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 : Accelerometer study  ( 26912 ) 0 and 1 Guest are viewing this topic.
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 « #15 : February 23, 2009, 09:20:23 AM »

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 « #16 : February 23, 2009, 03:50:12 PM »

Trinko
Sorry, took a while to find:

This is the data sheet from the manufacturer of the accelerometer used inside the Wiimote: http://www.analog.com/UploadedFiles/Data_Sheets/ADXL330.pdf

This is the manufacturers website: http://www.analog.com/en/mems-and-sensors/imems-accelerometers/adxl330/products/product.html

Ben :-)

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 « #17 : February 25, 2009, 10:25:11 AM »

Thanks Ben.

I have reoriented my project. My objective is:
"reconstruction of a trajectory thanks to acceleration measures" that is to say I would like to see if the Wiimote is a good device so as to recreate a mouvement. But the thing is I don't which software I can use in order to do that.

Could you give me some advice?
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 « #18 : February 25, 2009, 04:32:51 PM »

Triniko
Give us more idea of your concept and I will see if I can help
(perhaps an example of what your will text to prove your theory)

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 « #19 : February 26, 2009, 09:11:10 AM »

Ok I will try to be clear (remember I'm French  )

So my idea is to attach the wiimote to a chariot which has one direction and all we know is the theoritical acceleration. Then I would like to get the signals given by the wiimote and "rebuilt" the trajectory by integrating the measures.
But I have big difficulties (I use GlovePIE so as to have measures):

1) Do I have to know something about the calibration of the Wiimote? Because when I put the wiimote on the back, GlovePIE measure +1g on the Y axis whereas it should be -1g on the Z axis, isn't it? (I used this script:

var.t=time*86400

OutputToFile(RemoveUnits(var.t)+","+Wiimote.gx + ", " + Wiimote.gy + ", " + Wiimote.gz)

debug = var.t+', '+wiimote.gx+', '+wiimote.gy+', '+wiimote.gz

2) Once I have the measures, what should I do next? I would like to treat the signals but I don't know how to do that, what software should I use...

Thanks

Triniko
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 « #20 : February 26, 2009, 10:10:13 PM »

Triniko
The +1g is gravity (the Wiimote is theoretically designed in space).

Beacuse you are only looking at a single plain of acceleration, simply ignor all others.

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 « #21 : February 27, 2009, 02:47:51 AM »

Yeah, I know but the problem is that all Websites say that the axis of the wiimote are like here:

and with my script, GlovePIE says that the 1g from earth's gravitational pull is in the Y axis and not in the Z axis (my wiimote is on the table, on the back)
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 « #22 : March 01, 2009, 02:44:09 AM »

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 « #23 : March 05, 2009, 03:35:02 PM »

Hi,

I have emailed Carl Kenner, creator of GlovePIE and he said:

"I tried integrating the acceleration to get velocity and position, butit really doesn't work. The main problem is that you don't know thereal acceleration, because it measures both gravity and accelerationat the same time and it is impossible to separate them exactly. So theacceleration will always be a bit wrong. So the velocity will quicklyget more and more wrong."

I'm in panic because it seems it's impossible to get positions. Do I have to change my way to study the Wiimote?
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 « #24 : March 05, 2009, 03:50:08 PM »

Trinko
Carl is an absolute guru on that sid eof the Wiimote, I would listen to him very carefully. If he says it can't be done, then it proberbly can't be done.

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 « #25 : March 08, 2009, 08:34:43 AM »

well, now I'm lost since i don't find a way to study the Wiimote. The thing is i have to find a purpose, a probem related to the wiimote and that i can solve. Do you have any idea?
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 « #26 : March 08, 2009, 06:15:08 PM »

Trinko
Have you spoken to your physics teacher? Explain what the Wiimote can do, then work backwwards from there.

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 « #27 : May 24, 2009, 05:33:02 AM »

Hi everyone,

I has some acceleration values on each axis of the Wiimote remote.
I'd like to do a double integration in order to have position. For instance, I used the trapezoidal rule but I have weird values of velocity. How can I solve that?

Here are my values (it's a linear motion on the Z axis) acceleration values are in "g", Y axis is upward, Z axis is forward, X axis is on  the right

Time(s)   AccX   AccY   AccZ
0   -0,02   1,04   0,04
0,02   -0,02   1,04   0
0,05   -0,02   1,04   0,04
0,07   -0,02   1,04   0
0,1   -0,02   1,04   0,04
0,12   -0,02   1,04   0,04
0,15   -0,02   1,04   0,04
0,17   -0,02   1,04   0,04
0,2   -0,06   1   0,04
0,22   -0,02   1,04   0,04
0,25   0,02   1,04   0,04
0,27   -0,02   1,04   0,24
0,3   -0,02   1,12   0,4
0,32   -0,11   1   0,44
0,35   0,02   1   0,32
0,37   -0,02   1   0,28
0,4   0,02   0,88   0,36
0,42   -0,06   0,84   0,36
0,45   -0,15   0,8   0,56
0,47   -0,11   1,2   0,48
0,5   0,02   0,92   0,56
0,52   0,06   0,67   0,4
0,55   0,23   1   0,48
0,57   -0,23   0,96   0
0,6   -0,02   0,88   0,28
0,62   -0,28   1,49   -0,28
0,65   0,06   1,08   0,04
0,67   -0,06   0,76   0,04
0,7   0,32   1,37   0
0,72   -0,11   1,24   -0,28
0,75   0,23   1,24   0,04
0,77   -0,11   1,04   -0,16
0,8   0,02   1   -0,04
0,82   -0,11   0,88   0
0,85   0,06   1   0,04
0,87   -0,15   0,71   -0,04
0,9   -0,11   0,88   -0,12
0,92   0,19   1,16   -0,08
0,95   -0,11   0,8   0
0,97   -0,02   1,45   -0,2
1   -0,06   1,29   -0,12
1,02   -0,02   1   -0,08
1,05   0,02   0,84   -0,08
1,07   -0,11   1,12   -0,12
1,1   -0,02   1,24   -0,2
1,12   -0,06   1,16   -0,12
1,15   -0,02   0,92   -0,04
1,17   0,11   1,08   -0,08
1,2   -0,11   0,96   0,04
1,22   0,02   1,24   -0,12
1,25   -0,06   0,88   -0,08
1,27   -0,02   1,24   -0,12
1,3   0,02   1   -0,08
1,32   -0,06   1   -0,04
1,35   -0,06   1,12   -0,08
1,37   -0,06   0,76   -0,04
1,4   -0,02   1,08   -0,08
1,42   0,06   1,08   -0,16
1,45   0,02   1   -0,04
1,47   -0,06   1   -0,04
1,5   0,02   1,04   -0,12
1,52   -0,06   1,08   -0,08
1,55   -0,06   1   -0,08
1,58   0,11   1,08   -0,08
1,6   0,06   1   -0,04
1,62   -0,02   1,04   -0,04
1,65   0,06   1,08   -0,04
1,67   0,02   0,96   -0,04
1,7   -0,06   0,96   -0,08
1,73   -0,02   1,16   -0,08
1,75   0,06   1,16   -0,28
1,77   0,02   1   0,08
1,8   -0,02   1   -0,12
1,83   0,02   0,96   -0,08
1,85   0,02   1,08   -0,12
1,87   0,02   1   -0,04
1,9   -0,02   1,04   0,08
1,92   0,02   1   0,04
1,95   0,02   1,08   0
1,98   0,02   1,08   0
2   -0,02   1,04   0
2,03   0,02   1,04   0
2,05   -0,02   1,04   0
2,08   0,02   1,04   0
2,1   0,02   1,04   0
2,12   -0,02   1   0
2,15   -0,02   1,04   0
2,17   -0,02   1,04   0
2,2   0,02   1   0,04
2,23   0,02   1   0,04
2,25   0,02   1,04   0
2,28   -0,02   1,04   0
2,3   0,02   1,04   0
2,33   0,02   1,04   0,04
2,35   0,02   1,04   0,04
2,38   -0,02   1,04   0
2,4   0,02   1,04   0
2,42   -0,02   1,04   0,04
2,45   0,02   1,04   0
2,47   0,02   1,04   0
2,5   0,02   1,04   0
2,52   -0,02   1,04   0
2,55   0,02   1,04   0
2,58   0,02   1   0
2,6   -0,02   1,04   0
2,63   -0,02   1   0,04
2,65   0,02   1,04   0,04
2,67   0,02   1   0
2,7   0,02   1,04   0,04
2,73   0,02   1,04   0
2,75   -0,02   1,04   0
2,77   -0,02   1,04   0,04
2,8   0,02   1,04   0
2,83   0,02   1,04   0,04
2,85   0,02   1,04   0
2,88   0,02   1,04   0,04
2,9   -0,02   1,04   0
2,92   0,02   1   0
2,95   0,02   1,04   0
2,98   0,02   1,04   0
3   0,02   1,04   0
3,02   -0,02   1,04   0
3,05   0,02   1,04   0
3,08   0,02   1,04   0,04
3,1   0,02   1,04   0
3,13   0,02   1,04   0,04
3,15   0,02   1,04   0
3,17   0,02   1,04   0,04
3,2   -0,02   1,04   0
3,23   -0,02   1   0
3,25   0,02   1   0,04
3,27   0,02   1   0
3,3   0,02   1,04   0
3,33   0,02   1,04   0
3,35   -0,02   1,04   0
3,37   0,02   1,04   0
3,4   0,02   1,04   0
3,42   -0,02   1,04   0
3,45   -0,02   1,04   0
3,48   0,02   1,04   0
3,5   0,02   1,04   0,04
3,53   -0,02   1,04   0
3,55   -0,02   1,04   0,04
3,58   0,02   1,04   0,04
3,6   -0,02   1,04   0
3,63   0,02   1,04   0
3,65   0,02   1,04   0,04
3,68   0,02   1,04   0
3,7   0,02   1,04   0,04
3,73   -0,02   1,04   0
3,75   0,02   1   0
3,78   0,02   1,04   0,04
3,8   0,02   1,04   0
3,83   -0,02   1,04   0
3,85   -0,02   1,04   0
3,88   0,02   1,04   0
3,9   -0,02   1,04   0
3,93   0,02   1   0
3,95   0,02   1,04   0
3,98   0,02   1,04   0,04
4   0,02   1,04   0
4,03   0,02   1,04   0
4,05   0,02   1   0
4,08   0,02   1,04   0,04
4,1   0,02   1,04   0
4,13   -0,02   1,04   0
4,15   -0,02   1,04   0
4,18   -0,02   1,04   0,04
4,2   0,02   1,04   0
4,23   -0,02   1,04   0
4,25   0,02   1   0,04
4,28   0,02   1,04   0
4,3   0,02   1,04   0,04
4,33   0,02   1   0,04
4,35   -0,02   1,04   0
4,38   0,02   1   0
4,4   0,02   1,04   0
4,43   0,02   1,04   0
4,45   0,02   1,04   0,04
4,48   -0,02   1,04   0
4,5   0,02   1,04   0
4,53   0,02   1,04   0,04
4,55   0,02   1,04   0
4,58   0,02   1   0
4,69   -0,02   1,04   0
4,72   0,02   1,04   0
4,74   0,02   1,04   0,04
4,77   0,02   1,04   0
4,79   0,02   1   0,04
4,82   0,02   1,04   0
4,84   0,02   1,04   0
4,87   0,02   1,04   0
4,89   -0,02   1,04   0
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