CoreXYUV with dynamic load\force balancing.
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@fma said in CoreXYUV with dynamic load\force balancing.:
You need to think in term of acceleration, not distance. I think it is equivalent, but I didn't do the maths (you just need to do X/Y projections and compare).
Anyway, your setup is really impressive! And if it work, don't fix it
It's the mass I was wondering about. As it stands, the mass in X is 2340 gms. The additional mass in Y is 1866 gms. So the total mass in Y is 4206 gms. To compensate for the force exerted in X, the front and back weights in that diagram would have to add up to 2340 gms. To compensate for the mass in Y, the two side weights would have to add up to 4260 gms. So for a 45 degree move of the CoreXYUV gantries, the force would some sort of vector of 4260 gms (maybe) x acceleration. But all 4 side weights would move toward the opposite corner, meaning that the total compensating mass would be 2340 plus 4260 = 6546 gms. So if the acceleration for those weights was the same (which I think it would need to be), then the compensating force would be much higher than needed. (I think). But there are complications of vectors and different move distances which my ageing brain can't be bothered to look into.
Anyway, what I have come up with works, so that's good enough for me.
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As promised. For anyone who's interested, you can read the waffle here https://somei3deas.wordpress.com/2018/10/04/dynamic-force-cancellationload-balancing/
and you can watch the video here https://www.youtube.com/watch?v=HS7LvcBowCA
The video is fairly well annotated so should work "stand alone" if you don't want to read the waffle. Or if you want to do both, there is a link to the video at the end of the blog post.
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First, you video of gantry assembling is very cool
And the result is amazing! Well done.
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Wow that worked out great. Have you noticed a difference in surface finish? ie, ringing?
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That is wonderful............. speechless!
Well.... Five extruders, Diamond 5x hot end.... active dampening..... Some 500mm/s printing tests soon?
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https://www.youtube.com/watch?v=dd5WqmWIRzw came this in mind
But these buildings dampeners are passive -
@brunofporto Except Deckingmans printer is only slightly less massive than that 700 ton ball.
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@brunofporto @Phaedrux Oh trust me, I looked hard at using a tuned mass damper - https://forum.duet3d.com/topic/6677/corexyuvwa before I went down this route.
Although that one is 700 tons, it's a very small mass compared to the mass of the building. The main reason it wouldn't work in this situation is because they have to be tuned to the resonant frequency of the structure, and in this case rather than a single frequency, there is a very wide range of frequencies due to the nature of print (and non-print) moves.
A pity because it would have been a very elegant solution (and probably a damned site cheaper).
@Phaedrux - that's another 12 sets of Delrin wheel kits I've used, bringing the total up to 52 on this printer.
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@brunofporto said in CoreXYUV with dynamic load\force balancing.:
........................Some 500mm/s printing tests soon?That's probably pushing things a bit but we'll see........
Hot end pressure is the killer and there is only so much that compensation can do about that. But, I do have a 0.9mm diameter nozzle so...........
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@deckingman I think your wheel budget might just exceed my whole printer budget.
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@brunofporto Actually, I had already used all 10 of the Duet plus Duex5 drivers and didn't much fancy the complexity of adding two external ones. So at the moment it's either 5 extruders, or 3 extruders with dynamic force cancelling but not 5 extruders and dynamic force cancelling together. That will have to wait for gen 3 Duet.
But changing from one configuration to another is simply a matter of swapping two motor connectors on the Duex5 and uploading the appropriate configuration files - about 2 minutes max.
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@phaedrux said in CoreXYUV with dynamic load\force balancing.:
@deckingman I think your wheel budget might just exceed my whole printer budget.
Gives me nightmares just thinking about it...........
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This is great and crazy altogether! I seriously love it! If I had a CoreXY, I guess I would just copy this build because it's so cool - totally independent of necessity.
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@deckingman said in CoreXYUV with dynamic load\force balancing.:
Gives me nightmares just thinking about it...........
We have a saying around here that you should NEVER sum up hobby and/or pleasure budgets
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Great work Ian. I might have an old RAMPs board + some stepsticks lying about that can be used to get you those two other drivers so you can have 5 colour + dynamic load balancing.
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@t3p3tony said in CoreXYUV with dynamic load\force balancing.:
Great work Ian. I might have an old RAMPs board + some stepsticks lying about that can be used to get you those two other drivers so you can have 5 colour + dynamic load balancing.
Thanks Tony - that's kind of you. Hold fire for now though. I've a lot other stuff in hand at the moment and 5 colour plus dynamic force balancing isn't high priority just now (given that I can easily have either\or).
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@deckingman silly you, we are watching.
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@deckingman said in CoreXYUV with dynamic load\force balancing.:
@brunofporto Actually, I had already used all 10 of the Duet plus Duex5 drivers and didn't much fancy the complexity of adding two external ones. So at the moment it's either 5 extruders, or 3 extruders with dynamic force cancelling but not 5 extruders and dynamic force cancelling together. That will have to wait for gen 3 Duet.
But changing from one configuration to another is simply a matter of swapping two motor connectors on the Duex5 and uploading the appropriate configuration files - about 2 minutes max.
It's easy to use motors 9 and 10 on the duet2 itself without expansion. They are present on the (unused) LCD connector and it's just a matter of using two external breakout boards. Like on this image:
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@token47 Yes I know, - and if you look a couple of posts up, Tony has already offered to supply the hardware. But it's still a fair amount of wiring, and some configuration changes. Both of which would have to be changed yet again when gen 3 Duet comes out. As and when that happens, I'll be gutting out all the wiring so I don't see much point in adding more at this moment in time.
As I have no immediate need to print 5 colours plus use the dynamic force balancing gantry, it's not worth the effort at this time. If I desperately need to print something using 5 colours, all I need do is swap two stepper motor connectors and upload the original config.g and homing files - about 2 minutes max (oh and print it slow by my standards which is still fast by most peoples
)BTW, starting as we do with drive number 0, it would be drivers 10 and 11, not 9 and 10, as drives 0 to 4 are on the main board and 5 to 9 on the Duex5.
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@token47 said in CoreXYUV with dynamic load\force balancing.:
@deckingman silly you, we are watching.
Huh??? Has someone crept in to my study and installed a hidden camera that I don't know about? Have the GRU started to take an interest in me? Is that white Transit van parked down the road not what it seems?
