Index Homing odd offset

PCW wrote: Did you change these parameters?

MAX_VELOCITY = 5.0
(5 IPS = 300 IPM)
STEPGEN_MAXVEL = 6.0
(25% headroom)

if not, a following error would be _expected_ at just about 75 IPM
since the stepgen_maxvel was set for 1.25 IPS = 75 IPM

Yes, I changed them.

Okay, so the P parameter is not 0-100%. I will try again.

At what feed should I test the increase in P? For now it's 60 ipm, I can go as far as 10 to 1000 on the P, below P 10 the motor sounds off.
P at 100 and 90ipm, I get joint following error with violent oscillations. This is on the x with no load. I don't get the oscillations on the Z with heavy slide and same settings.

Come to think of it, the DMM's have their own internal pid that should get adjusted to the load of the axis first. I need to look at that via their software.

OT-CNC wrote: P at 100 and 90ipm, I get joint following error with violent oscillations. This is on the x with no load. I don't get the oscillations on the Z with heavy slide and same settings.

The PID settings depend on the mechanics of the system, so the settings will be different for a heavy axis than a light one.
(In principle you ought to re-check the PID with a heavy workpiece....)

It sounds like P=100 is too high for X, though you might be able to kill the oscillations with some D. (typically D is a very small number)

I would expect the controller to mainly be using FF1 and [strike]I gain.[/strike]. Sorry, for a velocity drive like you have, it will be Pgain.

I changed a value in the ini file and don't have the joint following errors any more.
I changed the MAX_OUTPUT=1.25 to MAX_OUTPUT=0 (This is the setting between deadband and encoder_scale under axis_2.)
Is 0 an acceptable value for the way I'm controlling my drives? I'm now up at 300 ipm with no following errors. I left the P at 50 for now.
Still need to spend time with halscope to see what's going on.

OT-CNC wrote: I changed a value in the ini file and don't have the joint following errors any more.
I changed the MAX_OUTPUT=1.25 to MAX_OUTPUT=0 (This is the setting between deadband and encoder_scale under axis_2.)

That sounds very unlikely to be correct, but it is hard to say without knowing what that parameter is being used for in the HAL file.

So, what is that parameter being used for in the HAL file?

At a first guess you are turning your PID loop completely off...

Actually that's OK.
A max_limit of 0 means the output is not limited at all
a max_limit of 1.25 means a 75 IPM limit on PID output (velocity)