## 1 Introduction and State of the Art  
Over the last three centuries, manufacturing has radically evolved through the industrial revolutions. The manufacturing has moved from hand production to high automated production through the replacement of humans by machines. During the last decade, the technological advances have boosted the fourth industrial revolution (_Industry 4.0_) [1,2]. Internet of Things (IoT), cloud computing, big data, robotics and Artificial Intelligence (AI) are the main involved technologies in the Industry 4.0 that aims at developing smart manufacturing for mass production by the provision of Cyber-Physical Production Systems (CPPS) [3,4]. Industry 4.0 is only focusing on the efficiency of the process ignoring the human role and capability that are crucial for a lot of production processes [5], especially in the context of the new mass customisation trend. To respond to the multiple types of market demands, the manufacturing requires production lines to be adaptive, intelligent, and flexible for rapidly changing production methods and products. In such a context, the role of machines and humans has changed and evolved again. Nowadays, we are living a new transition from the fourth to the fifth industrial revolution (Industry 5.0) [6; 7]. As defined by the Directorate-General for Research and Innovation (European Commission) [8] _\"Industry 5.0 recognises the power of industry to achieve societal goals beyond jobs and growth to become a resilient provider of prosperity, by making production respect the boundaries of our planet and placing the well-being of the industry worker at the centre of the production process.\"_. Industry 5.0 is based on three pillars: Resilience--robustness in industrial production also in times of crisis; Sustainability--low energy consumption and greenhouse emissions by using and recycling natural resources; Human-centric--human is the centre of production process. The human-centric pillar is mainly based on Human-Robot Collaboration (HRC), human and collaborative robot (cobot) work together sharing tasks and spaces without separation fences [9]. The absence of physical separation is the main issue for safely HRC application, especially for mobile robots and automated mobile cobots (AMCs) that can potentially navigate all around the factory. There are a lot of safety standards and technical specifications for industrial robotics but almost all of them are not focused on the safety collaboration between human and robot. ISO 10218-1/2:2011 [10; 11] and ISO/TS 15066:2016 [12] define four basic levels of collaboration related to fixed cobot; moreover, ISO/TS 15066:2016 provides thresholds for human-robot contact related to the \"quasi-static\" and the \"transient\" contact. ISO 3691-4:2020 [13] defines safety requirements for driverless industrial trucks, i.e., Automated Guided Vehicles (AGVs) and Autonomous Mobile Robots (AMRs). That regulation framework can no longer be applied for all the collaborations between humans and mobile manipulators,i.e., Autonomous Mobile Manipulator (AMM) as well as Autonomous Mobile Cobot (AMC), since the current standards do not address the new risks related to the integration of the two systems (i.e., mobile robot and manipulator). The full HRC implementation requires new Standards and new approaches for both cobot and workplace design [14] by using dedicated methods to assess application impact and safety [15]. Industry 5.0 is taking factory to the synergistic coexistence of classic and HRC workplaces as well as AMM and AMC. The factory is an open space with humans and automated systems freely moving before, during, and after task execution. A complete definition of a such system, starting from its requirements up to its behaviour, requires the usage of multiple and heterogeneous models to catch all involved aspects as, for example, performances, safety, data monitoring, and requirement traceability during the life-cycle.