, M is the wheel's mass, and d is
the "width" or "depth" of the wheel. This ignores the axle, and
assumes uniform thickness or density of material.
It will be interesting to see how this compares to the work
calculation gotten by measuring spin-down time, and it would be great
to compare this to a true measurement of work with some small
"ergometer". Anybody have any ideas on how to measure power in this
small system?
Michael
--- In basicstamps@yahoogroups.com, "webbm03" <webbm@c...> wrote:
> As an aside to the project, I intend to estimate the power output of
> the hamster as he runs at various speeds. The physicist in me just
> can't resist.
>
> I plan to do some simple measurements of "spin-down" times beginning
> with various wheel speeds, and estimate the speed-dependent (I assume)
> friction in the wheel. Of course, this will be only the work that
> hamster's doing on the wheel, which doesn't include the work he's
> doing within his body to run. Nevertheless, it will give us an
> estimate of how much "external" work he can do.
>
> Does anybody out there know of another way to measure power on such a
> small scale? Measuring "spin-down" times may be somewhat inaccurate ...
>
> So, "if you have an infinite number of hamsters running on an infinite
> number of wheels, how many fewer dinosaurs will you burn in 100
years ..."
>
> Michael
You could try to mount a small DC motor on the wheel, it will then act as a
dynamo.
By putting different resistors on the DC motor you can vary the load it puts
on the wheel and you can estimate de generated power.
You also can put electric power on the motor and see how fast the hamster
can run at top speed :-).
Klaus
Oorspronkelijk bericht
Van: webbm03 [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=2J7KhYkHyIF3GDJt-Mtol2UcYIk5EH1vBmF3dVrX8V09QTlw-I6zdBPzAov5DEqwBtikUtyDLSU]webbm@c...[/url
Verzonden: dinsdag 7 oktober 2003 14:29
Aan: basicstamps@yahoogroups.com
Onderwerp: [noparse][[/noparse]basicstamps] Re: Counting pulses from a bicycle speed sensor
As an aside to the project, I intend to estimate the power output of
the hamster as he runs at various speeds. The physicist in me just
can't resist.
I plan to do some simple measurements of "spin-down" times beginning
with various wheel speeds, and estimate the speed-dependent (I assume)
friction in the wheel. Of course, this will be only the work that
hamster's doing on the wheel, which doesn't include the work he's
doing within his body to run. Nevertheless, it will give us an
estimate of how much "external" work he can do.
Does anybody out there know of another way to measure power on such a
small scale? Measuring "spin-down" times may be somewhat inaccurate ...
So, "if you have an infinite number of hamsters running on an infinite
number of wheels, how many fewer dinosaurs will you burn in 100 years ..."
Michael
--- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
<lamont@a...> wrote:
>
>
> As an interesting correlary to this science fair project, I think you
> should compute the number of hamsters (and corresponding level of
hampster
> chow) that are required for meeting the projected US energy demand. Of
> course, I'm a firm believer in hampster power.
>
To UNSUBSCRIBE, just send mail to:
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Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
the best. I've seen hamsters use their wheels,
and usually they run in 'spurts'. So they
speed up the wheel, then they slow down the
wheel to a stop, then speed up the wheel again, etc.
Putting a small electric motor on the wheel will
integrate all this activity into some useful
output you can measure. Otherwise, you'll have
to know the weight of the hamster, when he is
accelerating, when he is descellerating, etc.
You'll still need to measure wheel velocity,
I think.
You'll want to keep the increase in resistance
to the hamster low, of course, or he won't use
the wheel -- so don't put too big a resistor
on that motor.
--- In basicstamps@yahoogroups.com, "NLnet" <Klaus.Jong@n...> wrote:
> Michael,
>
> You could try to mount a small DC motor on the wheel, it will then
act as a
> dynamo.
>
> By putting different resistors on the DC motor you can vary the
load it puts
> on the wheel and you can estimate de generated power.
>
> You also can put electric power on the motor and see how fast the
hamster
> can run at top speed :-).
>
> Klaus
>
>
Oorspronkelijk bericht
> Van: webbm03 [noparse][[/noparse]mailto:webbm@c...]
> Verzonden: dinsdag 7 oktober 2003 14:29
> Aan: basicstamps@yahoogroups.com
> Onderwerp: [noparse][[/noparse]basicstamps] Re: Counting pulses from a bicycle speed
sensor
>
>
> As an aside to the project, I intend to estimate the power output of
> the hamster as he runs at various speeds. The physicist in me just
> can't resist.
>
> I plan to do some simple measurements of "spin-down" times beginning
> with various wheel speeds, and estimate the speed-dependent (I
assume)
> friction in the wheel. Of course, this will be only the work that
> hamster's doing on the wheel, which doesn't include the work he's
> doing within his body to run. Nevertheless, it will give us an
> estimate of how much "external" work he can do.
>
> Does anybody out there know of another way to measure power on such
a
> small scale? Measuring "spin-down" times may be somewhat
inaccurate ...
>
> So, "if you have an infinite number of hamsters running on an
infinite
> number of wheels, how many fewer dinosaurs will you burn in 100
years ..."
>
> Michael
>
>
> --- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
> <lamont@a...> wrote:
> >
> >
> > As an interesting correlary to this science fair project, I think
you
> > should compute the number of hamsters (and corresponding level of
> hampster
> > chow) that are required for meeting the projected US energy
demand. Of
> > course, I'm a firm believer in hampster power.
> >
>
>
> 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/
might get the hamster to generate enough power to charge a battery to run
the Stamp itself, which it could then integrate into a "hamster power"
profile. Sort of like a hamster breeder-reactor, as it were. Any extra power
could be diverted to run an LED or other cool display. Could this be used to
entice the hamster to even higher energy outputs? Or perhaps it could be
used to stimulate the hamster's pleasure center directly? I'm really kidding
about putting tiny electrodes in their little brains, but maybe that sort of
thing would work on humans to keep them on their exercise bikes. Sort of
like a spinning class from hell....
Mike Sokol
www.modernrecording.com
mikes@m...
" One should not increase, beyond what is necessary,
the number of entities required to explain anything"...
-William of Occam-
Original Message
From: "Allan Lane" <allan.lane@h...>
To: <basicstamps@yahoogroups.com>
Sent: Tuesday, October 07, 2003 5:49 PM
Subject: [noparse][[/noparse]basicstamps] Re: Counting pulses from a bicycle speed sensor
> Of all the suggestions so far, I like this one
> the best. I've seen hamsters use their wheels,
> and usually they run in 'spurts'. So they
> speed up the wheel, then they slow down the
> wheel to a stop, then speed up the wheel again, etc.
>
> Putting a small electric motor on the wheel will
> integrate all this activity into some useful
> output you can measure. Otherwise, you'll have
> to know the weight of the hamster, when he is
> accelerating, when he is descellerating, etc.
> You'll still need to measure wheel velocity,
> I think.
>
> You'll want to keep the increase in resistance
> to the hamster low, of course, or he won't use
> the wheel -- so don't put too big a resistor
> on that motor.
>
> --- In basicstamps@yahoogroups.com, "NLnet" <Klaus.Jong@n...> wrote:
> > Michael,
> >
> > You could try to mount a small DC motor on the wheel, it will then
> act as a
> > dynamo.
> >
> > By putting different resistors on the DC motor you can vary the
> load it puts
> > on the wheel and you can estimate de generated power.
> >
> > You also can put electric power on the motor and see how fast the
> hamster
> > can run at top speed :-).
> >
> > Klaus
> >
> >
Oorspronkelijk bericht
> > Van: webbm03 [noparse][[/noparse]mailto:webbm@c...]
> > Verzonden: dinsdag 7 oktober 2003 14:29
> > Aan: basicstamps@yahoogroups.com
> > Onderwerp: [noparse][[/noparse]basicstamps] Re: Counting pulses from a bicycle speed
> sensor
> >
> >
> > As an aside to the project, I intend to estimate the power output of
> > the hamster as he runs at various speeds. The physicist in me just
> > can't resist.
> >
> > I plan to do some simple measurements of "spin-down" times beginning
> > with various wheel speeds, and estimate the speed-dependent (I
> assume)
> > friction in the wheel. Of course, this will be only the work that
> > hamster's doing on the wheel, which doesn't include the work he's
> > doing within his body to run. Nevertheless, it will give us an
> > estimate of how much "external" work he can do.
> >
> > Does anybody out there know of another way to measure power on such
> a
> > small scale? Measuring "spin-down" times may be somewhat
> inaccurate ...
> >
> > So, "if you have an infinite number of hamsters running on an
> infinite
> > number of wheels, how many fewer dinosaurs will you burn in 100
> years ..."
> >
> > Michael
> >
> >
> > --- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
> > <lamont@a...> wrote:
> > >
> > >
> > > As an interesting correlary to this science fair project, I think
> you
> > > should compute the number of hamsters (and corresponding level of
> > hampster
> > > chow) that are required for meeting the projected US energy
> demand. Of
> > > course, I'm a firm believer in hampster power.
> > >
> >
> >
> > To UNSUBSCRIBE, just send mail to:
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>
of thermodynamics (layman's version):
1) You can't win.
2) You can't even break even.
3) Things are going to get worse before they get better.
4) Who says they're going to get better?
Dennis
Original Message
From: Mike Sokol - ModernRecording [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=lDGRmgQDlrrChiuGaJTI_Snzt7Ml6-clGiOriyPY_4cQiXExPtEAnXMQ_4Cm6BX7B5Q0cGU4mjTkdA6inDP6pQbUSg]mikes@m...[/url
Sent: Tuesday, October 07, 2003 4:34 PM
To: basicstamps@yahoogroups.com
Subject: Re: [noparse][[/noparse]basicstamps] Re: Counting pulses from a bicycle speed
sensor
Rather than heating up a resistor and throwing away the waste heat, you
might get the hamster to generate enough power to charge a battery to
run the Stamp itself, which it could then integrate into a "hamster
power" profile. Sort of like a hamster breeder-reactor, as it were. Any
extra power could be diverted to run an LED or other cool display. Could
this be used to entice the hamster to even higher energy outputs? Or
perhaps it could be used to stimulate the hamster's pleasure center
directly? I'm really kidding about putting tiny electrodes in their
little brains, but maybe that sort of thing would work on humans to keep
them on their exercise bikes. Sort of like a spinning class from
hell....
Mike Sokol
www.modernrecording.com
mikes@m...
" One should not increase, beyond what is necessary,
the number of entities required to explain anything"... -William of
Occam-
Original Message
From: "Allan Lane" <allan.lane@h...>
To: <basicstamps@yahoogroups.com>
Sent: Tuesday, October 07, 2003 5:49 PM
Subject: [noparse][[/noparse]basicstamps] Re: Counting pulses from a bicycle speed sensor
> Of all the suggestions so far, I like this one
> the best. I've seen hamsters use their wheels,
> and usually they run in 'spurts'. So they
> speed up the wheel, then they slow down the
> wheel to a stop, then speed up the wheel again, etc.
>
> Putting a small electric motor on the wheel will
> integrate all this activity into some useful
> output you can measure. Otherwise, you'll have
> to know the weight of the hamster, when he is
> accelerating, when he is descellerating, etc.
> You'll still need to measure wheel velocity,
> I think.
>
> You'll want to keep the increase in resistance
> to the hamster low, of course, or he won't use
> the wheel -- so don't put too big a resistor
> on that motor.
>
> --- In basicstamps@yahoogroups.com, "NLnet" <Klaus.Jong@n...> wrote:
> > Michael,
> >
> > You could try to mount a small DC motor on the wheel, it will then
> act as a
> > dynamo.
> >
> > By putting different resistors on the DC motor you can vary the
> load it puts
> > on the wheel and you can estimate de generated power.
> >
> > You also can put electric power on the motor and see how fast the
> hamster
> > can run at top speed :-).
> >
> > Klaus
> >
> >
Oorspronkelijk bericht
> > Van: webbm03 [noparse][[/noparse]mailto:webbm@c...]
> > Verzonden: dinsdag 7 oktober 2003 14:29
> > Aan: basicstamps@yahoogroups.com
> > Onderwerp: [noparse][[/noparse]basicstamps] Re: Counting pulses from a bicycle speed
> sensor
> >
> >
> > As an aside to the project, I intend to estimate the power output of
> > the hamster as he runs at various speeds. The physicist in me just
> > can't resist.
> >
> > I plan to do some simple measurements of "spin-down" times beginning
> > with various wheel speeds, and estimate the speed-dependent (I
> assume)
> > friction in the wheel. Of course, this will be only the work that
> > hamster's doing on the wheel, which doesn't include the work he's
> > doing within his body to run. Nevertheless, it will give us an
> > estimate of how much "external" work he can do.
> >
> > Does anybody out there know of another way to measure power on such
> a
> > small scale? Measuring "spin-down" times may be somewhat
> inaccurate ...
> >
> > So, "if you have an infinite number of hamsters running on an
> infinite
> > number of wheels, how many fewer dinosaurs will you burn in 100
> years ..."
> >
> > Michael
> >
> >
> > --- In basicstamps@yahoogroups.com, "Sean T. Lamont .lost."
> > <lamont@a...> wrote:
> > >
> > >
> > > As an interesting correlary to this science fair project, I think
> you
> > > should compute the number of hamsters (and corresponding level of
> > hampster
> > > chow) that are required for meeting the projected US energy
> demand. Of
> > > course, I'm a firm believer in hampster power.
> > >
> >
> >
> > 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.
> >
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