Is it possible to do simulatneous, but independent coordinated movement of 2 groups of axis?

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carboncymbal
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Is it possible to do simulatneous, but independent coordinated movement of 2 groups of axis?

Post by carboncymbal »

I'm considering a building a CNC router that uses a single gantry with 2 X axis oriented axis, each driving an independent Z axis oriented axis. Basically imagine a traditional CNC router with 2 fully independent spindles with independent movement on X and Z. The application is a CNC machine where fast cycle time (say, 15-20 seconds) per part is desired, but using up to 4 tools. This would allow for each spindle to independently conduct a tool change while the other is cutting. It isn't clear to me how this would be programmed (or if it is even possible). The machine would need to run X,Y,Z in coordinated motion while Y2,Z2 is engaged in coordinated movement to conduct the tool change.

Thoughts?


cncsnw
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Re: Is it possible to do simulatneous, but independent coordinated movement of 2 groups of axis?

Post by cncsnw »

No.

If you build your tool changes with pneumatic slides for in/out and up/down motion, so that no servo movement is required during a tool change, then there is a slight possibility you can do what you want. However, even then, it would be a long road, because it would depend on axis pairing configurations that are not supported by the Acorn Wizard.


suntravel
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Re: Is it possible to do simulatneous, but independent coordinated movement of 2 groups of axis?

Post by suntravel »

Acorn 6 is 4+2 axes simultaneous, with ultimate plus 6 axes simultaneous.

Within this limits you can do what you want, if you are good with g-code, PLC and probably PP writing for your CAM :)

Uwe


cncsnw
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Re: Is it possible to do simulatneous, but independent coordinated movement of 2 groups of axis?

Post by cncsnw »

... but all servo axis movement during a CNC program cycle has to be controlled with CNC codes, which run in sequence in a single processing thread. Therefore you cannot have three or four servo axes machining a part, while at the same time two other servo axes do their own tool changer movements.

To accomplish this type of operation through creative G code or CAM postprocessor programming would require that you pick out, of the part geometry you are machining, which cutting move(s) will be combined with which tool-change moves. And of course, cutting motion would need to pause while the drawbar opens and closes.

All that is theoretically possible, but extremely inconvenient.


suntravel
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Re: Is it possible to do simulatneous, but independent coordinated movement of 2 groups of axis?

Post by suntravel »

Yes, sure, this is better for 2 synchronized CNC systems.

But on the other hand a Fanuc Robodrill is with 0.7 s chip to chip time in a tool change.

On a router I would try to clamp as much parts as possible to reduce tool change time per part or go with a drilling block...

Uwe


carboncymbal
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Re: Is it possible to do simulatneous, but independent coordinated movement of 2 groups of axis?

Post by carboncymbal »

Thanks for the suggestion all, the feedback is what I expected. It would be cool if Centroid had a method of running parallel G-code, but I imagine that is an extremely niche and rarely justified use. Other applications may lathes with multiple turrets or applications where the additional axis are used to control automated part loading.

My current plan uses 2 spindles, 1 ATC and 1 manual. In reality most of my production programs only require 2 tools, For extremely short cycle times (say 5 seconds) I'll actually have both spindles run at target RPM for the entire length of the program. My chip to chip time should beat a brother speedio or fanuc robodrill ;)

Thanks again for the responses.


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