Posts by CNCRobot

Milling in hard materials was always a challenge for robots given their low stiffness. This lead to the robot's TCP being pushed away from the programmed path by the acting process forces.

The solution is to simulate the occuring process forces, material and tool dependent, and subsequently to compensate these forces to increase the robot's path accuracy and thus the workpiece's quality. For example a milling application on a complex contour with a robot leads to a workpiece tolerance of +-0.2mm, a good result for a robot roughing application. Check the application in the video, material is aluminium alloy EN AW-6005A:

If you use a CNC controlled robot where you compensate for the material and tool dependent process forces that push the robot TCP away from it's path, you can even get a workpiece quality of +-0.2mm on a complex part in aluminum. This is quite good to keep the roughing tolerances for a machine tool

MABI Robots have a very good backlash compensation since they also have a secondary encoder installed after the gear on each of the robot axes:

https://www.mabi-robotic.com/r…m/product.asp?IDProdukt=5

Quote from SkyeFire

There's several factors in play here:

1. The robot has to have a controller of some kind, and robot controllers are much more complex than CNC controllers, due to the different kinematics. You're basically stuck either buying a good KRC2 with compatible hardware (check with KUKA, using the serial# of your robot, to find out what's compatible), or buying something like a Siemens 840D controller and a kinematic module for the 840D matched to your controller.

2. Robot's don't speak G-Code natively. You either have to buy an add-on module for the robot that "translates" G-Code on the fly, or use a CAM postprocessor that generates "native" robot code. Either of these options have some additional risk, in that simply outputting 5-axis-style path programs can cause issues for the robot (kinematics, again), so your CAM toolchain really should be "robot aware" -- should have the capability to import a model of the actual robot you're using and simulate its motion, so you can avoid wrist flips, elbow collisions, and other motions that articulated robots have, and even the highest-level CNC machines don't.

3. Robots simply don't have the rigidity or accuracy of CNC machines (closed vs open kinematics, parallel vs serial kinematics, etc), so even if you can jump the software gap, you won't get CNC-grade output. Robots are designed for reach and flexibility, where CNCs are designed for rigidity and accuracy.

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There are robots which are directly controlled by CNC and don'T require any interface or interpreter, even with secondary feedback systems to compensate the robot backlash:

https://www.comau.com/EN/media…control-alongside-siemens

Comau robot arm controlled by a CNC controller:

https://www.comau.com/EN/media/news/2017/09/SiemensEMO

Hi,

check out this video then:

Best,

Victor