Hi all
I`ve been lurking in the shadow`s for a while.
Sins i`m quite new to cnc in general, and don`t want to ask any
darn right annoying questions that the veterans here are more than tired of answering. (thers supposed to be a smily here but din`t get that function to work)
Anyhu, i Must credit you bruce for creating the cnc brain.
Even though there are hundreds of controllers and breakout boards.
It doesn`t seem to be any product coming even close to yours.
All honors to you.
Even though i have two suggestions for improvements.
The first one demands little explanation. It might even have ben mentioned previously in this thread. (feel free to verbally abuse me if that is the case.)
Right, the cnc brain as it is at present supports 6 axis. And this is fine for most applications, but if one where to build slightly more advansed systems.
Like if one wanted to add a automatic tool changer etc you migt want atleast one or two more axes. So a possibility to supplement with one or more cnc brains to achieve 12, 18 or 600 axis if one felt like it. Only limit would be the number of usb ports on the computer.
So for the second and most interesting thingy. The tripple closed loop option.
This was an idea that came to me, as i tried to figgure out how to level the rails on "hudge" machinery. You see i own a company that manufacture varius items in fiberglass. Among others hudge (13 by 3,5 m) flat panels with intricate cutouts. And then to achieve high accuracy. With the lengths of rails required to machinery of this sise isnt easy. I'm even fiddling with the thought of milling casting moulds out of aluminium in sisabl dimensions. Meaning even higher accuracy is required. And today it came to me how to possibly not fix the problem but making it smaller. Now the system i am going to revele and explain might possobly help to increase accuracy on smaller machinery.
Note: i haven't tested the theory. Pluss i don't know if something like this already exist. And even though it all seems ingenius in my head. It might aswell be comlete Crapadudle.
Anyhu.
The cnc brain currently has a double closed loop system that littelay means that you know the whereaboutst of the "slead" in the moving direction.
Shown in picture one. With the help of rotary encoders or linear scales. Plus a rotary encoder mounted on the motor shaft.
Attachment 65994
Now what i'm suggesting is to know the whereabouts of the "slead" in two new directions shown in picture 2. A so called tripple closed loop.
And how are we gonna do that. We are gonna achive that with a 20$ laser pointer and something like a 200$ web cam.
The setup is shown in picture 3
Attachment 65997
Now what we do is we measure so that the laser pointer is correct at each end of track. Meaning it is the same distance "away" from the track at each end, in all directions. Now the next step is to mount the web cam on the "slead" on the current axis. The cam should be lined up so that the laser beam shins in the center of the web cam. (this is of course not an absolute)
Now what you get wen you look at your computer is a picture of a red dot.(the laser)
And now here is the part where i can no longer do anything sins i know ninkinpoop about programing. Now the idea is that when the slead moves along the track. If the "slead" is out of alignement the red dot wuld move on the screen. We should then have a script or program, that counts the number of pixcels the dot moves and then compensates. Sins the laser is 100% straight in all directions if it moves on the screen. The track must be out of alignment.
This would also help compensate for bending due to temperature etc. Causing an extreamly accurate machine.
This could be applied to all axis. And one could run the machine trugh the axis recording how the dot moves to make a referense. So the machine know prehand where to compensate.
But i can see two possible problems.
- Resolution on camera.
- Expansion of laser beam.