Modest request for next Jaguar firmware

[Joe Ross]

Originally Posted by Levansic

My team is using LabView, and we haven't found an equivalent for the enable and disable command for individual CAN jaguars. Perhaps there is a terminal on one of the vi's that we missed.

It's built into the Motor enable/disable VIs.

Originally Posted by Levansic

If you look at limit switches, for example, there is no way to enable or disable them from LabView. They are explicitly enabled by default, so you do not have to send an explicit command to enable them on the Jaguar. If you use BDC-Comm, you can disable or enable the limit switches. The FIRST Labview libraries take this choice (or responsibility) away from the student programmer, and make the limit switches always functional. No code required.

If there are existing CAN messages that you think should be implemented in the LabVIEW library, you can file a bug report on first forge http://firstforge.wpi.edu/sf/tracker...b_labview_bugs

You can also implement them yourself, using the the documentation that rrossbach pointed you to.

I do think that the choice to switch out of a closed loop mode into an open loop mode when 0 is commanded is better left to the programmer, rather then being built into the jaguar, because I think both options are correct, for different circumstances.

I do think having encoder filtering is something that should be implemented inside the jaguar.

[Levansic]

I used the limit switches as an example, because it appears that there was a conscious decision by the WPI implementors to provide a default safe mode.

On the jaguars, I see that there is inconsistent behavior already with regard to the jaguar being commanded to a 0 set point. For example, if you use voltage mode with a ramp rate, and have the brake set by jumper or CAN specification. You can ramp to 100%, and then immediately ramp down to -50% or -100%, but as soon as you command a voltage between ~-10% to 10%, the brake kicks in immediately, with no ramp. A near 0 commanded voltage ignores the ramp rate that is set. Likewise, with the brake set to coast, there is no ramp down to 0, it just free-wheels.

In speed control mode, the jaguar is attempting to control the output, even if commanded to 0. My proposal would at least synchronize the behaviors of these two modes.

[Levansic]

Originally Posted by Joe Ross

It's built into the Motor enable/disable VIs.

OK. Wasn't aware that those were polymorphic.


Thanks for the link for WPI feedback! Also, thanks to rossbach for the CAN documentation link. We will go through the CAN reference to see what we are missing.