Digital technologies for the design of human-robot collaborative cells

The growing demand for the customization of products is renewing the efforts of industries in developing systems that are either optimal for a specific product or can rapidly adapt to sudden changes in the production mix. For this reason, companies are showing an increasing interest in using Digital Twins (DT), a technology relying on Cyber-Physical Systems (CPS) that was firstly introduced some years before the outburst of the industry 4.0 paradigm. Today, the adoption of DTs is significantly favored by all the enabling technologies characterizing industry 4.0. As far as the research is concerned, most of the works in the literature are currently focusing on digital twins dealing with a dynamic environment in the production chain, while less attention is paid to the optimal layout design before operation. Within this framework, this work presents a general overview of the most recent technologies in the field of Human-Robot Collaboration (HRC), highlighting their main characteristics and framing them according to the stage in which they are developed, be it pre-deployment or execution. In addition, with regard to the pre-deployment phase, a simulation-guided framework, based on two different optimizers that account for the nature of the variables under exam, is proposed as a way to find the most suitable layout of a collaborative working cell in a static production environment. In such environments, the space and the allocation of tasks between humans and robots is of paramount importance in order to realize a Human-centered Cyber Physical System (HCPS).