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Yes this sentence in particular:

In a blend that is an exact reversal, this causes the total axis acceleration to equal the INI file MAX_ACCELERATION.

Seems to allude to coordinated motion of more than one axis but why is that 'an exact reversal'?


This behavior has been discussed several times but I don't think anybody had an explanation for it:

forum.linuxcnc.org/38-general-linuxcnc-q...long?start=10#210458
forum.linuxcnc.org/49-basic-configuratio...n-config-file#279913

This one is particularly interesting:
forum.linuxcnc.org/49-basic-configuratio...eration-value#128957

I don't understand the content of this part, why use half of the acceleration? Is there any article that can explain this problem in detail?

Important User Concepts (linuxcnc.org)  1.4. Planning MovesMake sure moves are long enough to suit your machine/material. Principally because of the rule that the machine will never move at such a speed that it cannot come to a complete stop at the end of the current movement, there is a minimum movement length that will allow the machine to keep up a requested feed rate with a given acceleration setting.The acceleration and deceleration phase each use half the INI file MAX_ACCELERATION. In a blend that is an exact reversal, this causes the total axis acceleration to equal the INI file MAX_ACCELERATION. In other cases, the actual machine acceleration is somewhat less than the INI file acceleration.To keep up the feed rate, the move must be longer than the distance it takes to accelerate from 0 to the desired feed rate and then stop again. Using A as 1/2 the INI file MAX_ACCELERATION and F as the feed rate in units per second, the acceleration time is ta = F/A and the acceleration distance is da = F*ta/2. The deceleration time and distance are the same, making the critical distance d = da + dd = 2 * da = F2/A.For example, for a feed rate of 1 inch per second and an acceleration of 10 inches/sec2, the critical distance is 12/10 = 1/10 = 0.1 inches.For a feed rate of 0.5 inch per second, the critical distance is 52/100 = 25/100 = 0.025 inches.

OOps, my appologies.
I just realized that I also have a 2.10 rip installation on that machine. So you are probably right and the deb installation does not come with the c source files. Kind of makes sense I guess.

Aciera wrote:

just checked on 2.9.2 installed through the package manager on a LMDE system , 'halcmd.h' is located in '~/linuxcnc/src/hal/utils'
 

 
Sorry and ~/ means for xxx/home/linuxcnc or /linuxcnc ... because I install from package manager too .... 5 month ago ... than start now to check again my new project and not find that folders .... all linuxcnc is on ~/lib, ~/usr/share, ~/bin, ~/etc .... there are not folder named ~/linuxcnc .....

 

Try:

just checked on 2.9.2 installed through the package manager on a LMDE system , 'halcmd.h' is located in '~/linuxcnc/src/hal/utils'

see below

so try to install a new master .rip install .... but obtain these at the end.


Any how needs to install libreadline-dev

what is these??


regards

Hello,
Has there been any progress on the theme?

I found that the G64 will be slower than G61, twice or even more slower, in the stage of acceleration and deceleration.

Yes, I can understand that the overall speed will be slower, and he needs to reduce the speed to reduce excessive angle.
However, what I noticed was that his acceleration became slower.
Pay attention to it, weird things…, when use G61 or G61.1, I observe the servo waveform, accelerate the time meets the expectations, such as I can get the acceleration time curve of 100MS according to the acceleration I set over G61
But when I use G64, my acceleration time has slowed down, which is nearly twice the relationship, that is, I continue to observe the waveform and get a 200MS acceleration curve.

Regarding the formula for Theta(1,0):

I still don't fully understand the first formula, the short one at the top.
I think its calculating the "angle start" parameter for the z component.
 

This calculates the tangent angle (in the XZ plane) in the starting point (s0) of the clothoid on the first trajectory segment after rotating and translating the space corner so that the normal vector of the corner coincides with the z-axis (as shown in Fig 6 ).
If the corner is planar then the expression inside the bracket is zero and Theta(1,0) is zero (ie the tangent is horizontal).

I haven't yet been able to make up my mind if this method can also work for arc-helix corners.

[edit]
Well, I've given it a fair bit of thought and I cannot see a reason why it shouldn't work with helical segments.

The acceleration of X/Y I use, such as 500

SO search today with NEMO for example halcmd.h .... and find only "halcmd.1.gz" ..... from long time I use only rip installation than if work I install it .... so never investigate where that file is located in a normal installatio ... maibe there are not because it become .so or .a that system not copy these file in some locations ..... but I search for a confirmation ...

thanks

on the topic of my atc. seems a good reason to try and text the lichuan ethercat servos. 40mm 50 or 100w model.

Does ethercat works WITH the mesa card already there? as in, can i use both? or do i need to switch to all ethercat?

rodw wrote:

 

I had to get the wall mount version as I was squeezing it into an existing HMI enclosure that was too small to take one like yours. I looked back. 12 nobths ago, I paid USD $157 plus shipping to Australia so all up it was just under AUD $500



 

It'd be great if one day you could quote a post with a quote and not have the editor go haywire

That's exactly what mine "cost" but you got killed on shipping. I bought mine from the Chinese manufacturer on Alibaba. I'd probably do alot better if I ordered several