by Declan Staunton
Autonomous mobile robots (AMRs) lend themselves to modern manufacturing facilities with their ability to self-navigate through dynamic environments, transporting payloads between workstations without compromising the health and safety of nearby workers. To ensure safe operation, developers, regulators, and users must collaborate to address both technical and ethical challenges.
Previous blogs in the series have spoken to the technology advancements within mobile robotics. Today we will explore relevant regulations and standards necessary for the design, development, and safe deployment of these innovative mobile robots in contemporary manufacturing settings.
The new EU Machinery Regulation 2023/1230[i], published in the Official Journal of the EU on 29 June 2023, provides requirements for emerging technologies such as Artificial Intelligence (AI), Internet of Things (IOT) and Robotics. It has defined the term ‘autonomous mobile machinery’ as mobile machinery that operates in an autonomous mode, where all essential safety functions are maintained during normal operation.
The new regulation will repeal the Machinery Directive 2006/42/EC and becomes legally binding in all EU states on 20 January 2027. To comply, manufacturers must demonstrate product conformity with harmonized standards.
There are three types of standards: Type A – Basic Safety Standard (Principles of Design), Type B – Generic Safety Standard (Particular Safety Aspects) and Type C – Machinery Safety Standard (Safety Guidelines).
Figure 1: Overview of the 3 types of Standards for EU Machinery Regulations
The initial step in the compliance process is to determine the risk associated with operating the AMR in an enclosed space with obstacles in the vicinity. The manufacturer must perform a risk assessment to identify potential hazards and hazardous situations and suggest potential risk reduction measures.
The Type A standard EN ISO 12100:2010[ii], “Safety of Machinery – General principles for design – risk assessment and risk reduction,” provides guidance in the principles and methodology for achieving safety in the design of machinery.
For guidance on hazards associated with AMR, Annex B of EN ISO 3691-4:2023[iii] provides a list of significant mechanical, electrical, thermal, and ergonomic hazards. This regulation outlines specific safety requirements and verification methods for driverless trucks, including Automated Guided Vehicles (AGVs), AMRs and Automated Guided Carts (AGCs).
Sub-Clause 4 of EN ISO 3691-4:2023 details the safety requirements and protective measures necessary for these autonomous mobile machines, including details about modes of operation, detection of person in the path, speed control, braking system, electrical systems, and automatic battery charging.
Figure 2 illustrates the relationship between protective measures and the hazard situations in which they apply. There are five performance levels, with PLa offering a minimal contribution to risk reduction, and PLe providing the highest contribution to risk reduction.
Figure 2: Visual Representation of ISO 3691-4:2023 Subclause 4.11 – Table 3 (Safety-Related parts of the control system)
Here’s an example of what it might look like to comply with the harmonized standards under EU Machinery Regulation 2023/1230.
The hazard of colliding with a person can be mitigated by detecting a person in the path of the AMR. Typical protective measures for detecting a person in the path include Electro-Sensitive Protective Equipment (ESPE) devices such as a 2D laser scanner or 3D Time of Flight (ToF) sensors.
AMRs are equipped with braking systems that, upon interruption of the power supply, ensure fail-safe operation. The braking system shall automatically activate upon detection of excessive speed and detection of person in the path.
The implementation of these protective measures, particularly the safety-related components of the control system, must meet the specified Performance Level (PL) in accordance with ISO 13849-1:2023[iv]. The safety-related parts of the braking control system on the AMR requires minimum performance level D (PLd) according to ISO 13849-1.
The deployment of AMRs in modern manufacturing represents an evolutionary leap for flexible manufacturing systems. Their autonomous capabilities and adaptability to dynamic environments can enhance productivity and provide a safe working environment for human workers.
However, the integration of these technologies requires strict adherence to regulatory standards to ensure their safe and effective operation. The recent introduction of the EU Machinery Regulation 2023/1230 and technology advancement underscores the importance of mindful design, codifying risk assessment and reduction as part of the product development process.
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