SAFER-HRC: Safety Analysis Through Formal vERification in Human-Robot Collaboration

Abstract

Whereas in classic robotic applications there is a clear segregation between robots and operators, novel robotic and cyber-physical systems have evolved in size and functionality to include the collaboration with human operators within common workspaces. This new application field, often referred to as Human-Robot Collaboration (HRC), raises new challenges to guarantee system safety, due to the presence of operators. We present an innovative methodology, called SAFER-HRC, centered around our logic language TRIO and the companion bounded satisfiability checker Zot, to assess the safety risks in an HRC application. The methodology starts from a generic modular model and customizes it for the target system; it then analyses hazards according to known standards, to study the safety of the collaborative environment.

Modeling Operator Behavior in the Safety Analysis of Collaborative Robotic Applications

“…The SAFER-HRC methodology [3,4] hinges on a formal model of HRC applications that relies on a discrete notion of time, and on finite discretizations of the notion of space and of the scalar properties of systems-e.g., velocity. Let us first provide some background on the techniques on which the model is based.…”

“…In this paper we extend the SAFER-HRC methodology introduced in [3,4] for the assessment of the safety of Human-Robot Collaborative (HRC) applications, by improving the formal model of operators on which the methodology relies.…”

“…In [3,4] we formalized collaborative systems to verify the physical safety of human operators. We used a task-analytic approach that models collaborative systems in terms of three main modules-Operator, Robot and Layout-and breaks down tasks into atomic actions.…”

Safety Controller Synthesis for Collaborative Robots

“…Askarpour et al [20] discuss a discrete-event formalisation of a work cell in the linear-time temporal language TRIO. Actions are specified as pre/inv /post-triples (with a safety inv ariant) for contract-based reasoning with the SAT solver Zot.…”

Development of an anthropomorphic mobile manipulator with human, machine and environment interaction

“…The conjugation of the designed robot's vision sensor, ultrasound sensor information and a LIDAR sensor must guarantee verification of this condition. Power and Force Limiting (PFL) regards collaboration where psychical interaction between a robot and an operator occurs [20]. The risk reduction is related to a suitable robot design, suited limit criteria for contact events and design and control choices to respect said criteria, reducing the kinetic energy in an eventual impact during human interaction.…”