Cobot

Overview

A cobot, also called a collaborative robot or companion robot, is a machine designed for direct human-robot interaction within a shared workspace. Unlike traditional industrial robots that operate behind protective barriers, cobots work alongside humans in close proximity.

Safety features typically include "lightweight construction materials, rounded edges, and inherent limitation of speed and force, or on sensors and software that ensure safe behavior."

Uses

The International Federation of Robotics recognizes two main robot categories: industrial robots for automation and service robots for domestic and professional use. Cobots remove the traditional separation between humans and machinery.

Applications span diverse fields:

• Information robots in public spaces
• Logistics robots for material transport within buildings
• Industrial robots assisting with unergonomic tasks like moving heavy components or assembly operations

Four Levels of Collaboration

The IFR defines collaboration intensity as:

1. Coexistence: Humans and robots work alongside each other without shared workspace
2. Sequential Collaboration: Both work in shared space but take turns; no simultaneous work on the same part
3. Cooperation: Robot and human work on the same part simultaneously, both in motion
4. Responsive Collaboration: The robot reacts in real-time to human worker movements

Currently, most industrial cobot applications involve coexistence or sequential collaboration, with cooperation and responsive collaboration being less common.

History

Cobots were invented in 1996 by J. Edward Colgate and Michael Peshkin, professors at Northwestern University. Their U.S. patent describes "an apparatus and method for direct physical interaction between a person and a general purpose manipulator controlled by a computer."

Brent Gillespie, a postdoctoral researcher, coined the term "cobot" and won fifty dollars in a naming contest for the designation.

The invention emerged from:

• A 1994 General Motors initiative led by Prasad Akella of the GM Robotics Center
• A 1995 General Motors Foundation research grant seeking to create robot equipment safe for human teamwork

Theoretical foundations were established in the mid-1980s by Oussama Khatib at Stanford University, with further refinement by Gerd Hirzinger's team at the German Aerospace Center.

Early Development

Initial cobots used no internal power source; humans provided motive power while computers controlled motion. Later versions incorporated limited motive power capabilities. General Motors and industry groups used the term "Intelligent Assist Device" (IAD) as an alternative, viewing "cobot" as too closely tied to the Cobotics company.

Target application areas included manufacturing and orthopedic surgery. The Cobotics company was later acquired by Stanley Assembly Technologies.

Standards and Guidelines

Safety standardization has developed progressively:

• RIA BSR/T15.1: Draft safety standard for Intelligent Assist Devices, published March 2002
• ANSI/RIA R15.06: Robot safety standard first published in 1986; updated in 1992, 1999, and 2011 as a national adoption of ISO 10218-1 and ISO 10218-2
• ISO/TS 15066:2016: Technical specification covering collaborative robotics requirements and integrated applications
• ISO 10218-1: Requirements for robots, including optional collaborative capabilities
• ISO 10218-2:2011: Safety requirements for both collaborative and non-collaborative applications

Important Distinction

The term "cobot" is considered marketing terminology rather than an official standardization term. Safety depends on the specific application: "a robot wielding a cutting tool or a sharp workpiece would be hazardous to people. However the same robot sorting foam chips would likely be safe."

Risk assessment by robot integrators addresses intended use according to ISO 12100. In Europe, the Machinery Directive applies, though the robot alone is considered a partial machine; the complete system includes the robot, end-effector, and application context.

See Also

• Air-Cobot — a collaborative mobile robot for aircraft inspection
• Automated guided vehicle (AGV)