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accuracy of contact sensor ?

asked 2015-05-08 18:36:10 -0500

djou07 gravatar image

updated 2015-05-13 12:43:24 -0500

Hi every body :)

why when I put a link of a model on the ground, its contact sensor indicates that the link don't touch the ground ?

like this graph shows, 1 if link touches the ground, -1 else

the link doesn't move and stay in place. Normally the data of the sensor should be always 1 !

Is this a bug ? If not this means that the if link is not heavy it doesn't touch 100% the ground.I tried to make the link heavier (100 Kg), same problem.

image description


Here is the source code :


CMakeLists.h (change the extension to .txt)

cmd.h (if you want to plot with gnuplot)

the model is in this video. the box is fixed to the ground

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2 Answers

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answered 2015-05-14 02:17:53 -0500

djou07 gravatar image

I resolved the problem by changing the update rate.

First I didn't precise it. By default the frequency is 1000 times per second. So I modified it to 100 and then to 30. And it worked. Still don't understand why it loses accuracy with big frequency...

So, I want to know what is the recommended frequency ?

thanks in advance

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answered 2015-05-13 10:05:18 -0500

niall gravatar image

Some code would help on how you implemented your contact sensor? I had something similar to this and it was because I was reading multiple contacts at the same time. Or maybe your link (box?) is flipping from one corner to another?

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thank you very much for your answer, I updated the question. maybe it will flip if the force applied is not enough. but I set 3 N.

djou07 gravatar imagedjou07 ( 2015-05-13 12:48:58 -0500 )edit
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Asked: 2015-05-08 18:36:10 -0500

Seen: 657 times

Last updated: May 14 '15