G-code and driving robots.

I've found a lot of talk but surprisingly little answers. Can you drive a 7 axis robot directly with standard Gcode? I know G53 is moving in absolute machine units but how does it handle rotational axes since milling mainly deals in linear? No experience in 5 axis milling so do they specify those values as angles or some other units?. Or could you use G1/G0 with say, G90 to move at different speeds and control feedrate etc.?

I also have a ROS output that outputs trajectories as joint angle values(deg or rad) and I'm thinking can that be converted to G-code by simply taking each value and assigning it to a G53 X<value> Y<value> etc. format? And in the same vein use a program to record the current joint values and insert dwells etc. and create robot programs this way?

Also with the proper kinematics, could you input a standard 3 axis milling G-code program and have it used as cartesian coordinates system? How would this work?

Roiki wrote: Also with the proper kinematics, could you input a standard 3 axis milling G-code program and have it used as cartesian coordinates system? How would this work?

It works quite well, once the kinematics is set up right.

There are lots of examples of LinuxCNC driving robots in just this way. One example:

Good to know its in the realm of possibility, and that looks like exactly the thing I'm thinking about. But do any examples or more detailed information exist?

There are simulation config with virtual 3D animations of a robot arm included with Linuxcnc. (See Vismatch)

I'm aware and I have a simulated config without kinematics for general testing but without the hardware it's kind of hard to prototype things.

I'm more looking for information on how gcode could the used to command robot positions and maybe examples of information how others have done it.

There are two basic ways that a CAM program can create g-code. One is direct 1 to one joint manipulation. This the CAM program must have specific knowledge of the machine's kinematics and the resulting code is machine specific. The other way is using tool center point commands. This way the g-code is generic. The g-code simply specifies the position and orientation in Cartisien space with xyzabc coordinates, abc are angular. And the machine control handles the kinematics work.