As New Robots Appear, So Do Safety Requirements

Increasing demand for robots on the factory floor and within warehousing environments is shining a light on the importance of safety requirements that ensure robots do not harm humans working alongside them. Changes in technical capabilities, including the rise of autonomous mobile robots that slow down or stop near humans, require that companies understand the need for comprehensive robot safety training for those working with or near robots.

For more than 35 years, the International Robot Safety Conference (IRSC) has examined key issues around robot safety to provide an in-depth overview of the latest industry standards and best practices. The IRSC, hosted by the Association for Advancing Automation (A3), returns to an in-person event in September 2022, gathering in Columbus, Ohio, from September 27^th through the 29th.

Conference organizers say they have two main audiences that can benefit from the show. The first includes people who are new to robotics and industrial safety and are exploring robot deployments – the show will provide them with the basics of safety principals and requirements related to industrial robotics. The second group includes technical experts who have likely attended an IRSC event in the past but are looking for updated information about new robot standards in the pipeline (such as R15.08 for mobile robots) and any revisions to existing standards.

“The thing to remember with safety standards is that they’re continually being updated,” says Carole Franklin, Director of Robotic Standards Development at A3. “If you went to IRSC 10 years ago, you’ll need to come back and hear what has been done in the safety standard world since then. We want to keep the technical experts apprised of updated requirements that are being changed in the standards today.”

The key robot safety standards

The main safety standard for industrial robots is ISO 10218, (Part 1 and Part 2), which provides requirements and guidelines for the safe design and protection methods of these robots.  It was developed by the ISO Technical Committee TC 299 Robotics. In the U.S., these two parts were adopted as ANSI/RIA R15.06-2012.

The standards cover several key requirements for industrial robots, such as the use and setup of safeguarding equipment, protective measures, and the need for a safety risk assessment. A risk assessment sets usage limits for the robot, identities tasks and potential hazards, estimates the risks involved, and sets up risk reduction measurements along with documentation procedures.

Since the publication of these standards, the industry has evolved and developed additional robot form factors that require additional safety protocols. For example, the emergence of collaborative robot systems, such as those from Universal Robots, allows for the potential removal of some safeguarding measures due to slower speeds and sensors that can detect when a human worker is close to the robot.

“With the advent of the collaborative system, you had technologies that might make it possible to reduce or eliminate safeguarding,” says Franklin. “But in some cases, we find that it actually still is necessary to have some degree of safeguarding, but it’s a possibility where it wasn’t before.”

The rise of collaborative robot systems led to the establishment of ISO/TS 15066:2016 (international) and RIA TR15.606-2016 (U.S.). These standards specify safety requirements and guidance for collaborative industrial robot systems while still utilizing fundamental rules established in the previous standards (ISO 10218-1 and 10218-2 and RS15.06). “For the requirements of collaborative, you need to have an understanding of the foundational standard, but then you need to add TR15.606,” says Franklin. “In terms of understanding, it’s like another scoop of ice cream on the cone. But it actually might result in there being fewer fixtures in the robot system. It’s possible to design and build a collaborative robot system, it might not need a separate physical guard. It might look as if there’s fewer pieces of equipment, but in order to achieve fewer pieces of equipment, you have to have more information.”

Enter mobility

The next big paradigm shift around robot safety occurred more recently with the advent of autonomous mobile robots (AMRs) that can move around a factory floor, a distribution center or a warehouse.

“Even in the move from conventional to collaborative robots, you personally had to approach the machine in order to be exposed to its hazards,” says Franklin. “With mobile robots, the machine can move on its own, and therefore it can approach a person without the person intending to interact with the machine, or even being aware of the machine. So the robot has to carry its safety measures along with it in order to protect people that might become exposed to its hazards. That’s a very different mindset than in the fixed world.”

To address this, ANSI/RIA R15.08-1-2020 (Part 1) was developed, which addresses safety requirements for industrial mobile robots, most often seen in factories and warehouse environments. The standard was developed by bringing together experts with a wide range of backgrounds, including those who worked with fixed-in-place industrial robot safety, mobile robot manufacturers, advanced sensor technology developers, and end users. The committee that developed this standard is currently developing Part 2, which covers safety requirements and system integration guidance. A Part 3 is expected to provide safety requirements for users of industrial mobile robots and robot fleets (IMRFs).

An example of what might be covered in Part 2 is the consideration of different potential environmental hazards and how the mobile robot needs to respond. “For example, depending on which IMR system you’re deploying, its sensors might be confused if someone opens a cargo bay door and lets in a flood of sunlight,” says Franklin. “Humans see additional sunlight and that helps us see better, but for some kinds of mobile robots that flood of sunlight might confuse their sensors, which could potentially impact their ability to perceive a human and stop without running into them.” The committee is currently refining the requirements that would need to be met in order for an integrator to say a robot system is in compliance with Part 2.

Other safety questions to consider

When performing a safety assessment, companies and systems integrators need to also consider the types of materials that are attached to an industrial robot arm, or the payload that a mobile robot might be carrying. A classic example given around robot arms is that the arm itself might be completely safe, but if it’s holding a knife or a welding torch, that also needs to be included in the assessment.

Similarly, if a mobile robot is transporting hazardous materials around a warehouse, the operation needs to be sure that safety rules are followed for the payload, similar to how they would be followed if it was driven by a human forklift operator.

Future robot types that include both a mobile component and robot arm attachment (sometimes referred to as mobile manipulator) need to include safety assessments for both parts of the robot – again, the tasks and approaches differ depending on the environment. This is the main reason why safety assessments for both systems integrators and the companies deploying the robots are so important.

Franklin said the robotics and automation industry has been very good about adopting safety approaches for the equipment that enters a manufacturing or warehouse facility.

“The safety of people around industrial robots is a testament to our industry’s commitment to safety,” says Franklin. “It was recognized through the 1970s and early ‘80s that ‘These machines are extremely powerful and people can be hurt or injured.’ So for our industry to succeed, it’s almost a ticket of entry that we ensure that people will be safe around those machines. People automate for a large number of reasons, such as efficiency, increasing throughput or reducing bottlenecks, but you would not want to do it at the cost of introducing new hazards. I feel like our industry is still very committed to that.”