Formal model of human erroneous behavior for safety analysis in collaborative robotics

Recent developments in manufacturing technologies, also known as Industry 4.0, seek to build Smart Factories where supply chains and production lines are equipped with a higher level of automation. However, this significant innovation does not entirely eliminate the need for the presence of human operators; on the contrary, it requires them to collaborate with robots and execute hybrid tasks. Thus, creating safe workspaces for human operators is crucial for the future of factories where humans and robots collaborate closely in common workspaces. The uncertainty of human behavior and, consequently, of the actual execution of workflows, pose significant challenges to the safety of collaborative applications. This paper extends our earlier work, a formal verification methodology to analyze the safety of collaborative robotics applications (Askarpour et al. 2017) [1], with a rich non-deterministic formal model of operator behaviors that captures the hazardous situations resulting from human errors. The model allows safety engineers to refine their designs until all plausible erroneous behaviors are considered and mitigated. The solidity of the proposed approach is evaluated on a pair of real-life case studies.