Robots vs CNC Machines

FANUC R2000ib 125L R30ia Motoman MA1400 FANUC M710ic 50 Motoman HP6 NX100 FANUC Arcmate 120ic
Industrial robots and CNC machines were both introduced to manufacturing around the same time during the 1960s. Both have been deployed to automate production lines in order to reduce the amount of human involvement with manufacturing processes for more efficient operations. While these technologies both serve the same purpose, they are actually quite different from one another. Understanding their characteristics and differences can help you decide which automation technology will best serve you.

What is an Industrial Robot?

An industrial robot generally consists of a single robot manipulator arm that is attached to a rotating base. Most industrial robots have between three to six axes, which determine the range of motion of the robot. The FANUC Lr Mate 200ic is an example of a six-axis robot, while the FANUC M-410ib/160 has four axes. Attached to the end of the robot arm is the end-effector which is the device used to interact with workpieces. Articulated robots are programmed using either a teach pendant or computer software. They can be used in most manufacturing applications including welding automation, robotic assembly, automated material handling, material removal automation, robotic machining, and robot palletizing.

What is a CNC Machine?

CNC stands for computer numerical control machine. It consists of a motorized tooling device and a motorized platform which are both controlled by a computer. CNC machines are programmed with specific instructions through G-code and M-code, which is usually generated by CAD or CAM software. CNC machines typically only move along three axes.

CNC machines are used to automate machining applications. These include drilling, milling, turning, and sawing. One CNC machine can only be programmed for one specific application. If you have a CNC machine programmed for milling but you now need to automate a drilling application, you would need a completely new CNC machine. These machines do not allow for changes once programmed.

Main Differences Between Robots and CNC Machines

  • • Applications - Robots can automate more types of applications than CNC machines. Robots can be used for machining processes as well as many other tasks. CNC machines are limited to just machining tasks.

  • • Flexibility - Robots provide flexibility with their ability to adapt to different parts and applications. With the FANUC M-20ia you can easily reprogram it should your manufacturing process change. CNC machines can only be used for one application and part type per machine, making manufacturing inflexible for future changes.

  • • Work Area - Industrial robots typically have large spherical work envelopes. Their range of motion allows them to access difficult angles, hard to reach parts, and to change positions. CNC machines have a much smaller work envelope than robots, consisting of a stationary cube. CNC’s cannot access difficult angles or positions the way robots can.

  • • Human Interaction - Industrial robots are capable of operating autonomously. They can retrieve their own parts, position them, and transfer them to the next workstation. This significantly reduces the need for human interaction and the chance of human errors causing manufacturing issues. On the other hand, CNC machines still require some human involvement. While they can automate the machining process, they need assistance with all other aspects such as retrieving parts and positioning them.



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