The Four Types of Collaborative Robot Operation

Collaborative robots are becoming increasingly popular in manufacturing. As more companies adopt automation, there are many tasks identified that require people to work in collaboration with a robot. Let’s examine the four types of collaborative robot operation:

1. Power and Force Limiting cobots

Power and force limiting cobots are likely what most people think of when they hear the term collaborative robots. They are designed specifically to sense contact with people and cease operation, eliminating the need for safety barriers. They are best suited for smaller applications.

For the three other types of collaborative operation -- any industrial robot can be integrated with safety devices to become “collaborative.”

2. Safety Rated + Monitored Stop cobots

Safety rated + monitored stop cobots detect when a person has entered a designated area and stop operating until the person leaves that shared workspace, eliminating the need to have to restart a robot with the push of a button. Once the person leaves, the robot automatically continues its task. These are generally used when there’s not as much interaction between a person and a robot.

3. Speed and Separation cobots (also called “fenceless”)

Speed and separation cobots - more simply referred to as "fenceless" cobots - work well when there is not much interaction with a person, but a person needs easy access to the robot.  Safety laser area scanners are commonly used to set up zones near the robot’s workspace.  When a person approaches the robot, its movements slow down, and then stop if that person gets within reach of the robot’s workspace.   As soon as the operator moves out of the robot’s workspace, the robot automatically resumes normal speed.

4. Hand Guiding cobots

Finally, hand-guiding cobots have a safety-rated device attached to the end of the robot’s arm to allow a person to manually guide or move the robot around.  Hand guidance is often used to quickly and easily program new robot paths and positions by hand. It’s ideal for mobile applications where the cobots move between stations and require re-training to accomplish different tasks, and when the cobot needs to be reprogrammed frequently for a new job.