Klipper/Kinematics — Ukrainian @ Hosted Weblate: Pressure advance

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	With delta kinematics it is possible for a move that is accelerating in cartesian space to require an acceleration on a particular stepper motor greater than the move's acceleration. This can occur when a stepper arm is more horizontal than vertical and the line of movement passes near that stepper's tower. Although these moves could require a stepper motor acceleration greater than the printer's maximum configured move acceleration, the effective mass moved by that stepper would be smaller. Thus the higher stepper acceleration does not result in significantly higher stepper torque and it is therefore considered harmless.
	However, to avoid extreme cases, Klipper enforces a maximum ceiling on stepper acceleration of three times the printer's configured maximum move acceleration. (Similarly, the maximum velocity of the stepper is limited to three times the maximum move velocity.) In order to enforce this limit, moves at the extreme edge of the build envelope (where a stepper arm may be nearly horizontal) will have a lower maximum acceleration and velocity.
	Extruder kinematics
	Klipper implements extruder motion in its own kinematic class. Since the timing and speed of each print head movement is fully known for each move, it's possible to calculate the step times for the extruder independently from the step time calculations of the print head movement.
	Basic extruder movement is simple to calculate. The step time generation uses the same formulas that cartesian robots use:
	Pressure advance	Pressure advance
	Experimentation has shown that it's possible to improve the modeling of the extruder beyond the basic extruder formula. In the ideal case, as an extrusion move progresses, the same volume of filament should be deposited at each point along the move and there should be no volume extruded after the move. Unfortunately, it's common to find that the basic extrusion formulas cause too little filament to exit the extruder at the start of extrusion moves and for excess filament to extrude after extrusion ends. This is often referred to as "ooze".
	![ooze](img/ooze.svg.png)
	The "pressure advance" system attempts to account for this by using a different model for the extruder. Instead of naively believing that each mm^3 of filament fed into the extruder will result in that amount of mm^3 immediately exiting the extruder, it uses a model based on pressure. Pressure increases when filament is pushed into the extruder (as in [Hooke's law](https://en.wikipedia.org/wiki/Hooke%27s_law)) and the pressure necessary to extrude is dominated by the flow rate through the nozzle orifice (as in [Poiseuille's law](https://en.wikipedia.org/wiki/Poiseuille_law)). The key idea is that the relationship between filament, pressure, and flow rate can be modeled using a linear coefficient:
	See the [pressure advance](Pressure_Advance.md) document for information on how to find this pressure advance coefficient.
	The basic pressure advance formula can cause the extruder motor to make sudden velocity changes. Klipper implements "smoothing" of the extruder movement to avoid this.

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Pressure advance	Pressure advance	Klipper

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Screenshot 2021-06-21 at 11-50-15 KevinOConnor klipper-translations

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docs/locales/uk/LC_MESSAGES/Kinematics.po, string 45