Pressbrake CNC Control Setup Questions

Here is the halscope plot.
Just to verify, when homing towards index, the home switch turns active just before reaching index point.
Index is on home switch active true side.

 

Can you plot the commanded and feedback point positions?
These should both be set to 0 when index is detected

PCW wrote:

Can you plot the commanded and feedback point positions?
These should both be set to 0 when index is detected

 

That does look about like what is expected, on index both the commanded
and feedback positions are zeroed. What is the home final velocity?

Can you plot the joint equivalents of the feedback and commanded positions
(plus the joint following error)

Another useful thing to plot would be joint.0.home-state

PCW wrote:

What is the home final velocity?
 

There isn't one here. This is a weird setup that I created that uses just a Python GUI and a HAL component. There is no INI. 

I'm using the pressbrake to do simple bending jobs. Now I see the need to add the tonnage pressure limits we had mentioned earlier.

andypugh wrote:

I think pressure limits need to go in the press .comp.
Adding another state "overpressure" that only allows motion up.

 

It would be nice to have a hal input pin to set the tonnage limit anytime the ram is moving down.
If the press exceeds the tonnage limit, motion should stop and only up motion allowed.
Depending on the tooling and job, the tonnage limit will need to be adjusted from the GUI.
 

I have made a start at this, but I am short of time. 

 

The pressure gauge now updates as the max pressure is changed. 

I have also added an overload state to the state machine. I don't know if it works...

press.comp now needs it's max-pressure pin connecting to the UI max-pressure-f pin so that it is aware of the limit. 
Both the UI and the comp need to be connected to the pressure meter output. 

What is your current situation with homing? I have been sat on your last message in my inbox waiting for it to make it to the top of my queue. 

 

andypugh wrote:

What is your current situation with homing? I have been sat on your last message in my inbox waiting for it to make it to the top of my queue. 

 

So far I'm only using the ram, not the backstop.
I can home the ram ok because with its shorter travel distance the rapid move during homing doesn't cause as much of an issue.

EW_CNC wrote:

So far I'm only using the ram, not the backstop.
I can home the ram ok because with its shorter travel distance the rapid move during homing doesn't cause as much of an issue.

I will try to get on to this, possibly at the weekend, but I am away from my LinuxCNC machines for the next few days.

andypugh wrote:

I have also added an overload state to the state machine. I don't know if it works...

 

I halcompiled the press.comp with the overpressure changes, made the connections in the GUI and hal file.
The new pins show correctly in halscope, but down motion does not stop when pressure exceeds max pressure setting.