Mobile robots – whether it be automated guided vehicle (AGV) systems or autonomous mobile robots (AMRs) – are playing an increasing important role in mobile intralogistics because they significantly increase automation and efficiency in warehouses, production facilities and distribution centers. They general share their operating area with people. Special requirements on their design are therefore needed to ensure the safety of people, machinery and their environment. Olaf Zbikowski, Market Product Manager Industrial Safety at SICK Vertriebs-GmbH explains what safety aspects have to be taken into consideration so that operators of AGVs and the like are truly on the safe side.
Identifying, assessing and minimizing risks: designing safe mobile robots
When designing and constructing AGVs and mobile robots, manufacturers need to observe a whole bunch of current requirements and safety aspects. "At the same time, operators need to be able to rely at initial commissioning, during productive operation and when carrying out maintenance and repairs on the safety equipment of the vehicles, which – not least for liability reasons – are up-to-date with regard to the technology and the legal and normative requirements," explains Olaf Zbikowski. "It is therefore necessary in the early project planning phase of AGV and AMR applications to identify risks, assess them, and take possible protective measures into consideration in the design from the outset."
Risk assessment identifies hazards and possible safety measures
The safety specialist from SICK is referring here to the basis for the safe design of AGVs and AMRs: the risk assessment. It is prescribed both by the Machinery Directive 2006/42/EC (implemented in Germany in the ninth ordinance of the Product Safety Act) and, from January 20, 2027 by the Machinery Regulation (EU) 2023/1230. "This means", according to Olaf Zbikowski, "that the identification of hazards, the assessment and evaluation of safety risks, and the derivation of suitable safety measures for risk reduction and ideally risk prevention are essential for the development of safe mobile robots, AGVs, AGV systems and AMRs – including documenting the related processes and results."
Three steps to a safe design
Safety functions depend on vehicles, applications and operating environment
When selecting safety functions, various characteristics of the AGV and AMR need to be taken into consideration, e.g., the braking and stopping behavior, special aspects of the environment such as ambient light or contamination, application-specific circumstances such as mixed operation or the condition of the route, as well as foreseeable misuse such as persons riding along on the vehicle. "In principle, a variety of safety functions for risk reduction can be implemented," and Olaf Zbikowski lists a few options: "initiating a stop and preventing an automatic restart, differentiating between man and material when entering or exiting a hazardous area in order to bypass safety functions there, or monitoring machine parameters such as speed, position or force."