SafeNet of Unsafe Devices extending the robot safety in collaborative workspaces

Collaborative workspaces represent the benchmark scenario of contemporary and future industrial robotics, where hybrid production systems and multimodal interactions among human operators and robots in cooperative tasks can foster the flexibility of robotic systems. Physical interactions together with dynamic workspacesharing represent some reference applications in ISO 10218-2, where restrictive conditions for safety are posed at system level, eventually limiting the robot execution speed. With the aim of extending the use of industrial robots in shared environments and allowing the use of generically unsafe sensory and computational components for advanced applications, a methodology called SafeNet is presented. It considers the system as a device at large and applies the concept of functional safety (ISO 13489-1) with a set of architectural procedures and implementations. The safety aspects of structure, reliability and monitoring are addressed by a redundant system of computational nodes distributed over a network. SafeNet systems can be upgraded to candidate for safe Performance Levels.