The use of autonomous mobile robots (AMRs) to transport materials through industrial buildings is booming. AMRs improve the efficiency of logistics while freeing employees from heavy, monotonous and low-value material-moving tasks. While these robots are designed to navigate safely around people, ongoing changes in the market can leave new users questioning how to ensure a safe installation. And the market’s fast growth has made it difficult for standards organizations to keep up and provide guidance.
If your company is looking into purchasing an AMR or fleet of AMRs, consider these safety tips:
1. Know what you’re buying. AMRs complete their given missions using sensors and software algorithms to maneuver through dynamic environments and avoid obstacles, with some AMRs recomputing their path on the fly. Extensive built-in safety mechanisms allow the robots to navigate collaboratively around human co-workers by slowing down, changing direction, or stopping to avoid collision. These safety features are key to the success of AMRs (the mobile robot itself) and AMR systems (the AMR, or fleet of AMRs—as well as charging stations, load transfer stations, and peripherals such as top modules that are mounted on the robots). Be sure to ask what safety features are included and whether there is an opportunity to add additional features as technology advances.
2. Understand applicable standards, laws and directives. Companies deploying AMRs need to be sure their robots meet existing standards that ensure they operate in a way that does not bring humans into dangerous situations. Fortunately, as installations increase, global standards organizations are updating and developing guidelines for the safe design, manufacture and commissioning of mobile robots. Here’s what is important to know now (see “Applicable Standards For Mobile Robots” below for additional details):
- Standards and laws that are amended for AMRs are under development and planned to be introduced in 2020.
- AMR manufacturers should follow current standards that are developed for logistics applications to ensure a safe AMR and AMR system.
- Safety standards and laws are determined locally by country/region, so deployed AMRs must meet those local standards.
- For global manufacturers using AMRs worldwide, the European standard EN 1525:1997 and the CE mark provide a solid framework when it comes to safety for the AMR, as well as the AMR system. They can be applied to all factories with an amendment to address local aspects. While it is not a requirement to comply to EU laws and standards outside the EU, it makes sense to use these principles to ensure a safe AMR system across all regions.
3. Work closely with manufacturers and integrators—everyone has a part to play:
To truly reap the benefits of AMRs while ensuring workers’ safety, expect to work closely with your AMR manufacturer and integrator.
First, manufacturers need to provide an AMR designed to be commissioned in a safe AMR system, including the environment, charging station, top modules and other peripherals, along with adequate information for integration and operation. The documentation must specify intended use and limitations of the AMR, and CE-mark the AMR according to intended use through compliance to safety standards for automated guided vehicles (AGVs), which is what most of today’s standards are based on. They must also comply with complementary standards to address all risks, and provide integrated safety functions to address hazards expected in the intended use.
Integrators are then responsible for implementing the robot. Because AMRs can be programmed to move throughout a building, factory or warehouse, the integrator who commissions the AMR must anticipate potential safety hazards and program the robot to act appropriately in compliance with safety standards. Commissioning also extends to the top module.
Once the AMR system has been deployed, the end-users are then responsible for setting up and following procedures for operation and maintenance. The end-user must ensure that the intended use and limitations are met, and set up procedures for inspections and maintenance for the AMR system, including warning and markings. The end-user should define safe operating procedures for operators and define training for operators, other staff and visitors for safe operation. Note that in some cases the end-user also acts as the integrator, and is responsible for both of these activities.
4. Reassure your employees: Before installing your AMRs, make sure your employees, especially those who will work beside the robots, know what to expect from the robots. If they understand that your company is doing everything possible to keep them safe—from ensuring the AMRs have proper safety features built in (sensors, software algorithms and AI capabilities) to working with the manufacturer to ensure updated standards are being followed—any concern about safety should quickly dissipate.
With employee safety a top priority for any company, these tips should help provide a safe environment, one that requires you to work closely with your AMR manufacturer and integrator to ensure adherence to evolving standards for an overall safe mobile robot installation. With the boom in installations worldwide, compromising on safety can be a big mistake.
More details on current and emerging safety standards and the European safety guidelines can be found in MiR’s white paper, “Your Guide to Safe Mobile Robot Installation.”
Applicable Standards For Mobile Robots
In Europe, the most applicable standard for AMRs today is EN 1525:1997 (“Safety of Industrial Trucks—Driverless Trucks and Their Systems”). This standard applies to an AGV and its systems, in addition to the commissioning and preparation of the environment in which the robot will be used. A possible successor to EN 1525 as the most applicable standard for AMRs is ISO/FDIS 3691-4: “Driverless Industrial Trucks and Their Systems,” which is scheduled for release in January 2020. ISO/FDIS 3691-4 addresses safety concerns for internal logistics and the hazards related to recompute paths on the fly, which are key aspects of AMRs. The new standard will provide detailed requirements for commissioning mobile robots as well as environment and work-cell design.
In the United States, the American National Standards Institute/Industrial Truck Standards Development Foundation wrote the B56.5-2012 standard to address AGVs. It has the same scope as EN 1525.
Other standards in progress that will likely have impacts on manufacturers, users and integrators of mobile robots in the future include ISO 10218, prRIA 15:08 and prUL 3100, each of which addresses different aspects of AMRs and their implementation.
Ed Mullen is vice president of sales—Americas, Mobile Industrial Robots ApS.