# Thread: Moving axis independently. EMC2

1. ## Moving axis independently. EMC2

I do not know if anyone tried this before, but here goes. The machine I made has three axis. But not in a standard x y z config. Instead it would be more correct to say it has a x1 x2 and x3 axis, as they are inline with one another.
For ease of explanation I will call them x y and z. Starting from the left x axis with a travel of 1700mm then the z axis on the same linear track with a travel of 250mm and lastly the y axis, also on the same linear track with a travel of 1700mm. This odly arranged system must feed 32mm diameter tubes 1400mm long continiously. ie The chuck on the x axis grabs the tube and feeds it approx 1000mm, at that point the chuck on the y axis grabs the other end of the tube and starts moving WITH the x axis at the same speed and continue moving. The x axis then returns home rapidly, to grab the next tube, to feed it right behind the first tube. The idea is to get a continious feed with short lenths of pipe.
I have set up the stepper motors and gheko drives with a computer running EMC2. All works well. But the problem is: I cannot get the x axis to return home while the y axis is moving. G CODE only does the function in that line, and it does not like two g codes ie 001 G01 X1700. F2000. Y1000. F240.

QUESTION: Has anybody tried this with EMC2? To move 2 or 3 axis independently from one another without the program interpolating the movements. And if so, I would really like to know how you did it.

WHAT I TRIED: On the simulation Prof Rudy and myself managed to change the ini and hal configeration to accept TWO jog commands. Which should allow one to jog forward at say F400. and return home at F4000. If you combine the reverse contact on the parralel port with a SCALE switch.
ie pin 4 closed=jog forward (F400.) pin 5 closed=jog backward (F400.) And pin 6 closed=Scale x10. (Same as on your MPG control)

WHAT I WOULD LIKE TO KNOW: Is there simpler software that can do these movements, it seems to me that EMC2 is over kill for what I want. Can any one help me please?

2. If you do not need coordinated motion - I would look at using just hal and classic ladder. The hal portion of emc can be run by itself. Then just have some stepgens running controlled by maybe ladder logic. (just thinking out loud)

sam

3. Thanks Sam, a few people I spoke to, agrees with you. The only challenge would be to get the movement to still accellerate and decellerate smoothly with "ramps".
Do you perhaps know how to write that ladder?

4. If you are using steppers - you can set the acc. So whatever you send it - it will only accellerate at the rate set in the stepgen. In hal there are things like limit3 componants that limits acc/vel

LIMIT3

Great manual
EMC2 Documentation - HTML version

sam

• Thx sam, I will check it out.