What is a Collaborative Robot (Cobot)?
A collaborative robot (also called a cobot) is designed to work with a human operator, positioned near them in a shared workspace. For example, the operator may perform the first part of a task while the cobot finishes the rest.
Collaborative robots are being designed as inherently safe to work around people. This involves new ideas for robotic arms including reducing their strength and speed, new types of joints, softer materials, and using advanced sensors to shut down the cobot safely if it accidentally collides with someone.
There are four types of collaborative robot features according to ISO 10218-1 and 10218-2. These include:
Safety monitored stop
Speed and separation monitoring
Power and force limiting (PFL)
Each of these features, individually, qualifies a robot as collaborative.
Modes for Collaboration
What are Power and Force Limiting Features?
Sensors in each joint — any value detected by the sensor will be compared to standard state and evaluated in order to perform an action (i.e. stop, move away from the force, etc.)
Hand guiding — easy and intuitive robot path programming by dragging the arm around its working envelope and registering positions and end effector actions
Round shaped design — created to smooth the surface, remove sharp edges from impact dissipation, integrated motors and wiring, pinch point free design to prevent hand squeeze, lightweight
Additional safety options — soft active or passive skin (jacket) for softened impact
A cobot in PFL mode will have slower speeds than an industrial robot
Let's take a look at a collaborative robot's axes
An industrial robot, whether collaborative or traditional, has various axes configurations. Six-axis robots allow for greater flexibility and can perform a wider variety of applications than robots with fewer axes. The diagram below indicates each of the HC10 robot's six axes.