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I have DC motors, shaft encoders, screws and nuts.
I want to build home made CNC using this parts.
I ask, if I use this motors what can be my cnc's bandwidth?
Yes Electrical time constants, servo controller, Friction and mass of axis plays importand role on BW. Lets forget these parameters.
I will use this motor and other parts (screw, nuts..)
Now i want to know if i use this motors what happens the max axis speed of my cnc? I find an answer for this question but i am not sure, I want learn your ideas.
Motor labels says 3000rpm and screws has 4 mm/rev. (p=4)
We can calculate the maximum velocity of lineer motion.
n=3000/60 = 50 rev.per sec.
vmax = p * n = 4 * 50 = 200 mm/sec.
My machine working area 300x300mm
Now I ask this question: If i want to draw circle with this motors what happens the max speed?
Max radius is 150 mm. (Machine limits)
we know sin and cos functions draw circle.
Function of X axis position
Px = 150 * sin(wt)
Function of Y axis position function
Py = 150 * cos(wt)
we can calculate the velocity functions
Vx=150 * w * cos(wt)
Vxmax = 150 * w = 200 mm/sec
w = 1.33 rad/sec
w = 2pi/T T=2pi/w = 4.7 sec. Appox. 5 sec.
F = 1/T = 1/5 = 0.2Hz
My machine can draw circle (r=150mm) in 5 seconds.
My cnc's position control servo bandwidth must be minimum 02 * 10 = 2 Hz
Am I wrong? I am waiting your responses.
Thanks.
I want to build home made CNC using this parts.
I ask, if I use this motors what can be my cnc's bandwidth?
Yes Electrical time constants, servo controller, Friction and mass of axis plays importand role on BW. Lets forget these parameters.
I will use this motor and other parts (screw, nuts..)
Now i want to know if i use this motors what happens the max axis speed of my cnc? I find an answer for this question but i am not sure, I want learn your ideas.
Motor labels says 3000rpm and screws has 4 mm/rev. (p=4)
We can calculate the maximum velocity of lineer motion.
n=3000/60 = 50 rev.per sec.
vmax = p * n = 4 * 50 = 200 mm/sec.
My machine working area 300x300mm
Now I ask this question: If i want to draw circle with this motors what happens the max speed?
Max radius is 150 mm. (Machine limits)
we know sin and cos functions draw circle.
Function of X axis position
Px = 150 * sin(wt)
Function of Y axis position function
Py = 150 * cos(wt)
we can calculate the velocity functions
Vx=150 * w * cos(wt)
Vxmax = 150 * w = 200 mm/sec
w = 1.33 rad/sec
w = 2pi/T T=2pi/w = 4.7 sec. Appox. 5 sec.
F = 1/T = 1/5 = 0.2Hz
My machine can draw circle (r=150mm) in 5 seconds.
My cnc's position control servo bandwidth must be minimum 02 * 10 = 2 Hz
Am I wrong? I am waiting your responses.
Thanks.