Welcome, Guest. Please login or register.
Did you miss your activation email?
July 28, 2014, 09:34:20 PM

Login with username, password and session length
Search:     Advanced search
* Home Help Search Calendar Links Login Register
+  Machsupport Forum
|-+  Third party software and hardware support forums.
| |-+  Galil (Moderators: smurph, kcrouch)
| | |-+  Mitsubishi J2S-40A and Galil DMC-2183 with ICM-20105
Pages: 1 2 »   Go Down
Print
Author Topic: Mitsubishi J2S-40A and Galil DMC-2183 with ICM-20105  (Read 2217 times)
0 Members and 1 Guest are viewing this topic.
heathmanc
Holding

Offline Offline

Posts: 1


View Profile
« on: April 14, 2012, 12:57:08 AM »

First time trying to set this up and not having a lot of luck.  I want to use torque mode.  I have the SON from the ICM-20105 set up sinking low enable.  This all works.  When testing the amp without the controller, upon power on, the amp gives a ready signal, but the servo is not locked, but when put in test mode, it locks up and I can jog.  There are RS1 and RS2 switch inputs on the amp (forward rotation start and reverse rotation start).  If I connect one of those to SG, then the motor locks.  I am inputting the motor command and ground from the galil to the TC-LG terminals.  If I don't connect the RS1 or RS2 and give an OF 5, I get 5v displayed on the mitsubishi.  If I connect RS1 or RS2, I get a 0V displayed on the amp..  Just looking for a place to start with all of this...
« Last Edit: April 14, 2012, 12:59:45 AM by heathmanc » Logged
battwell
Active Member

Offline Offline

Posts: 123


View Profile WWW
« Reply #1 on: August 24, 2012, 02:29:05 PM »

did you get this working? i have mr-j2s working with galil in torque mode
Logged

if its not broken yet, fit more gadgets!
coolfox
Active Member

Offline Offline

Posts: 40




View Profile
« Reply #2 on: November 18, 2013, 06:33:18 AM »

battwell can you please comment is this path with Galil and Mitsu worth going? I'm using this J2 series Mitsu for a while now but in position control mode with step direction. All work but axis coordination in 3D milling not good. I was wonder if Galil will fix this as it has ability of coordinated multi-axis movements were it read encoders and correct the path all the time?
I don't fully understand how much control in this layout placed on Galil if there only servo control separate axis or with element of coordinated movement.
In my opinion this is Mash downside with servos luck of control loop on actual axis movement. Or I my misunderstand something?
Logged
smurph
Active Member

Offline Offline

Posts: 564


"That there... that's an RV."


View Profile
« Reply #3 on: November 21, 2013, 02:38:49 AM »

The Galil has the servo/PID (control) loop.  With the Mach/Galil combo, Mach is the HMI and trajectory planner.  The Galil does all of the real-time PID loop stuff.  The combination works really well. 
Logged
coolfox
Active Member

Offline Offline

Posts: 40




View Profile
« Reply #4 on: November 29, 2013, 04:04:10 AM »

lets rephrase. Ok. Mach does all the trajectory and Galil PID control for motors my question- does Mach trajectory planing adapt to Galil real time PID work in some form of feedback analysys and look ahead logic adaptation?
Mach send time/control point coordinates over ethernet to Galil?
Logged
coolfox
Active Member

Offline Offline

Posts: 40




View Profile
« Reply #5 on: November 29, 2013, 04:42:49 AM »

Another Great benefit of Galil controllers in ancillary encoder inputs with can be connected to linear encoder on linear the axis and rotary directly in the spindle, this setup will eliminate mechanical and drive errors.  
Is there anyone manage to implement this closed loop control function with Mach?
And how this configuration look?
Logged
smurph
Active Member

Offline Offline

Posts: 564


"That there... that's an RV."


View Profile
« Reply #6 on: November 29, 2013, 02:44:11 PM »

Mach does the trajectory planning once.  Say move X axis 20.0 units (G01 X20.0 F20).  Why would Mach ever have to re-plan that trajectory?  That part never changes!  The over all goal is to move the X axis 20.0 units.  The planner calculates the proper accel/slew/decel profile to get there and that is a constant!  I don't know why people get stuck on trajectories ever having to be re-planed.  This is NEVER the case no matter what control is being used.  Mach can send these trajectories to the Galil in a variety ways;  Linear Interpolation mode, Contour mode, and (in the future) position with velocity over time (PVT) mode on the newer controllers.

What I think people get confused with is what the PID loop is actually doing.  It is not controlling the planner or modifying it.  It is controlling the servo drive by looking at the following error.  If the drive is not able to follow the planned trajectory and the following error increases, the PID loop makes adjustments to the servo drive inputs (command velocity/torque) to correct that situation.

Mach feeds the Galil with a trajectory.  The Galil then does what it takes to follow that trajectory.  If the Galil can't make the servos follow the trajectory, then no re-planning is ever done.  Mach told the Galil to move X 20.0 units and it just didn't get it done.  Is this a reason to re-plan the trajectory?  No!  It is a symptom of an incorrectly tuned servo/control loop!  The Galil KP, KI, and KD parameters need to be tuned.

When Mach plans a trajectory to move the X axis 20.0 units, it is very much analogous to using the Galil PR command.  Say the encoder is 10000 counts per unit so PRX=200000 would be equivalent to the G code G01 X20.0.  If you issued that PRX=200000 command on the Galil terminal, the Galil would plan the trajectory and then execute it.  It will never re-plan that trajectory if the servos didn't hit the numbers.  It does not come back and issue an extra PRX=1000 if the servos ended up 1000 counts short.  What it does do is look at the following error and see that it is 1000 counts short of it's planned trajectory and then it increases the command voltage to the servo drive to get it there.  If the PID parameters are correct, then the goal will be obtained.

All of the features of the Galil still work when used with Mach.  You can still use the dual encoder feedback.  Why?  Because the loop is closed on the Galil.  Mach doesn't have to close the loop.  Mach will never close the servo/control loop on Windows because Windows is not a real-time operating system.  Mach depends on controllers like the Galil, Vital Systems DSPMC, and Mesa (future) to do this.  Closing the servo loop NEVER involves re-planning the trajectory.  Closing the loop is always about correcting the following error while executing the planned trajectory. 

I have run the dual encoder feedback on the Galil.  It does work but it has its limits.  Galil fully explains these limits.  And it should be used as a last resort!  It is always best to fix mechanical errors with hardware rather than fixing them in software.  Galil also offers special firmware that can map screw variances and account for backlash.

Steve
Logged
coolfox
Active Member

Offline Offline

Posts: 40




View Profile
« Reply #7 on: November 29, 2013, 06:30:55 PM »

Steve
Thanks for clearing air again.
Agree in single axis single Say move X axis 20.0 units (G01 X20.0 F20). trajectory need nothing but correct execution from servo and mechanics with is not simple ballscrew thermal and backlash compensation, with dynamic forses all mashine flex and bend under cutting and aceleration forces 50mk easy even for steady industrial mill ( hens idea of reading actual slide position with axilary encoder and live velocity to motor rotary encoder).
just for example G2 or G3 send to galil CR comand ?  In this case Galil coordinate ( plan) trajetory of two axis ?
Sorry for all this noncence just want to umderstand how this work better.
Ilia
Logged
smurph
Active Member

Offline Offline

Posts: 564


"That there... that's an RV."


View Profile
« Reply #8 on: November 29, 2013, 10:58:57 PM »

No, we don't use the Galil CR command.  Mach plans the trajectory for the circle and sends it down via LI or CD commands, depending on what the user has chosen to use in the Galil plugin (Linear Interpolation or Contour mode).  Whether it is a straight line with a single axis or a circle with multiple axes, it does not matter.  The same thing is happening.  The Galil gets the trajectory data from Mach and then the Galil is in charge of following it.  No matter what plans the trajectory, it NEVER gets planned more than once.  NEVER.  I don't know of any machine controller on the planet that does this.  Fanuc, Fidia, EMC, etc...  Why would they?  The trajectory is computed and then it has to be followed.  If the machine cannot follow the trajectory and it has to have the trajectory re-planned, that is a bit like having the tail wag the dog.  That is one messed up dog!  Smiley

Here is a sample of what we are sending to the Galil (A lathe in this case).  The moves are incremental and it is using Linear Interpolation in this example.  Mach plans the LI data points.  The BG S command tells the Galil to start executing the trajectory:

LM AC
VT 1.000
VD 30000000
VA 30000000
LI -170,,-57<11206
LI -341,,-114<22470
LI -204,,-68<13438
LI -1,,-1<88
BG S  
LE

If the movement is complete and the table is not at the correct position, then the PID parameters need to be looked at.  The real-time component in a servo motion system is used to look at the incoming position data and adjust the servo drive command inputs (via the PID filter) to maintain an acceptable following error.  The target positions and target velocities have not changed.  If the following error is too great, then the PID loop may specify more voltage on the command inputs of the drive.  (Stepping on the gas).  If it gets too aggressive, then the PID loop may specify less voltage on the command inputs of the drive.  (Stepping on the brakes).  

The car/driver analogy fits very well.  Say you plan your route to get to the hardware store.  This route includes a lot of starts and stops and some curves.  This route planning is what Mach does.  Accel to slew, slew (Speed limit), and decel to stop.  Turn right, accel to slew, slew, and decel to stop, etc...  You, as the driver of the car, are responsible for following the route.  You are the motion controller!  If you accell too much, you may get a speeding ticket.  Also, if you fail to decel, you make get a ticket for failing to stop.  You manage all of this by looking at the speedometer and visual judgements (encoders) and adjusting how much gas or brakes (PID loop) it takes to command the car.  This is the real-time component.  What happens if you hit the brakes too much and you don't reach the stop sign at the intersection?  Do you re-plan your route?  No.  Because the route has not changed.  The road has not gotten any longer and the target stop sign hasn't moved.  You just failed to command the car correctly.  In this case you need to go back to driving school (update your PID values).  Smiley

With the Mach/Galil combo, Mach is the HMI, G code interpreter, and trajectory planner.  The Galil controls the motion to follow that trajectory.  That system will make beautiful parts with high accuracy and repeatability if the machine hardware is up to it.  In fact, it puts the original YASNAC controller on my Matsuura mill to shame.

Steve
Logged
coolfox
Active Member

Offline Offline

Posts: 40




View Profile
« Reply #9 on: November 30, 2013, 05:48:22 AM »

Steve
Thanks for explanations
I my be thick, still dont get it.
According to your code ( lathe) this is point coordinates in LI mode  were is smoothing performed no IT comands implemented.
Could you plese help little more look for sample curves attached and how would thi Mash Galil communication would be dealing with this ?
Many thanks in advance
ILia


* Original Curve 01.JPG (17.99 KB, 420x200 - viewed 33 times.)

* LI curve.JPG (18.59 KB, 420x200 - viewed 29 times.)
Logged
Pages: 1 2 »   Go Up
Print
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!