I need to know your encoder value (cpr)or just look at your encoder and give me the P.N. and manufacturer..most are a 200 count that yeilds 800 cpr, but let us not guess.
I need to know the reduction and lead ..I.E.
Reduction = small pully (usually at the servo)
large pully ( usually at the ball or acme shaft)
Just count the teeth on each one
Lead = number of turns the ball shaft or acme shaft turns / inch.
I will need to know this info for all axis.
Then I will plug that into one of my machines and test it, then return the values for you to use.
The top number in the accel tab is just a number that "sets" the maximum accel ( sps). The instructions say to enter the max velocity (sps) ( that is the 3rd line down,) then start velocity, then an accel scale, then pick a number for the top line and start adding zero's untill your accel scale starts from the bottom left and goes to the top right in a smooth line. But before any of this can be done, you must set your axis tab 1st..The maxium sps is a math calculation of the theoritical max rpm of the servo, times the encoder CPR ( I term it "clicks per rev ")divided by 60 = the very maximum sps, but should be 5 to 10 % less to keep the servo amps from faulting.As an example:
encoder cpr= 800 times (*)2700 ( servo rpm)=2,200,000 divided by (/) 60 =
36,666. which represents the maximum sps. I would enter 35000 as the sps.
Look at "Filling Machine Velocities Tabs" by KOLOKITHAS, as he just asked the same questions..I set his values in one of my machines and gave him a conservative set up..He stated it all worked well.
Another way to visulize this is to go to the machine set up ( again) and at the bottom click " Modify Accel ramp", open that and you will understand how the accel ramp is made..do not change that yet untill after you get the machine set up and running, but it is fun to go back and customise your accel ramp once you know what your machine dynamics are.
Once you get past the accel values and the rest of the set up, you will really like Desk CNC..it is smooth, has look ahead, the screen although not jazzy, has everything you need to run a 3 or 4 axis machine safley. Depending on the type of servo amps used, you can run some real high IPM in GOO.
Anyway, get the info, I will set it up and give you the info.
Adobe (old as dirt)  |