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Unread 20-02-2011, 21:47
Jonathan Norris Jonathan Norris is offline
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Re: Jaguar Issues...

Quote:
Originally Posted by EricS-Team180 View Post
seen this before! ..... we had the same problem last year while using a CAN bus and a Jag for position control on a swerve drive. You need to find a way to flatten the voltage spikes. What worked for us was to apply a 20msec rate limit to the position request to the Jag. As a back-up we came up with a function (tied to a joystick button) to save the encoder readings, disable the Jags, and re-enable them.

At what rate are you making the speed requests? The older IFI controllers ran at something close to 26msec.

Eric
Thanks for your suggestions we are going to try the button to disable and re-enable. We just slowed down our requests by 4 times and are still seeing issues.

We see these issues on fresh batteries almost instantly some times, our drivetrain setup is pretty standard and wouldn't be drawing an abnormal amount of current. Our arm is also balanced with a gas spring so it's motor doesn't have to work hard. I would say that we are not drawing an abnormally large amount of current, thus probably not dropping our voltage that low.
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