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Unread 02-24-2011, 12:04 AM
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Re: 1 Encoder, 2 Jaguars

Quote:
Originally Posted by otherguy View Post
We tried it today. W/ our quadrature encoders (don't know the part number off the top of my head). All pins of the encoder were wired to one JAG then GND, A & B were jumppered over to the 2nd JAG. Implementing position control (implemented on only one jag - 2nd jag was not commanded) resulted in wild responses (motors continued spinning when they showed they had reached their destination). Removing the jumper to the 2nd JAG instantly resolved the problem. We didn't spend time trying to diagnose the problem, just moved on to the below. My uneducated guess is that these inputs need to be isolated. If anyone else is successful in wiring these, please share your solution.

EDIT: maybe this is our problem? http://www.chiefdelphi.com/forums/sh...9&postcount=16

We did however have good luck setting one jag up w/ PID position control (MASTER - wired to the encoder). The other JAG (SLAVE) was commanded using the %V bus mode. Inputs to the slave were the voltage output from the master controller. Sync groups were used to coordinate outputs. This seemed to work well in our tests. Our voltage output curves looked quite clean compared to some of the graphs which I had seen reported in other posts. We're going to continue this route as long as we don't start seeing any problems.

Tomorrow we'll move onto speed control.
We never attempted this for position control, but I can confirm that you'll probably need the optoisolator as Hugh states...load on the CIMs certainly causes issues we did not see under much less load.

We made several PCBs to provide this isolation and I'm frankly not sure of any rules that prevent them, as long as they take power from the sidecar or the Jaguars.

If I read your post correctly, you didn't actually enable one Jaguar? Why?

Last edited by techhelpbb : 02-24-2011 at 12:23 AM.
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