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Unread 02-10-2009, 09:47 PM
hellochar hellochar is offline
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accelerometer reads infinity

we've had a new problem with our accelerometers that have only recently appeared. Using labVIEW:

1) On our first run of the robot, the accelerometers will read infinity for all axes
2) We then stop the code and re-run it. This time, the accelerometers work correctly for a few reads - three to five readings - and then stops altogether. other sensors still read values
3) We then stop the code and re-run it again. This time, accelerometers work fine.

It repeats this pattern over and over again. we haven't changed any accelerometer initialization/reading code for a while, although we did have to re-sodder the PWM wires a few days ago. I would consider this to be the cause of the problem, but how would a hardware/wiring problem create a deterministic loop?
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Unread 02-11-2009, 01:48 AM
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Re: accelerometer reads infinity

Obviously this indicates that your robot has zero mass.

Sorry, I know you were looking for a more helpful answer than that. Have you tried using a multimeter to read the voltage on the accellerometer leads? That might help determine whether the problem is in the accellerometer or in the cRio software.

Jason
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Unread 02-11-2009, 07:06 AM
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Re: accelerometer reads infinity

In addition to seconding Jason's advice, I would suggest posting your code here. It sounds to me like software.
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Unread 02-11-2009, 09:10 AM
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Re: accelerometer reads infinity

Are you traveling at or near the speed of light?

What is your scaling factor or rate set to? Could there be a divide by zero somewhere?
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Unread 02-11-2009, 10:09 AM
Jranko311 Jranko311 is offline
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Re: accelerometer reads infinity

Are you dividing by zero anywhere in your code?
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Unread 02-11-2009, 05:26 PM
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Lightbulb Re: accelerometer reads infinity

haha fixed the problem. the protons were going too fast
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Unread 02-11-2009, 07:47 PM
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Re: accelerometer reads infinity

Quote:
Originally Posted by hellochar View Post
haha fixed the problem. the protons were going too fast
Whenever you have a problem and a solution, please make an effort to post them both. This will help other teams in your position later.
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Unread 02-11-2009, 08:15 PM
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Re: accelerometer reads infinity

ahh, apologies. the problem was just a low battery .. what protons?!
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