Could New RIA Standards Improve Cobot Safety?
Despite the numerous safety features that are inherent in cobots—including collision detection and lightweight frames—appropriate safety measures must still be taken for the overall application.
Now, upcoming standards introduced by the Robotic Industries Association (RIA) could further address human-robot collaboration within shared workspaces and make them even safer still. That is, if companies are willing to adopt them.
These new standards are being introduced to help the RIA achieve its vision where “every robot integrator and user in the nation (or even, the world!) is aware of our robot safety standard, has a copy, understands it and uses that knowledge to keep people safe around robots.”
Rather than regulations created by a federal body with which industries are compelled by law to comply with, like OSHA standards, the RIA develops voluntary industry consensus standards. The RIA works closely with the International Organization for Standardization (ISO) to ensure that there is cohesion between standards worldwide, enabling companies to achieve compliance more easily.
How Do the RIA’s Standards Apply?
When writing its standards, the RIA clearly defines the difference between “robot”, “robot system” and “robot cell”.
As an example, industrial robots must fit all parts of the following definition, which is the same in both RIA standard 15.06 and ISO standard 10218-1, 2:2011: “automatically controlled, reprogrammable multipurpose manipulator, programmable in three or more axes, which can be either fixed in place or mobile for use in industrial automation applications.” Therefore, a device that operates in only two axes will not fall under this definition and thus the RIA’s standards would not apply to it.
What Safety Standards Apply to Cobots?
Cobots that are designed to work with human operators always have two defining abilities—force and speed monitoring. And when they are equipped with devices that detect when a human has entered the collaborative workspace, they are allowed to operate at higher speeds as per ISO 10218 and technical specification RIA TS 15066. These standards detail the requirements and information surrounding safe cobots.
Under TS 15066, the force and speed monitoring of the cobot is set based on application data, human contact area, and workspace hazards. Application data, possible human contact, and existing workspace hazards are all factored into any calculated safety settings based on TS 15066.
Additionally, ISO TS 15066:2016 and RIA TR 15.606-2016 outline the requirements and information concerning safe collaborative robots. In both documents, the content is virtually the same, but TS 15066 is normative (outlining the steps required for compliance) while TS 15.606 is informative (providing information that can be used for compliance).
The new RIA updates focus on mobile and collaborative robots, also referred to as cobots. Image used courtesy of Robotic Industries Association.
RIA's New Standards
Both documents describe the four collaborative techniques used to mitigate risk: safety-rated monitor stops, hand guiding, speed, separation monitoring, and power force limiting (PFL) systems.
ISO TS 15066 and RIA TR 15.606 are designed to also be used in conjunction with RIA TR R15.806-2018, which describes a method for testing forces exerted by a pressure force limiting system.
The RIA has made several recent changes to its standards, too.
Most notable is ISO 10218-2011, covering safety requirements for industrial robots and systems, which is earmarked for an update next year. The corresponding U.S. Standard, R15.06-2012, is a direct adoption of ISO 10218-2011 and will likely be completed in 2022.