Calibration Problem With A Axis >HELP Please<

Have you tried lower velocity and or lower acceleration?
I assume you are not using Backlash compensation.

Rick G

Rick G wrote: Have you tried lower velocity and or lower acceleration?
I assume you are not using Backlash compensation.

Rick G

Hi Rick!

I have tried out lower velocity and lower acceleration, but both changed nothing.
I don't use backlash compensation, becaus i thought that I should not have a backlash.
I tried to move the A axis under "1/2 holding torque" but there is no possibility to move the axis.
I use a motorbike chain Gear. Maybe there is a backlash I don't recognise, but if there is one I can't work accurate with the system because the error is not equal. (Between 1°-0,2°).
I need to research into this topic.
What do you think?.

it's ok Sergio,
dont worry over language .

remember a stepper moves only in 1.8degree steps , and cannot stop inbetween , microstepping can help but is not the real answer , if the stepper moves to a position but the ratio of the pully is not totally divisable by 360 , you will get a remainder of the value , over a large number of steps this can become so large that it is noticed ( as is what you you are seeing )

so you need to find a ratio that will divide the number of steps , equally into 360 degrees , with no remainder .
if you look up information on rotary tables this is well noted .

also if your using a microstepping drive , you will find it better to use the full or half step settings .
as this gives you more torque for holding a position ,
this is more of a mechanical problem & mathmatics than software or electronics unfortunately .

what steps setting are you using ?

Hi Sarah!

At the moment i use 1600 on my driver and on the Software.
Also full step setting
72°/rotation without or instead of the option of gear reduction.

By now i communicate with my gear supplier and he told me that i should have a little backlash with the chain and i should use a belt drive to reduce this error. So maybe i have two problems wich result in one error.

I think i'm to confused for that issue.
I can see that i need 22,2steps for one degree and I think this is just theoretical, so i can just reach 0,99° or 1,03°. And my error in ressolution should be 0,04°.
Can you please calculate a example for me?

Hello,
I have not worked with rotary axis much in the past.

However a couple thoughts.
When working with chains in the past they seem sometimes be be tighter or stretched more in some sections.
That is if you adjust the chain tight and then turn the sprockets to a different location you might find it now loose or very tight.
So the result is may not be actuality linear for that section. Of course the sprockets may also have run out.

A micro steeping drive will attempt to hold a stepper in between steps if command to but as cncbasher pointed out it may not be exact.
At a 5 to 1 ratio this will be more apparent than say a 10 to 1 ratio so the lower the ratio the more any stepper inaccuracy will effect the outcome. A higher ratio may help.

If the error is cumulative a 3,600 deg. move should be off by more than a 360 deg move .

Rick G

Hi Rick!

Ok, this would explain the evolution of the error.
So i think i have to change the Gearsystem to beltdrive and hopefully this will solve the problem.
I will report after finishing the change.
In case of divisibility i just should use a gear as big as possible.
So maybe i can put in a 1:6 gear. 1:10 is to big for my System.

Thank You!