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Firmware2/Marlin/example_configurations/K8200
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AnHardt 7188ce0ad6 double bump probing as a feature 
Why double touch probing is not a good thing.

It's widely believed we can get better __probing__ results when using a double touch when probing.

Let's compare to double touch __homing__.
Or better let's begin with single touch __homing__.
We home to find out out position, so our position is unknown.
To find the endstop we have to move into the direction of the endstop.
The maximum way we have to move is a bit longer than the axis length.
When we arrive at the endstop - when it triggers, the stepper pulses are stopped immediately.
It's a sudden stop. No smooth deacceleration is possible.
Depending on the speed and the moving mass we lose steps here.
Only if we approached slow enough (below jerk speed?) we will not lose steps.

Moving a complete axis length, that slow, takes for ever.
To speed up homing, we now make the first approach faster, get a guess about our position,
back up a bit and make a second slower approach to get a exact result without losing steps.

What we do in double touch probing is the same. But the difference here is:
a. we already know where we are
b. if the first approach is to fast we will lose steps here to.
But this time there is no second approach to set the position to 0. We are measuring only.
The lost steps are permanent until we home the next time.

So if you experienced permanently rising values in M48 you now know why. (Too fast, suddenly stopped, first approach)

What can we do to improve probing?
We can use the information about our current position.
We can make a really fast, but deaccelerated, move to a place we know it is a bit before the trigger point.
And then move the rest of the way really slow.
2016-07-30 03:00:49 +02:00
..
Configuration_adv.h Unify config in a single include without nested includes 2016-07-25 23:04:19 -07:00
Configuration.h double bump probing as a feature 2016-07-30 03:00:49 +02:00
README.md readme.md -> README.md 2016-07-03 22:15:24 +01:00

README.md

Example Configuration for Vellemann K8200

  • Configuration files for Vellemann K8200 (with VM8201 - LCD Option for K8200)

  • K8200 is a 3Drag clone - configuration should work with 3Drag http://reprap.org/wiki/3drag, too. Please report.

  • updated manually with parameters from genuine Vellemann Firmware "firmware_k8200_marlinv2" based on the recent development branch

  • VM8201 uses "DISPLAY_CHARSET_HD44870_JAPAN" and "ULTIMAKERCONTROLLER"

  • german (de) translation with umlaut is supported now - thanks to @AnHardt for the great hardware based umlaut support

I @CONSULitAS tested the changes on my K8200 with 20x4-LCD and Arduino 1.6.1 for Windows (SD library added to IDE manually) - everything works well.

Source for genuine Vellemann Firmware