In a “speed and separation” manufacturing scenario, a safe distance must be maintained between a collaborative robot and a human operator. When the gap reaches below a specific threshold, the cobot then initiates a monitored stop. But how does the robot “see” the human?

During a recent presentation titled “Integrating Motion Control for Safe Robot Operation,” a Tech Briefs reader asked our expert Joe Falco, National Institute of Standards and Technology Engineer (Intelligent Systems Division) the following question:

Joe Falco, NIST

How does the robot know when the operator is entering a workspace?

Falco: That's an implementation detail that's left primarily to the integrator of the robot; safety standards for collaborative robots will not specify. In an implementation I showed at NIST , we had laser scanners looking at the ankle level of operators within the collaborative work space. It could be a vision system. It could be something as simple as a light curtain or other sensing system that detects a person's presence within a collaborative workspace.

In the case of speed and separation monitoring, where you might have several operators within a collaborative workspace, it gets pretty complicated at that level. You need to work out issues such as occlusions, like one operator standing close to another operator. Human detection and monitoring is a huge research area within the robotics arena, especially when applied to collaborative robotics technology.

What do you think? What are the best ways for collaborative robots to sense human presence? Share your thoughts below.

Also: Read Falco's response to a reader who asked: "How Are Collaborative Robots Being Used Today?"