How to Safely Add Mobile Robotics

© Strother – stock.adobe.com

Don’t let safety concerns stop you from integrating mobile robots into your workforce.

Contributed by: The Robotics Group of MHI

Mobile robots bring myriad benefits and potential to the table when implemented in a warehouse. They offer a solution for those facilities struggling to find qualified labor — which is a challenge for most organizations these days — increase efficiencies, boost productivity, and in the long run, can save you money, too. But for most companies that haven’t added robotics yet, concerns over robotic safety sometimes tops the list of barriers. That needn’t be the case.

“Without question, what people worry about most is mobile automation and how safely it can interact with humans,” says Sawyer Dillard, manager of advanced automation for Gray Solutions. “After that, they worry about robots and their interactions with other equipment.”

There are plenty of safety measures built into the equipment, which is generally considered autonomous mobile robots (AMRs), and to a lesser degree, automatic guided vehicles (AGVs). When you couple the built-in safety with a risk assessment and adequate training, you can focus on the benefits of mobile robotics and let your mind at ease.

BUILT-IN SAFETY MEASURES

When dealing with AMRs and AGVs, understanding how each maneuver around a warehouse is important. As the name implies, AMRs operate autonomously, meaning they have something of free range around your warehouse floor. AGVs, on the other hand, follow designated pathways and are entirely predictable in their movements. Despite their autonomous nature, however, AMRs are not simply on the loose–there is safety designed in.

“Potential customers worry about whether an AMR is going to stop if it ‘sees’ a human,” says Vinay Balay, safety engineer with ThirdWave Automation. “They may not stick to a specific lane, but they’re smart enough to navigate around obstacles to get from point A to point B.”

AMRs are loaded with sensors and LIDAR—light detection and ranging—a remote sensing technology that provides a full field of view for the robots. The makers of AMRs program them to detect minimum-sized objects, based off human dimensions. OEMS can also program AMRs to know zones within your facility to slow down and, come to full stops. This might include a workstation, for instance, to avoid contact with an employee standing and working.

Additionally, OEMs must adhere to safety standards when manufacturing AMRs. These standards include three that apply to AMRs. They include IMR Type A, which includes AMRs without attachments; IMR Type B, which covers AMRs with either passive or active attachments, such as conveyors or linear lift devices; and IMR Type C, which is an AMR with a manipulator.

Signage, marked lanes and crosswalks help people avoid the designated pathways for autonomous mobile robots. © SerPak – stock.adobe.com

ASSESSING FOR RISK

Performing a risk assessment is another essential step to ensure safety with AMRs and AGVs. “This is a chance to run ‘what if’ scenarios,” explains Dillard. “We take a look at what risks exist and how severe each is, then work to mitigate them.”

This might look at where/how a robot could potentially bump into a person, for instance. If you identify that potential, you’d work with your robotics partner to control traffic patterns, for instance, or reduce speeds in that area. You’ll draw up schematics that ensure the robots move with these zones in mind, potentially reorganizing workflow.

You should also consider the payload the vehicles will be carrying. “Make sure they are within the load ratings of the AMR,” says Balay. “You don’t want to put a package on a robot have it fall off. Know your payloads and know what the AMRs can support.”

TRAINING AND SIGNAGE, ETC.

After the risk assessment, part of your mitigation efforts will include training your staff appropriately, as well as adding signage and other materials to keep your AMRs operating safely. “Adding signs to remind employees to take caution will help keep them aware of the robots in their presence,” says Balay.

Dillard says that many customers choose to add gates and other safety mechanisms, especially around AGVs and their pre-set routes. “This is just an extra step that helps humans remember to stay out of the path of the vehicles,” he explains.

Training should also extend to safe use of other equipment in the vicinity of AMRs. Forklift drivers, for instance, will need to modify some of their behaviors when working near AMRs. This means adhering to posted speeds, utilizing proper turns, and following proper routes. Just as drivers learn to avoid collisions with humans, they can learn to avoid collisions with mobile robotics.

When it comes to your workers, they too, should brush up on their behaviors around this new moving equipment. Using marked crosswalks, not cutting across established lanes, and avoiding the tendency to cut corners on the floor.

Putting all the pieces together, you’ll have a more productive warehouse that ensures mobile robots and humans can co-exist in a safe environment. WMHS

Members of The Robotics Group (TRG) of MHI are leading manufacturers, integrators, consultants, and component suppliers of robotic solutions designed specifically for warehousing and distribution applications. TRG conducts education and outreach with the goal of fostering technology adoption in this rapidly changing industry sector. Visit: www.mhi.org/trg