gavspav

I'm hoping to track where a ping pong ball hits the table during a live game of table tennis.

I'm intending to use an array of Piezo transducers and calculate the position of impact by calculating the time the signal takes to travel to each mic ie triangulation.

Does anyone have any experience relating to this. Do you think it would work? Would I need to do some kind of analysis rather than just timing?

To make matters worse I am totally inexperienced with maxmsp! I have however used pd before as well as several other node based software environments.

Any links, tutorials, help, anything would be greatly appreciated!

I'm hoping to track where a ping pong ball hits the table during a live game of table tennis. 

motion-tracking-using-piezos

It is possible as this project does precisely the tracking you're

http://tangible.media.mit.edu/projects/pingpongplus/

It is possible as this project does precisely the tracking you're
suggesting: http://tangible.media.mit.edu/projects/pingpongplus/

That's pretty much exactly the same thing that I wanted to do though.

Always a source of debate in my own head - is it worth creating something that's been done before.

On the one hand I've never made it before so I'm sure I'd still get alot out of it. Similarly assuming I delivered the project, people would enjoy it.

On the other maybe I should spend my time creating something which has never been seen before!

That's pretty much exactly the same thing that I wanted to do though.
Which begs the question should I bother?

Always a source of debate in my own head - is it worth creating something that's been done before. 

> On the one hand I've never made it before so I'm sure I'd still get 

At college level (which, IMS, is the context here), doing stuff 

yourself and getting a lot out of it is (almost always) the most 

When you're writing your PhD or in industry or working as a freelance 

artist, then originality and uniqueness become increasingly an issue.

There are exceptions and not-alwayses. Copland wrote a nice article 

once about Ravel & Debussy *not* being the first orchestral 

impressionists: there was an obscure composer a generation earlier 

using very similar techniques. But Ravel & Debussy did it more 

Peter Castine +--> Litter Power & Litter Bundle for Jitter

iCE: Sequencing, Recording & |home | chez nous|

Interface Building for |bei uns | i nostri|

> On the one hand I've never made it before so I'm sure I'd still get  
> alot out of it.

At college level (which, IMS, is the context here), doing stuff  
yourself and getting a lot out of it is (almost always) the most  
important point.

When you're writing your PhD or in industry or working as a freelance  
artist, then originality and uniqueness become increasingly an issue.

There are exceptions and not-alwayses. Copland wrote a nice article  
once about Ravel & Debussy *not* being the first orchestral  
impressionists: there was an obscure composer a generation earlier  
using very similar techniques. But Ravel & Debussy did it more  
compellingly.

--------------    http://www.bek.no/~pcastine/Litter/    -------------
Peter Castine             +--> Litter Power & Litter Bundle for Jitter

I have a travelling interactive entertainments show which i take to 

If you're interested see www.boredbrand.com

Originality is kind of important to me but not as important as creating work which enables people to have an experience.

I have made things in the past which were completely unoriginal (though I only found out afterwards.)

I guess really it depends if you add anything of yourself to the concept/project.

Anyway I've mailed the people who made the original and asked them what they thought!

I have a travelling interactive entertainments show which i take to 
events. 

If you're interested see www.boredbrand.com 

If you watch the videos, its technically interesting, and fun to watch, 

There is your chance to make it better. There must be more than proof of 

concept, this stuff could need an artistic expression which stands out 

Go for it, as long it makes sense for you...

If you watch the videos, its technically interesting, and fun to watch, 
but has a lack of artistic content.
There is your chance to make it better. There must be more than proof of 
concept, this stuff could need an artistic expression which stands out 
as a work of art on its own.

  [][]  [][][]  [][]  [][][]
[][][][][][][][][][][][][][][]

         Stefan Tiedje
         Klanggestalter
     Electronic Composition
               &
         Improvisation

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     ))))) )|  |  |( \
     ///     _/)/ )))))
             ___/   ///

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-- _|_)----|-----()-----------
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94320 Thiais, France
Phone at CCMIX +33-1-57 42 91 09


Seeing as I am an MSP newbie I'm gonna go with it for a while and see what happens.

Two microphones. If the volume on either rises above a certain amount, I trigger a bang and start the timer object.

When the other mic rises above the threshold I trigger the other side of the timer.

Thing is the timer always reads 0. Well sometimes it reads 100.

So I guess I need to learn some basic theory about sound.

The frequency is 44100 times a second. Does the computer receive 44,100 messages every second?

It doesn't does it. Presumably there is some kind of resolution.

And how is this related to the setting of audio buffers?

I feel slightly embarassed about posting my patch which is really only an example patch changed a tiny bit but here goes.....

As far as I can tell a knock which reaches one microphone first should trigger the time difference when it reaches the other mic.

The signals appear to be occurring at the same time and I seem to be getting data into max only 10 times a second.

I know I am missing some simple piece of knowledge!

> The signals appear to be occurring at the same time and I seem to be

> getting data into max only 10 times a second.

Have a look in meter~ inspector : by default, interval is set to 100 ms.

Maybe you should use peakamp~ instead of meter~ to be sure to miss

> The signals appear to be occurring at the same time and I seem to be
> getting data into max only 10 times a second.

Have a look in meter~ inspector : by default, interval is set to 100 ms.
Maybe you should use peakamp~ instead of meter~ to be sure to miss
nothing...

Thanks for your help. I never knew about the inspector.

You're right anyway using the meter is kind of pointless.

Thanks for your help. I never knew about the inspector.
You're right anyway using the meter is kind of pointless.
I'll have a look at peak meter

any news how to get good coordinates in the table?

How did that went?
any news how to get good coordinates in the table?


Motion Tracking Using Piezos