MATC_recovery

[themoonlight 0]

Hi all,

I am using MATC instruction (time vs position). I am stuck with pause operation, it always start from zero and I wanted to do the following:

once the Estop pressed I need to pause the cam, and once Estop removed the slave should continue at where its stops.

can someone help me with by providing some info/codes on how to perform it?

Thanks,

[Jobbe9000 5]

Hi,

First of all you have to remember that working with cam profiles is always done incremental, and that is why it always seem to start from zero.

I suspect that you use the MAS or MSO to "Pause" the axis?

And that you use the STO (Safe torque off) either with CIPSafety or hardwired?

When the STO is activated the drive issues a MSO by itsself, which is simalar to issuing an MAS instruction to stop all movements, gearings, cams etc. and this brakes the link between the time master and your axis.

 

There are 2 ways to solve this problem:

If you want to continue using a time cam, you will have to do some math and scale your time cam before starting it after an E-stop. This can however be very tricky if the axis is working together with other axes.

 

The (in my oppinion) better and more safe way to do this, is by looking into virtual axis and position cam. A virtual axis is not affected directly by STO because it as the name suggests, does only exist in virtually and cant cause any danger in the real World.

The way that you would handle this, is to create a virtual master, and a virtual axis excatly matching your physical axis in settings, scaling etc.

Then use a MAG instruction to gear the physical axis to the virtual axis. before excecuting the cam profile. In case of an E-stop, you will stop the virtual master and the other virtual axis and the physical axis will stop together with the master axis.

Once the axes are stopped by a controlled stop, you can activate the STO function on the physical axis, which will only brake the gearing to the virtual axis.. the virtual axis is still linked in a cam profile with the virtual master axis.

Once the E-stop has been reestablished, you are able to gear the physical axis back to the virtual axis and start the virtual master again.

 

I hope it makes sense and that you will figure it out.