I wanted to even ask which models have the greatest rigidity of robots?whether small kr60 or maybe those big titan1000 ?
How to improve the accuracy of cutting
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Martin84 -
December 5, 2016 at 1:46 PM -
Thread is marked as Resolved.
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The smaller robots tend to have better rigidity against the effects of gravity, due to having less mass, and that mass having less lever arm to work over.
But the larger robots have better rigidity to external forces, like the recoil from milling forces. Where exactly the ideal tradeoff occurs is... complex, and depends a great deal upon the details of the specific application.
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Hi , sorry interrupting the conversation.
But i am doing laser cutting , kr120 r 3900 k ultra c, power source- IPG photonics, YLS-3000.
i don,t know whenever my robot changes it,s direction , it tends to have a jerk , which makes my cutting quality poor, can anybody suggest something to overcome this issue, i tried hell lot of things.
sheet thickness range - 1.2 mm-2 mm ,spangled galvanized.
my geometry of cutting is rectangle and square.thanks
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It will help if you could post a video to show the problem and also some sample code - at least the head of the file with some lines ?
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Ah geez, I've been avoiding cutting things with robots as of late for these reasons entirely.
I'm with TygerDawg & SkyeFire as I believe we have all suffered similarly at some point or another. Cutting small circles with a 6-axis robot is not trivial and there's a limit to at which point the machine shines more for rough-cuts.The circles drawn earlier in this thread show exactly the points where a joint is changing direction and either show backlash or 'floating' as one joint doesn't move as much as others.
Some things to try at first blush which have already been mentioned
- Smaller robots do better to cut smaller holes (ignoring cutting forces and just considering geometry)
- Make sure your tool mass load settings are accurately set! this makes a huge difference as the robot will be attempting to compensate for this. Cutting forces withstanding.
- cut slower, reduce acceleration and deceleration (VEl.CP, ACC.CP)
- linearize circle movements and try very small increments of linearization (small chordal deviation) ie: More points = Better, but motion 'smoothness' can be affected as the speed goes up
- Cut on a different plane to use more of one axis vs. another (ie: Axis 1 doing most of the 'circular' path will be the least accurate)
- C_VEL & C_DIS make a huge difference in how points are processed, try values for those but my starting point for C_DIS was 01.mm-1mm.
-- you CAN pre-load axis 1 by mounting the robot on an angle and this can have desirable effects on one side of the cutting area, but the effect isn't a magic button and now you have to calibrate your work objects with this angle in mind (buy a decent digital protractor/level before you even start)
sudeep, a KR120 is a big robot, and not having HA calibration on it puts you at a bit of a disadvantage (assuming it's not HA). I understand the frustration - what kind of deflection from change of direction are we talking about? There is a ceiling with what robots can do - are you programming manually or from CAD/CAM? CAD/CAM can give you some more options to play with in how it generates the points.
I want to make this one work for you
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