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Dh parameters= real positon/ angles
Vismach model = not build by dh paramters.

Or what do you mean?

Yes.

But the real problem is that you are getting ahead of yourself. There is ZERO point in hooking up your robot to linuxcnc before you have a clear understanding of what those modified DH parameters actually mean.

Step 1: Take the drawings of your puma, draw a kinematic model and derive a set of DH parameters.

Step 2: Take a six-axis SIM config (without hooking up ANY hardware) that uses genserkins and verify that the World coordinates calculated for simple poses are what you expect.

There is absolutely no point in either hooking up your robot or building a vismach model before Step 2 has been completed successfully.

Please. Can someone tell me how to update debian bookworm. I am getting this error
dpkg: error processing package linux- image-6.1.0-40-rt-amd64 ( --remove) :installed linux-image-6.1.0-40-rt-amd64 package post removal script subprocess returned error exit status 1
dpkg: too many errors, stopping
Thanks
 

Grandixximo just wanted to ask have you done any work to fix the lookahead on multiaxis movements.  on the old trajectory planner the lookahead reverts to slower movement (almost no lookahead) when using a 4th axis.  or any extra axis after 3 axis  it's a real pain when machining

i have been playing with scurve sim but can't work out if it fixes the issue yet. so thought i would ask a question about it here

cheers

Chris there is a bug with the index enable stuff i think when summing the PID loops like this. I forget exactly why i connected both encoder index pulses to index enable

i read i think earlier in this thread that you can connect both encoders to index enable and also connect them with a physical wire so the first index to fire triggers the homing. but i couldn't get it to work. rereading my post it sounds like i just messed this up but i really do think there is a bug. I could test if you want to go through with me and prove the issue. we have messaged off forum on messenger before..

so i tried just one PID loop with the velocity input coming from the encoder and the position input coming from the scale. and that homed to index enable fine but the tuning was really rough. i couldn't believe how bad it was. it was like there was a stuffed bearing on the ballscrew. and the axis kept bounching back and forth around the 0.1mm backlash which was unusable. and after i had just tested the other way with a smooth as silk axis that always stopped perfectly within 0.002mm I wasn't going back I talked about the mesa index enable issue with PCW a bit but i ran out of time to fully prove it was a bug. But i definitely think that having the 2 separate PID loops breaks the index enable logic.

anyway after all that i read somewhere on the forum that someone else had the same issue for some reason and the really inelegant solution is to run the home switch through classic ladder and have it trigger on the home switch first and then look for the change in homing state and on the next state when the encoder is searching for index pulse use classic ladder to feed it the encoder physical index pulse from rotary motor encoder on end of ballscrew. this means that you have to home that last little bit extra slow as it can miss the pulse. and it is not that best. But in saying that i haven't had it miss the pulse yet and it's not that much slower to home.

But i would like to fix this as this is the last annoyance that if it was fixed i would probably go crazy and put scales all over my machines lol

So Chris your classic ladder is still getting used all the time by people keep up the good work.

cheers andrew

Hey Tuxcnc

just wanted to message back here and explain some of the reasons for the tool wear remap t0101 etc

On almost all commerical cnc controllers (fagor fanuc mazak misubishi semiens heidenhain (also Pathpilot which is sort of a commerical version of linuxcnc)  you can change a offset to account for the tool wearing or machining cutting slightly the wrong size over time or part to part.  usually you have a option where you can just change the value by 0.05 or something and it changes the size the machine cuts a bit.  if you only use T1 m6 g43 then you have to adjust the actual tool geometry offset.  which if you have boring bars and also turning tools can be like 300mm different.  if you muck up your maths here or make a typo.  i been there and done it then the next time you run the machine it crashes.  and then also if you have a unskilled operator on the machine it's even worse.  anyway all these issues are good reasons to have some way to make only small changes to the tool size.  the T0101 remap is not the best way i could be quite happy with just t1m6 also if there is a good way to include wear offsets but i haven't seen one so i use the remap that chris morley made years ago.  I have a production lathe that would have made 50,000 parts now and wear offsets are essential in my opinion.  

I can probably change the cycles to output only T1m6g43 once i am finished if you want it.  though your solution you showed seems to work.

cheers becksvill

Ah i think i understand what you mean.

The model stays in a different position as the seted dh paramters ? Because i rotate the hand axis ( all 3) and the main tower.

Dh parameters= real positon/ angles
Vismach model = not build by dh paramters.

Or what do you mean?

The dh parameters i set are the parameters i get from right hand ruled cs. Possible i do it wrong. Because .. if i home over my sharpie marks the arm is in this position:

Joint 1 0 ( about 140 +- to the mechanical limits)
Joint 2 0 (90 deg to tower.. means parallel to base)
Joint 3 0 ( 90 deg to joint 2... means parallel to tower)
Joint 4 0 ( mid position +- 320)
Joint 5 0 ( mid position +-125)up and down same direction as joint 2 and 3
Joint 6 0 (mid position +- 280) left right same as joint 4

The values of A and D i get from the drawing
The Alphas i get from right hand rule cs.. and the signs for the A and D values i get with the alpha stuff.

And the angles after homing i checked with a digital pritractor... and the scales i checked with 90 deg moves looking to the digital protractor.

Hi grandixximo,
We really appreciate your dedication to solve the jerk limiting trajectory planner issue.
Can you share the update on any git repo to get wider community feedback started?
Looking for to testing the new fixes.

-automata

Because I'm busy with work, I'll do testing when I have time.

Not me.

I was able to reproduce this in a virtualbox test-installation. After entering a wrong name/passw  i was locked out. This solution gave me access again. And after that procedure, even entering the password wrong once, did'nt lock me out. Just enter correct password and login.


after this popup

 


Press the e key to open the boot parameter editor
    

Who creates the RPi4/5 image here:

linuxcnc.org/downloads/

Good thought but its a laptop an older Dell no video card other than built in Video
don't know if it matters but password login error screen says... "your password is incorrect try again" cancel / log in boxes ...... nothing else and the same thing over and over when entering the password. I was super careful in the setup of these areas during setup
Tks

Hi Cmorley

I've tested it some more, and I don't need to touch "def external_offset_state_changed(self, data):"; it works fine without any changes. I don't know why I had the problem before, but the stop button is still a problem.
To stop the spindle, I have to press stop a second time.

5280 wrote:

cant get past name and password screen yet.
 

If you see GRUB but after only blank screen, this may be graphic card issue. In this case try apply nomodeset kernel parameter at grub screen (there are many tutorials on internet). 

Thanks 4 the info
but I have not been able to get to the terminal yet
cant get past name and password screen yet.
have done 4-5 fresh install of the OS. they all hang up at the same place name and password screen
Thanks