Probe deceleration path #171
Description
Is it possible to add an option of probe hard stop (as soon as the probe is triggered)? And to add to $$ one more value (say, named as "hard probe stop feed") to define a maximum probe feed applicable for hard probe stop?
This option would be useful for some precise operations, for instance, for the backlash measurement or for the tool positioning.
I am asking for this option because the real probe deceleration path is significantly longer than the theoretical one. The results which I got on my machine are shown at the graph below.
The measurements have been made for various probe feeds using G38.2 code.
Green points show the theoretical length of deceleration path Lt=0.5*V^2/a, where V is the probe feed, and a denotes the acceleration.
Blue stars show the measured length of deceleration path Lm=Mpos-PRBpos, where Mpos is the machine position after the probe is stopped, and PRBpos is the probe position when the probe is triggered.
For example, look at the first graph point (feed=10mm/min). Its theoretical value is 0.46 mcm that is less than one-half of my machine distance_per_pulse. In this case the probe has to be stopped immediately without any pulse generation. But the real probe deceleration path is 3.5 mcm, so about 3 pulses were generated.
Well, the perfect solution of this issue is to fix the probe algorithm at the level of planner. But I think it is much more time-consuming than to add a hard stop option.