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Messages - smurph

1241
Galil / Re: Kitamura T-12 with Galil DMC-1840 and Contec I/O Setup
« on: July 14, 2013, 04:02:24 PM »
I completely agree with Mike.  If the motor is running away with SH, then you probably have an encoder problem. 

The motor encoders can be logically reversed with the Galil MT command.  Read up on that one.  Also, the Galil can be setup to keep runaways from causing problems.  See the OE (OFF on error) command.

As to the OFx needing to be adjusted every time, that is going to be an servo drive amplifier issue.  The Galil will apply the same voltage offset every time.  Could there possibly be some change in resistance on that circuit?  The Fanuc drives you have may operate on a PWM control input.  So I guess that third party device converts analog voltage signals to frequencies that the drive understands.  If this is the case, then you may have an offset issue in the V to PWM device.  You must check this and make sure that the frequency output is stable with regards to voltage applied.  Also, devices like this may float if there is no input, which may explain your drift.

But this is a hard problems to solve on any servo system.  The main way people handle it is to remove power from the servo amp when there is no command voltage.  This is why the SH and MO Galil commands operate the AMPENx signal.  I would strongly suggest working this into your control circuit.  You can leave the Opto22 relay intact.  Just wire the AMPENx into the circuit in series so that both the Opto22 relay and SH need to be active to enable the servo drive.

Torque and Velocity refer to the mode by which the servo drive operates, not by how it is controlled.  The Galil cares not whether the drive is torque or velocity.  Only the Galil PID values may change between the two modes.  Tuning is accomplish the same way regardless.  You are simply looking for a command response that fits your needs.  If you have a servo drive that will do either torque or velocity, one may work better than the other for any particular application.  But if you only have velocity control...  then that is what you are going to use.  :)

Steve

1242
The Contec cards were hooked to the Opto 22 stuff.  Maybe purchasing a Contec card it the easiest way.  Otherwise, you will have to find someone to write a plugin for the ADLink cards.  I would, but I just don't have the time right now as I'm busy busy busy with Mach 4 at the moment.  If you get a Contec card, make sure that it is supported by the plugin.  (I think it is in the docs).

Steve

1243
There is no plugin for the ADLink cards as far as I know.  I wrote one for the Contec cards, which CamSoft seemed to have used at one time.

Steve

1244
Galil / Re: DMC1842
« on: June 27, 2013, 08:24:03 PM »
You need no Galil code at all.  You will have to burn your PID values into the NVRAM though.  As Allen stated, you have the option of running Galil code in threads.  For example, my whole tool changer is run from Galil code.  But nothing is required beyond plugin config to configure a MPG.

Steve

1245
Galil / Re: Kitamura T-12 with Galil DMC-1840 and Contec I/O Setup
« on: May 31, 2013, 06:06:52 PM »
Not sure what was running the machine before hand.  Galil + Contec smells like camsoft to me.  I really don't know how camsoft saves the motor tuning values.  With Mach3 and the Galil plugin, we require that the motor tuning is burned on the card.  

So the main thing that needs to be burned into the card is the PID values for each motor.  MG KPA; MG KIA; MG KDA;, etc...  will show you the values.  I think stock is 64, 0, 64 but I'm not real sure.  So if you see something low like that, then you are going to have to tune the motors.


1246
Galil / Re: camsoft conversion
« on: May 03, 2013, 04:16:46 AM »
Can you move the motors through SmartTerm?

6, 0, and 64 sounds like the default PID values.  You must tune your servos to your system.

The plugin will not do magical things to set up your Galil servo system.  So generally, you tune the servos and get the motors moving in SmartTerm before attempting to use the plugin.  

Then, you will need to configure the plugin.  You will need to map Mach axes to Galil axes in the plugin as well.  (axis mapping tab).  This is all covered in the plugin documentation.

Steve

1247
Galil / Re: camsoft conversion
« on: April 29, 2013, 12:54:42 PM »
No adlink plugin that I know off.

1248
Contec / Re: Contec Plugin not working
« on: April 29, 2013, 01:18:38 AM »
The Contec plugin requires that you have the Contec DIO drivers installed on your PC.  You can download them from their web site.

The plugin is not defective.  Mach gives that message for any reason it cannot load a plugin. 

Steve

1249
Galil / Re: camsoft conversion
« on: April 29, 2013, 01:11:05 AM »
That failure message really means that the plugin cannot load because it cannot find the Contec drivers.  The plugin is not defective, that is just what Mach displays when it can't load a plugin for any reason.  You will need to install the Contec DIO drivers.  You should have a CD with them on it or you can download them from the Contec support site.

1250
Galil / Re: Galil Slave Axis
« on: March 28, 2013, 05:39:14 PM »
We can't just dump Gcode to the Galil, unfortunately.  Lots of problems with that.  There is no Gcode to Galil code translation that matches up 100%.  For example, there is no way to do a helical move in Galil code.  (thread milling).  The CR command is 2D only (vector mode).  Now, one could possibly work out an ecam based on the position of the X and Y axes and then gear the Z to the ecam.  But that would involve loads of calculations that had to be done at the time of the helical move.  

The bottom line is that Mach is providing a lot of stuff that a G code machine controller should do that the Galil cannot natively do.  Believe me when I say that Kenny and I have thought about this plenty!  If we could use Mach for things that the Galil can't do very well on its own and use all Galil code for the rest, then that would be awesome!  The problem is that it is all or nothing.  :(

The KS command on the Galil has the distinct disadvantage of being in effect all of the time.  I played with it for a bit.  To effectively use it with Mach, we would have to change it's value constantly depending on accel, decel, or slew conditions.  There is no static KS value that we can use to cover all types of motion.  We would have to build a lookup table in the config so that the user could set KS values that work for their machine.  Then we would have to detect accel, decel, and slew conditions in the plugin and set KS accordingly.  That is a a lot of work to run steppers on a motion controller more suited to run servos.  There is no doubt that smoother stepper motion can be achieved with KS, but it is much more suited to working with a hand written Galil motion program that is designed to be "run" on the controller.

Of course, the higher the resolution (steps per rev) the motors/drivers are capable of, the less of an issue all of this becomes.  Step "spacing/smoothing" is needed less.  Servos tend to be geared down and have much higher steps per unit than steppers do.  My servos do 12700 counts per inch.  Way less than one micron resolution making the smoothing issue a moot point.

The good news is that I can happily report that Mach4's motion is much smoother.  There are some videos Brian put up on you-tube that are quite impressive.  Still no 3rd order, but it is definitely less "pausey" than Mach3.  3rd order is coming though.  With Mach4, I'm planning on taking advantage of the newer Galil controller's PVT mode.  It should be a great combination.

Steve