Hi,
OK reran the x axis tuning with no dead band and turned down I gain to 0.01 and got a much "flatter" error curve. These are my final settings:
Code:
ch0->Vel=40;
ch0->Accel=3;
ch0->Jerk=50;
ch0->P=170;
ch0->I=0.01;
ch0->D=0;
ch0->FFAccel=0;
ch0->FFVel=0;
ch0->MaxI=2000;
ch0->MaxErr=200;
ch0->MaxOutput=2047;
ch0->DeadBandGain=0;
ch0->DeadBandRange=0;
Moving to the Y Axis, as mentioned above this VFD only accepts 0 to 10V+. I configured the VFD for "joystick" mode with a range of 1v-10v, so 0v doesn't result in full reverse. 9v/20v = 0.45 gain, offset 5.5v, converted to DAC counts 5.5v x 2048/10v = 1126.4. I had to set the Output Channel gain and offset to -0.45 and -1126.4. Otherwise the output voltages were negative.
This axis can move much faster however I've tuned it with lower velocity and acceleration than it's capable of. If there are disadvantages to doing that I can go back and refine the higher speed tuning. For now I've tuned it using the same V and A as the x axis. Resulting plots show similar characteristics to the X-Axis... perhaps it's a setting in the VFD that I can eventually figure out to get the change in direction to occur nicer.
Attachment 337534
Final settings:
Code:
ch1->Vel=40;
ch1->Accel=3;
ch1->Jerk=50;
ch1->P=60;
ch1->I=0.005;
ch1->D=0;
ch1->FFAccel=0;
ch1->FFVel=0;
ch1->MaxI=2000;
ch1->MaxErr=200;
ch1->MaxOutput=2047;
ch1->DeadBandGain=1;
ch1->DeadBandRange=0;
ch1->InputChan0=1;
ch1->InputChan1=0;
ch1->OutputChan0=1;
ch1->OutputChan1=0;
ch1->MasterAxis=-1;
ch1->LimitSwitchOptions=0x100;
ch1->LimitSwitchNegBit=0;
ch1->LimitSwitchPosBit=0;
ch1->SoftLimitPos=1e+09;
ch1->SoftLimitNeg=-1e+09;
ch1->InputGain0=-1;
ch1->InputGain1=1;
ch1->InputOffset0=0;
ch1->InputOffset1=0;
ch1->OutputGain=-0.45;
ch1->OutputOffset=-1126.4;
The one thing that came up is that this axis is moved via cables, occasionally the cable may bind a bit as it is wrapping around the winch drum. This results in a bit of vibration, seen here at ~ 44 & 50 seconds:
Attachment 337540
Is there any way to filter this out without affecting the overall accuracy? I've done the tuning without the main motor running, once it is there is a bit of vibration as the big wheels are not balanced as well as they should be. Hopefully this doesn't end up being a problem.
My next step was to rig up a pen to trace the movement and then begin testing with KmotionCnC.
Thanks again.