Hydraulic press brake control

Hi Andy,

I understand.

What i tested this week was to visualize a press a brake sequence program in the gremlin screen.

I made in the main gui python code a hal pin :
self.g = hal.component("Gcode")
self.g.newpin("X_start", hal.HAL_FLOAT, hal.HAL_OUT)

Then the gui tab screen text input value to set the hal value :
self.entry = self.widgets.X_start
self.x = float(self.entry.get_text())
self.g = self.x

Then in the postgui.hal file make a x_start signal to use in variable g-code later on :
net x_start Gcode.X_start

Then in the gcode file :
#1 = #<_hal[x_start]>
G1 X#1

It will display the press brake sequence program according the excel sheet or gui screen input parameters.
In the end i think this will be a nice solution. The machine does not have to execute the g-code, it's only for displaying the
bending program.

Hi Andy,

I have tried and read the doc's of Vismach about 6 month's ago. It is very nice to see the actual press brake tooling and the product getting shaped.
Do you know if Vismach is updated in past time, as your link describes?
My knowlegde of linuxcnc is better as 6 month's ago, so i can look to adapt the Vismach screen to the press brake gui.

I was also thinking about adding features to the gremlin source code.
When you look at the displaying of the tiny red machine extend's line's, or tool Cone, i thought to investegate this source code to add some related lines or shapes for example to the Gremlin screen. To see what is possible. At the moment the Gremlin is very limited.

I received my boards and I'm working on installing them. I'm thinking that doing the closed loop outside the comp would be less code and trouble. Yes? And yes, my home sensors on the cylinders are at the top. My reasoning was that at the bottom is dependent on what punch and die are in the machine. I guess I could have put them somewhere in the middle.

Hi Steve,

The stepper motor closed loop outside the comp would be perfect!
End switches on top is good. I asked myself how your glass encoders are working.
If you have the glass encoders online, please provide the data from halmeter.
If the data on the glas scale is alway's the same at startup, or the data is alway's responding to position with the same value,
you can use this glass scale for home reference you and don't need to configure or add home sensor's.
This would be my first attempt to get the KIS. (keep it simple)
In fact with home sensor's you have to reset your glass scale data. So i am curious how this will respond in your system.
Good luck !! Take your time.

i'm using 300mm long from fast 2 buy on ebay. Attached is a link to them

Glass scales

So after your comments on encoders I'm thinking SSI absolute encoders would surly make things simpler. But that means getting a different board to read ssi. changing them out on the motors is no problem but for the cylinders I would be making a belt/pulley system to make them linear as absolute linear scales are way out of my budget for this. I'll have to call and see if the 7i96 will work with a 7i74.
here is a link to the encoders I've found.
encoders

also wondering if you couldn't call a single axis out in gui. pass that command to two separate axis (the cylinders) in velocity mode. hijack the velocity out command number (say max vel 65) into two position commands for the steppers. wouldn't linuxcnc keep the two cylinder axis in sync by adjusting the velocity for each cylinder witch would in turn change the position of the steppers running the valves? Or I'm I talking crazy?

Hi Steve,

I prefer you keep your hardware as it is now.
We make this working !

If you got the glass scale's working and have halmeter input, you pass can me your config files, i like comment's in your
config file's, that make's life easyer.

Okey.

For your cilinder movements we make a component.
The 2 stepper motor's will control 2 cilinder's.

The sychronisation will take place when we are pressing in full speed and in lower speed and with press hold time.
The component will read your glass scale value's. If one is behind, then the stepper valve of that cilinder wil move a little bit in degrees to compensate.

So don't worry about that.
The finetuning of your setup parameters will be done in the linuxcnc gui, and you can save this parameters in the gui.
So it will be easy.