I guess the core of the calibration difficulties is which variable do I change to correct issues. I have spent the last 4 months experimenting with this; systematically testing all of the variables to see how it effects the geometry. There are 10 variables per arm. This becomes interesting/maddening when you change a variable that you wound expect a change in geometry and after leveling the plane, nothing changes.:S
So enough venting, here is what I am doing about this.
Spreadsheet simulation
I have made a spread sheet that simulates the calculations using all of the variables. I feel really stupid for not doing this in the first place. Now i can see variable changes without 20-30 minutes of configuring.
calibration circle
A printable circle with 90mm radius and 120 degree lines. Print this out and align it with the nozzle center and the back-middle arm minimum position (0x90) to see geometry issues.
Measure measure measure
Something like this is extremely helpful for measuring nozzle height and effector arm heights.
[www.harborfreight.com]
A compass is also helpful for comparing actual arm angle with the angle given in the spread sheet.
With all the measurable values correct, the only variables that can change your XY geometry is the SIN and COS of your vector radius or the distance from the center to the shoulder attachment.
So where am I at? I have all the minimum arm vectors aligning with my calibration circle, I need to do some more calibration on the maximums.
Here is a vid of the minimums.
[www.youtube.com]
So enough venting, here is what I am doing about this.
Spreadsheet simulation
I have made a spread sheet that simulates the calculations using all of the variables. I feel really stupid for not doing this in the first place. Now i can see variable changes without 20-30 minutes of configuring.
calibration circle
A printable circle with 90mm radius and 120 degree lines. Print this out and align it with the nozzle center and the back-middle arm minimum position (0x90) to see geometry issues.
Measure measure measure
Something like this is extremely helpful for measuring nozzle height and effector arm heights.
[www.harborfreight.com]
A compass is also helpful for comparing actual arm angle with the angle given in the spread sheet.
With all the measurable values correct, the only variables that can change your XY geometry is the SIN and COS of your vector radius or the distance from the center to the shoulder attachment.
So where am I at? I have all the minimum arm vectors aligning with my calibration circle, I need to do some more calibration on the maximums.
Here is a vid of the minimums.
[www.youtube.com]
