Dual motors on y axis create noise and oscillation
Posted: Mon Nov 11, 2019 1:02 pm
I have an acorn rev3 connected to dmm dyn4 1kw drives and motors .
It’s for a 5x10 router table with two drives on y axis.
My auto tune of z and x performed great.
Y axis I cannot auto tune because you can’t tune both motors at once.
I think my gantry and z axis weigh about 600lbs total. Its got 18” of gantry clearance and it made of cast iron and steel and aluminum 1/2” plates.
When I jog the axis in cnc12, it moans and groans as it moves and eventually both motors will go into fault.
My gantry is square, I moved it 5 feet from side to side and it never moved a millimeter.
What’s odd is that if I disconnect either one of the motors, the single motor runs smooth without feedback. It will go into fault when asked to fast jog at 100 Ipm but that’s to be expected of one motor doing 2 motors work.
Why do the pair of motors together create such feedback and resistance to one another even though the gantry is square and smooth moving, and the y axis is certainly reversed for the second motor in the Cnc wizard.
I’ve been trying these values on my motor tuning :
Main gain 40, speed gain 40, integral gain 1 - creates noise, oscillation, then fault
Main gain 48, speed gain 43, integral gain 1 - creates more noise, more oscillations and sooner fault
Main gain 40, speed gain 40, integral gain 5 - same noise and oscillation, might have faulted soone
Main gain 55, speed gain 55,integral gain 1 - tremendous noise and oscillation. Fast fault time
My x values are 48,43,1 and that was what the auto tune feature came up with. It’s smooth but has some slight noise. I figured my x axis weighs about half of the gantry total weight, so each of the y axis motors should be a bit stronger in gains than the x?
Also , I’ve had cnc12 set to 200,000 steps per and by switching to 100,0000 I get half as much noise, and switching to 400,000 steps makes it impossible to operate
It’s for a 5x10 router table with two drives on y axis.
My auto tune of z and x performed great.
Y axis I cannot auto tune because you can’t tune both motors at once.
I think my gantry and z axis weigh about 600lbs total. Its got 18” of gantry clearance and it made of cast iron and steel and aluminum 1/2” plates.
When I jog the axis in cnc12, it moans and groans as it moves and eventually both motors will go into fault.
My gantry is square, I moved it 5 feet from side to side and it never moved a millimeter.
What’s odd is that if I disconnect either one of the motors, the single motor runs smooth without feedback. It will go into fault when asked to fast jog at 100 Ipm but that’s to be expected of one motor doing 2 motors work.
Why do the pair of motors together create such feedback and resistance to one another even though the gantry is square and smooth moving, and the y axis is certainly reversed for the second motor in the Cnc wizard.
I’ve been trying these values on my motor tuning :
Main gain 40, speed gain 40, integral gain 1 - creates noise, oscillation, then fault
Main gain 48, speed gain 43, integral gain 1 - creates more noise, more oscillations and sooner fault
Main gain 40, speed gain 40, integral gain 5 - same noise and oscillation, might have faulted soone
Main gain 55, speed gain 55,integral gain 1 - tremendous noise and oscillation. Fast fault time
My x values are 48,43,1 and that was what the auto tune feature came up with. It’s smooth but has some slight noise. I figured my x axis weighs about half of the gantry total weight, so each of the y axis motors should be a bit stronger in gains than the x?
Also , I’ve had cnc12 set to 200,000 steps per and by switching to 100,0000 I get half as much noise, and switching to 400,000 steps makes it impossible to operate
and yep good advice to call DMM on how to tune thier drives. post photos of the machine to an album and place link here ..this may shed some light on the subject as well.