rmd74

Can someone help me figuring out wich sensor or device would be best 

to track the (rotation) speed of a fixed bicycle? The speed data is 

then suposed to control the triggering and speed of some movie clips 

with Max/MSP/Jitter in osX, using some analogue to digital converter, 

wich, by the way, I would apreciate some advices about.

I've worked with sensors before, like flex, light, pressure and 

others, but none of these would be of any use for this project.

Can someone help me figuring out wich sensor or device would be best  
to track the (rotation) speed of a fixed bicycle? The speed data is  
then suposed to control the triggering and speed of some movie clips  
with Max/MSP/Jitter in osX, using some analogue to digital converter,  
wich, by the way, I would apreciate some advices about.
I've worked with sensors before, like flex, light, pressure and  
others, but none of these would be of any use for this project.

tracking-a-bicycle-speed

I'd look into a Hall effect sensor paired with a magnet or magnets. 

You really need something hi-speed, and these should be quite accurate. 

There was a cool project at the NYU ITP department that used that to 

drive a persistence of vision LED display in the bike wheel spokes.

I'd look into a Hall effect sensor paired with a magnet or magnets.  
You really need something hi-speed, and these should be quite accurate. 
  There was a cool project at the NYU ITP department that used that to 
drive a persistence of vision LED display in the bike wheel spokes.

You could try one of those old light sets that has a small generator 

with a wheel that rubs against the tyre - as you cycle faster the 

light gets brighter - so a simple a to d would get you a value you 

could work with. (although you might have to check the voltage 

doesn't get to high and damage your a to d)

You could try one of those old light sets that has a small generator 
with a wheel that rubs against the tyre - as you cycle faster the 
light gets brighter - so a simple a to d would get you a value you 
could work with. (although you might have to check the voltage 
doesn't get to high and damage your a to d)

hello and thanks to everyone for the quick answers.

Julien, you were right. There is indeed a thread that started in 

April 2006 called "Bicycle as a Max/MSP interactive controller ", 

wich seems to have escaped my first searches.

The mouse hacking > hi object solution would of course be the 

cheapest and easiest to execute, and I'll certainly try it first, but 

I'm guessing it won't be as robust and effective as, probably, the 

Has someone really tried with the mouse? Did it work?

Julien, you were right. There is indeed a thread that started in  
April 2006 called "Bicycle as a Max/MSP interactive controller ",  
wich seems to have escaped my first searches.

The mouse hacking > hi object solution would of course be the  
cheapest and easiest to execute, and I'll certainly try it first, but  
I'm guessing it won't be as robust and effective as, probably, the  
hall effect sensors plus magnets.

i used it, but on old school roller skates. worked nicely. you will

have problem with mouse off screen but this can be handled. i used an

old mouse, not the optical one (maybe optical is better as no direct

contact is needed), it was a bit sensitive. all in all, a sensor type

> hello and thanks to everyone for the quick answers.

> Julien, you were right. There is indeed a thread that started in April 2006

> called "Bicycle as a Max/MSP interactive controller ", wich seems to have

> The mouse hacking > hi object solution would of course be the cheapest and

> easiest to execute, and I'll certainly try it first, but I'm guessing it

> won't be as robust and effective as, probably, the hall effect sensors plus

> Has someone really tried with the mouse? Did it work?

i used it, but on old school roller skates. worked nicely. you will
have problem with mouse off screen but this can be handled. i used an
old mouse, not the optical one (maybe optical  is better as no direct
contact is needed), it was a bit sensitive. all in all, a sensor type
setup will be more robust.
are the bike stationery?

On 5/20/07, bragatel rmd74  wrote:
>
>
> hello and thanks to everyone for the quick answers.
>
> Julien, you were right. There is indeed a thread that started in April 2006
> called "Bicycle as a Max/MSP interactive controller ", wich seems to have
> escaped my first searches.
>
> The mouse hacking > hi object solution would of course be the cheapest and
> easiest to execute, and I'll certainly try it first, but I'm guessing it
> won't be as robust and effective as, probably, the hall effect sensors plus
> magnets.
>
> Has someone really tried with the mouse? Did it work?
>
> rd
>
>


or use a camera looking at the pedals, analyse its image and measure 

with Jitter the alternance of changes (e.g. luminance average level) 

when the pedal is in front of the camera;

see Davina project of one of my student on 

http://www.erg.be/erg/spip.php?article263#

or use a camera looking at the pedals, analyse its image and measure 
with Jitter the alternance of changes (e.g. luminance average level) 
when the pedal is in front of the camera;
see Davina project of one of my student on 
http://www.erg.be/erg/spip.php?article263#

-- 
Yves Bernard    yb@imal.org
asbl iMAL vzw
30-34 Quai des Charbonnages
1080 Bruxelles/Brussel
tel 32 2 410 30 93

http://www.imal.org
http://www.erg.be/blogs/artNumeur
http://www.i-cult.be


one more suggestion. may or may not be helpful to you.

i created a patch for a sound installation that used a stationary bicycle wheel to control the sounds based on the speed and direction of rotation of the wheel.

i did this by pointing a camera at the wheel and motion tracking a bright red reflector on the wheel.

it was quite effective and responsive and easy to setup.

if you want, i can dig up the old patch that i used for this and post it. however, i don't think there was anything too brilliant about it, just color tracking in four quadrants. don't think i used any cv objects either, just jitter.

one more suggestion. may or may not be helpful to you.
i created a patch for a sound installation that used a stationary bicycle wheel to control the sounds based on the speed and direction of rotation of the wheel.
i did this by pointing a camera at the wheel and motion tracking a bright red reflector on the wheel.
it was quite effective and responsive and easy to setup.

Or attach in some way a rotary encoder to the wheel - this would solve the

"twisted wire" problem and be really easy to interface to max - just hack a

cheap midi controller that has a rotary encoder. You can then track the

speed of the rotation of the encoder in max easily. This is probably the

> or use a camera looking at the pedals, analyse its image and measure

> with Jitter the alternance of changes (e.g. luminance average level)

> when the pedal is in front of the camera;

> see Davina project of one of my student on

Or attach in some way a rotary encoder to the wheel - this would solve the
"twisted wire" problem and be really easy to interface to max - just hack a
cheap midi controller that has a rotary encoder. You can then track the
speed of the rotation of the encoder in max easily. This is probably the
cheapest and simplest option?

On 20/05/07, Yves Bernard  wrote:
>
> or use a camera looking at the pedals, analyse its image and measure
> with Jitter the alternance of changes (e.g. luminance average level)
> when the pedal is in front of the camera;
> see Davina project of one of my student on
> http://www.erg.be/erg/spip.php?article263#
>
> --
> Yves Bernard    yb@imal.org
> asbl iMAL vzw
> 30-34 Quai des Charbonnages
> 1080 Bruxelles/Brussel
> tel 32 2 410 30 93
>
> http://www.imal.org
> http://www.erg.be/blogs/artNumeur
> http://www.i-cult.be
>

-- 
Jonathan Green
0777 1680 497
jonathan@jg1983.co.uk

You should put something on your bycicle, touching the wheel rays,

producing a rithmic sound (a card for example).

> Or attach in some way a rotary encoder to the wheel - this would solve the

> "twisted wire" problem and be really easy to interface to max - just hack a

> cheap midi controller that has a rotary encoder. You can then track the

> speed of the rotation of the encoder in max easily. This is probably the

> > or use a camera looking at the pedals, analyse its image and measure

> > with Jitter the alternance of changes (e.g. luminance average level)

> > when the pedal is in front of the camera;

> > see Davina project of one of my student on

You should put something on your bycicle, touching the wheel rays,
producing a rithmic sound (a card for example).

2007/5/21, Jonathan Green :
> Or attach in some way a rotary encoder to the wheel - this would solve the
> "twisted wire" problem and be really easy to interface to max - just hack a
> cheap midi controller that has a rotary encoder. You can then track the
> speed of the rotation of the encoder in max easily. This is probably the
> cheapest and simplest option?
>
> Jonathan.
>
>
> On 20/05/07, Yves Bernard  wrote:
> > or use a camera looking at the pedals, analyse its image and measure
> > with Jitter the alternance of changes (e.g. luminance average level)
> > when the pedal is in front of the camera;
> > see Davina project of one of my student on
> > http://www.erg.be/erg/spip.php?article263#
> >
> > --
> > Yves Bernard    yb@imal.org
> > asbl iMAL vzw
> > 30-34 Quai des Charbonnages
> > 1080 Bruxelles/Brussel
> > tel 32 2 410 30 93
> >
> > http://www.imal.org
> > http://www.erg.be/blogs/artNumeur
> > http://www.i-cult.be
> >
>
>
>
> --
> Jonathan Green
> 0777 1680 497
> jonathan@jg1983.co.uk
>
>

In a similar project i used 1 ultra-cheap reed-switch and a few magnets, and measure the time interval between the magnet(s). very simple, very cheap and (at least for my project) very useful.

http://images.google.com/images?svnum=10&hl=nl&gbv=2&q=reed+switch

> In a similar project i used 1 ultra-cheap reed-switch and a few magnets, and measure the time interval between the magnet(s). very simple, very cheap and (at least for my project) very useful.

Very nice! I didn't know about reed switches until now. Great product! 

Jeroen Groot skrev:
> In a similar project i used 1 ultra-cheap reed-switch and a few magnets, and measure the time interval between the magnet(s). very simple, very cheap and (at least for my project) very useful.
>
> http://images.google.com/images?svnum=10&hl=nl&gbv=2&q=reed+switch
Very nice! I didn't know about reed switches until now. Great product! 
To me this looks like a winner.

> I'd look into a Hall effect sensor paired with a magnet or magnets. You 

> really need something hi-speed, and these should be quite accurate. 

> There was a cool project at the NYU ITP department that used that to 

> drive a persistence of vision LED display in the bike wheel spokes.

I would hack one of these cheap tachometers, they use hall sensors, some 

Peter McCulloch schrieb:
> I'd look into a Hall effect sensor paired with a magnet or magnets.  You 
> really need something hi-speed, and these should be quite accurate. 
>  There was a cool project at the NYU ITP department that used that to 
> drive a persistence of vision LED display in the bike wheel spokes.

I would hack one of these cheap tachometers, they use hall sensors, some 
of them are even wireless....

-- 
Stefan Tiedje------------x-------
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tracking a bicycle speed