Industry Standards, and Standard Equipment, Bolster Mobile Robot Safety

By: Michael Ejstrup Hansen, Contributor

An autonomous robot from Mobile Industrial Robots equipped with a ROEQ top roller module. Image courtesy of ROEA.

Companies are eager to take advantage of exciting new automation technologies that promise to boost efficiency, productivity and competitiveness. The challenge, however, is that standards organizations can struggle to keep up with technology advances. While safety standards are being developed, communicated and adopted, the burden is on technology integrators—either the companies themselves or third-party integrators—to ensure that workers who come into contact with new equipment are protected from harm. But even if the equipment itself is deemed safe, the way the equipment is installed, configured and used can still introduce risks.

Autonomous mobile robots (AMRs) are a case in point. While these robots are designed with extensive safety mechanisms to protect workers, the robot itself is only one part of the overall automated system. The robot is completed with mobile robotic equipment (MRE) that can include a range of cart and pallet lifters or top roller modules, as well as intelligent hardware and software interfaces to equipment, such as conveyors. The system also includes the rest of the environment in which the robot operates, including charging and material transfer stations and other equipment the robot interfaces with.

Safety Standards

To implement safe systems, companies and integrators have had to depend on an array of legacy standards until new AMR-specific standards are ratified. These legacy standards, such as the European EN 1525:1997 and the American ANSI/ITSDF standard B56.5-2019, were developed for driverless industrial trucks and automated guided vehicles (AGVs), which are typically larger and heavier than AMRs and are implemented quite differently. Importantly, these standards don’t address autonomous navigation, which is central to mobile robots’ safe operation.

Of course, manufacturers of mobile robots and standard MRE are watching new standards closely, such as ISO 3691-4, which is a new adaptation of ISO 13849 for driverless industrial trucks. For example, ROEQ’s standard top roller module that interfaces with conveyor systems already includes safety functions in line with ISO 3691-4. These features protect workers from injury by ensuring that the conveyor is not in operation while the robot is moving.

But while standards organizations are working hard to adopt and communicate new guidelines to address everything from the design of the robots and MRE, to full system implementations, that process takes time. In the meantime, companies are eager to gain the advantages of mobile robots, so are doing their best to apply legacy standards that are the only guidance they have.

Challenges Arise

ROEQ’s Guardcom interface. Image courtesy of ROEQ.

One of the challenges during this time is the tremendous growth the industry is experiencing. There are already hundreds of thousands of mobile robots in operation. And according to ABI Research, the global market for autonomous mobile robots is forecasted to grow from USD $800 million in 2020 to an astounding USD $49 billion by 2030. That growth is making it hard for integrators to keep up with new technologies and guidelines for safe implementations.

Another challenge for integrators is one of mobile robots’ key advantages: their configurability. The robots themselves are intelligent platforms for a growing array of MRE, similar to the relationship between traditional 6-axis robot arms and application-specific end-of-arm tooling. In both cases, the robot moves the tool or mobile equipment into position to accomplish an automated task.

Today, there are few vendors who are developing standard MRE that is designed specifically to match and complement the safety mechanisms of autonomous robots. That leaves integrators who are more familiar with forklifts and conveyors to try to develop custom modules and other equipment for their application, or to integrate conveyors, racks or carts that were not designed for autonomous use. With limited experience, many of these integrators are focused on solving their implementation challenges and integrating mobile robots into existing plant layouts. In the process, we’re seeing many of them inadvertently negating the safety mechanisms built into the robot or introducing new risks through the use of non-standard MRE. The company assumes the robot’s built-in safety mechanisms are still reliable, but workers may be in danger.

This use of non-standard MRE can lead to a range of safety hazards. For instance, mobile robots require an emergency stop button that is within reach of no more than 60cm so a worker can easily stop the robot if necessary. However, we have often seen non-standard top modules that are either too large themselves to meet that requirement, or that are set up to carry material that is too large to allow access to the emergency stop button. In contrast, standard MRE is designed for current and upcoming safety standards. For example, ROEQ’s extended top module places the emergency stop button within easy reach even when loaded with oversized goods.

AMRs are designed with extensive safety mechanisms to protect workers, but the robot itself is only one part of the overall automated system. The robot is completed with mobile robotic equipment that can include a range of cart and pallet lifters or top roller modules, as well as intelligent hardware and software interfaces to equipment such as conveyors.

What has become clear is that the combination of industry standards along with standard equipment will bolster the safe implementation of mobile robots. Standards establish rules that MRE and AMR vendors follow closely so we can more efficiently meet global market needs. When customers implement these standard products and follow manufacturers’ guidance for integrations, they can have more confidence in the system’s safety than a custom integration can offer. In addition, standard systems run the same way every time, even if robots are rolled out over time. Software built into the robotic equipment is tested and proven, and each MRE from the same vendor will work exactly the same way as the rest of its products, with common safety documentation that eases compliance with local safety regulations.

Of course, many third-party integrators are also following safety standards closely, but their ability to develop one-at-a-time customized systems that meet standards can become cost-prohibitive. In contrast, standard MRE manufacturers can spread safety development costs across hundreds or thousands of products, making those products more cost effective, as well as safer.

For companies that are eager to take advantage of innovative mobile robot technologies, the combination of standard products and industry standards is a win-win. WMHS

Michael Ejstrup Hansen is Managing Director, ROEQ. ROEQ develops standard mobile robotic equipment designed specifically to complement the safety mechanisms of autonomous robots. The company’s Guardcom interface connects the AMR’s top roller and the stationary conveyor station enables safe, reliable and cost-effective handling and transfer of goods between AMRs and the conveyor station