Syncing Two Motion Axis

[bodoo23]

I geared two axis in studio 5000. The drives are kinetix 5700. My question is that if starting actual position of two axis are same they both work fine with gearing but if one of the axis is a bit slipped somehow before gearing , the gearing always keeps this difference.
For example if both are 75mm and I jog them they both go 90mm. That is fine
but if one is at 80 an the other is 75 before gearing. Final positions are 95 & 90 but I want them to be same like 95 & 95.
Is there any built-in command in gearing for this or Should I do it in plc program by myself ?

Thanks,

 

[Ken Roach]

If you need the axes to travel different distances, you should probably command them independently instead of gearing them together.

Or, you could calculate the difference and gear them with a ratio: if Axis 1 has to go 15mm and Axis 2 has to go 20mm, you could gear Axis 2 to Axis 1 at a ratio of 20:15 = 1.3333.

Ideally, post more about the mechanical relationship and linkage between the two axes.

 

[Peter Nachtwey]

I wish this site would support LaTeX. It is easy. Our site does. Anyway
Assuming both axes are stopped then
v=1.5*Δx/Δt
a=4.5*Δx/Δt²
If Δt is constant for both axes they will get to their destinations at the same time.
this is easy.
It is much harder if the axes are already moving. I have solutions for that too. This is necessary for 3 and 4 knee carriages in saw mills. I had this worked out in 1986 but my current solution is much smoother given all the processing power available now.

 

[kamenges]

You can perform an axis specific move on a geared axis. If you know ahead of time that they are not both in the same location, move one of them to the location of the other then gear them. Or you can gear them and them perform a MAM on the slave axis to adjust it to the master axis. You could even perform the move while the geared move is active. A lot depends on what your system can handle.

Keith