Command derivative

Due to bug fixes in the PID component, its probably best that pncconf connects no signals to the PID command derivative pin

for example

net x-vel-cmd => pid.x.command-deriv

if x-vel-cmd is unconnected elsewhere, will lead to a non-working FF1 PID term

and

net x-vel-cmd => pid.x.command-deriv
net x-vel-cmd <= joint.0.vel-cmd

Has problems due to the lack of synchronism with the PID
with the necessary pid.n.error-previous-target setting

Starting in 2.8?

The PID bug was fixed in 2.8 so 2.8 is good, but doing this for all versions would
not be harmful

It looks like this is correct in 2.9s pncconf. Not sure what version the forum poster
used or whether they had disconnected the pin by leaving the signal connected
to the PID component but not connected to joint.n.vel-cmd. Doing this makes the PID
loop untunable since the PIDs cmd-deriv pin will be used (since its connected)
but the FF1 term will not work

The bug that was fixed was that the PID component was supposed to internally
calculate the commanded and feedback velocities if its cmd-deriv pin or fb-deriv
pins (respectively) were not connected, but it turned out that this feature only
worked on fb-deriv. That is, the command-derivative (used to calculating the FF1 term)
was always calculated internally regardless of whether the PID components
cmd-deriv pin was connected or not.

Looking at the code - I have already done this in 2.8 +.
git hash dc1574085

Thanks!

Chris

Great, thanks for the update.