TCP 5-axis kinematics

Hi Aciera,

Yes, this machine does use absolute encoders, the signal comes from the encoder itself.
So the rot-point values I haven't changed at all, should I?

If I give 'G53 X0 Y0 Z0 A0 C0' then the X, Y moves and A and C axis rotates so that the spindle is perpendicular to the bed (C-axis). The spindle is at a height of 215mm above the center of C axis.

If I had to get the spindle to touch the center of the bed (without a tool) I would give the command 'G53 X0 Y0 Z-215'?

So I'm sharing a video demonstrating the behavior of TCP when I jog the a-axis clockwise and anti clockwise:
share-me.video/video/afm0SUWVEc2Fgm6fgZ9...HQp5wkDMt12V3nfJRUxs

The problem is more that the Z-axis seems to be moving in the opposite direction more than the tracking being off.

Regards
Abhishek

Ah, yes that is what I suspected. Since your '(x,y,z)-rot-point' values are all zero you are telling the kinematic that the the machine reference point is also the face center of your c axis table.
This is from the file xyzac-trt.txt as found in the folder 'configs/sim/axis/vismach/5axis/table-rotary-tilting':

Hal Input pins:
  xyzac-trt-kins.x-rot-point
  xyzac-trt-kins.y-rot-point
  xyzac-trt-kins.z-rot-point

X, Y and Z rot-point pins represent the
offsets of the center of rotation of the C axis
relative to the machine absolute zero

So in your case you would need to set 'xyzac-trt-kins-z-rot-point' to -215. Really I would suggest to put a dial indicator in the spindle and probe the face center of your rotary c and put the found absolute coordinates into the (x,y,z)-rot-point settings.

Oh my goodness!!! I feel like such an idiot.

Thank you so much, it now seems to be working much much much more like how its supposed to haha.

But now I have another doubt. image missing /media/kunena/emoticons/unsure.png

The Z-axis is moving correctly as you can see in this video.

share-me.video/video/2w89jeZMNxtPSMUP5FT...MN6DRxcpXd3bBT3Cx2CA

But this is assuming that the component is level with the bed...
Now how do I get it to follow when a component is mounted on a fixture. I mean the Y axis doesn't seem to compensate enough right now....

P.s. yes ofcourse I will surely use a dial indicator when fine tuning the configurations image missing /media/kunena/emoticons/smile.png


 

Hmm, that doesn't look right. Maybe try 'z-rot-point' value the other way around (ie 215 instead of -215).

[edit]
I just changed the 'xyzac-trt' sim config to a machine that homes 215mm above the center of the rotary c table and it seems to be working fine with these settings in the ini file:
So I'm not sure what's going on in your configuration.

 

I turned it around, I think -215 had better results, here's a video with z-rot-offset as +215
share-me.video/video/yWIw9ESuXrIFjNeZHlb...vjHCGjgxgOUg5JAwmlKP

Any other suggestions to fix this problem