Accessing robot TCP pose from external machine in real-time

andreasbaldur

What is the recommended way for an external machine to retrieve the robot TCP pose if latency is critical?

To give some more context: I'm developing a vision application for an ABB IRB robot where the application is run on an external machine that needs to know the position and orientation of the robot TCP in real-time.

I'm aware of the PC SDK that could potentially be used to retrieve this information, but I'm questioning the latency and reading rate by using this approach.

Best Regards,

abaldur

soup

Can you give a number to the latency requirement?

andreasbaldur

Hi soup,

If possible, something like 1-10 ms latency with 100 Hz update rate would be great.

Do you think there are any ways to achieve this?

/ abaldur

nomad5t5

With the option "EGM" you can stream the current and predicted TCP position and time.  The latency is approxinmetely 8 ms with a 250 Hz refresh rate. 

andreasbaldur

Thanks. That sounds pretty much like the option I'm looking for!

What communication interface is used with the EGM option? Is it based on Ethernet?

If I do not need to control the motion of the robot, but only monitor the TCP position, will there then be a more appropriate option for that?

Looking at the list of IRC5 options, I can see that there is also something called "Sensor Interface: Toolbox to integrate sensors based on serial communication.".

How does that differ from the EGM option?

/ abaldur

nomad5t5

Bundled with the EGM option is Robot Reference Interface (This used to be a separate option before the introduction of EGM).  This will allow you to stream the robot position to an external device.

The Sensor Interface option is used for creating customized path correction for seam tracking of welds, etc.