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List of all G-Code Commands Cura (Marlin Flavor) will use when slicing?
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· List of all G-Code Commands Cura (Marlin Flavor) will use when slicing?
STL files contain only triangles. No curves. So when a slicer slices a layer it finds the intersection of a plane with these triangles and ends up with a lot of lines. No curves. So cura creates no curves. No splines. So good news for you I guess.
I have completely rewritten the path planner for redeem (open source motion controller - runs on beagle bone black) so I'm very familiar with these. I've also looked at repetier host (open source - arduino hardware) and Marlin (open source - also arduino). I'm familiar with all these controllers.
One key thing is understanding the concept of what ALL of these path planners call "jerk" but is not jerk. It's "maximum instantaneous change in magnitude of motion". It's in mm/sec (or meters/sec in redeem). This sets the max junction speed. So for example if you are making tiny angle changes while printing a circle you can pass through the junctions (point at the end of each G0 or G1) at a high speed - maybe 100mm/sec. But if there is a 90 degree corner you have to slow down to 14mm/sec at the junction (assuming jerk is 20mm/sec). This is because if the head is moving 14mm in and out of the junction the change is the hypotenous or sqrt(14^2+14^2)=20
Another key concept is the "backwards planner". The arduino can only plan about 16 moves ahead (beagle bone black can do about 256 moves ahead). So you have to be able to stop. If you were moving at 300mm/sec on the final move which is say only 1mm long and then you stop, you will have a problem (skipped steps). So instead the planner makes sure you can always stop with the known next 16 steps (or so - depends how many steps are loaded into the planner at any given moment).
Posted
· List of all G-Code Commands Cura (Marlin Flavor) will use when slicing?
Thanks for the information! Also the clarification on jerk because I always assumed it was the mathematical definition of jerk and had no idea it was something entirely different! That also makes sense that its only linear commands because of your explanation of triangles which I definitely overlooked. This is all very intriguing info regarding the planner which I will definitely have to do more research into. Again, thanks for the knowledgeable info and insights.
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Cura 5.7 is here and it brings a handy new workflow improvement when using Thingiverse and Cura together, as well as additional capabilities for Method series printers, and a powerful way of sharing print settings using new printer-agnostic project files! Read on to find out about all of these improvements and more.
S-Line Firmware 8.3.0 was released Nov. 20th on the "Latest" firmware branch.
(Sorry, was out of office when this released)
This update is for...
All UltiMaker S series
New features
Temperature status. During print preparation, the temperatures of the print cores and build plate will be shown on the display. This gives a better indication of the progress and remaining wait time. Save log files in paused state. It is now possible to save the printer's log files to USB if the currently active print job is paused. Previously, the Dump logs to USB option was only enabled if the printer was in idle state. Confirm print removal via Digital Factory. If the printer is connected to the Digital Factory, it is now possible to confirm the removal of a previous print job via the Digital Factory interface. This is useful in situations where the build plate is clear, but the operator forgot to select Confirm removal on the printer’s display. Visit this page for more information about this feature.
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gr5 2,167
STL files contain only triangles. No curves. So when a slicer slices a layer it finds the intersection of a plane with these triangles and ends up with a lot of lines. No curves. So cura creates no curves. No splines. So good news for you I guess.
I have completely rewritten the path planner for redeem (open source motion controller - runs on beagle bone black) so I'm very familiar with these. I've also looked at repetier host (open source - arduino hardware) and Marlin (open source - also arduino). I'm familiar with all these controllers.
One key thing is understanding the concept of what ALL of these path planners call "jerk" but is not jerk. It's "maximum instantaneous change in magnitude of motion". It's in mm/sec (or meters/sec in redeem). This sets the max junction speed. So for example if you are making tiny angle changes while printing a circle you can pass through the junctions (point at the end of each G0 or G1) at a high speed - maybe 100mm/sec. But if there is a 90 degree corner you have to slow down to 14mm/sec at the junction (assuming jerk is 20mm/sec). This is because if the head is moving 14mm in and out of the junction the change is the hypotenous or sqrt(14^2+14^2)=20
Another key concept is the "backwards planner". The arduino can only plan about 16 moves ahead (beagle bone black can do about 256 moves ahead). So you have to be able to stop. If you were moving at 300mm/sec on the final move which is say only 1mm long and then you stop, you will have a problem (skipped steps). So instead the planner makes sure you can always stop with the known next 16 steps (or so - depends how many steps are loaded into the planner at any given moment).
Let me know if you have any questions.
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tcoons 0
Thanks for the information! Also the clarification on jerk because I always assumed it was the mathematical definition of jerk and had no idea it was something entirely different! That also makes sense that its only linear commands because of your explanation of triangles which I definitely overlooked. This is all very intriguing info regarding the planner which I will definitely have to do more research into. Again, thanks for the knowledgeable info and insights.
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