Human–robot collaboration is currently one of the frontiers of industrial robot implementation. In parallel, the use of robots and robotic devices is increasing in several fields, substituting humans in “4D”—dull, dirty, dangerous, and delicate—tasks, and such a trend is boosted by the recent need for social distancing. New challenges in safety assessment and verification arise, due to both the closer and closer human–robot interaction, common for the different application domains, and the broadening of user audience, which is now very diverse. The present paper discusses a cross-domain approach towards the definition of step-by-step validation procedures for collaborative robotic applications. To outline the context, the standardization framework is analyzed, especially from the perspective of safety testing and assessment. Afterwards, some testing procedures based on safety skills, developed within the framework of the European project COVR, are discussed and exemplary presented.

The use of collaborative robots in the industrial domain has significantly grown in the last years, allowing humans to operate in the same workspace occupied by robots without any physical barriers. Understandably, the safety of the human operator has been a major concern both for researchers and regulatory bodies. The power and force limited modality of robots is of particular interest in that sense, being used in order to bound the energy of eventual collisions when a close physical interaction with humans is necessary. Such an interaction modality allows the robotic system to operate without the use of barriers, but a measurement of the force and pressure occurring due to a contact must be provided as part of the risk assessment. However, the precise procedure to follow in order to reliably provide such measures is still unclear for users and system integrators willing to self-assess the safety of their own collaborative robotic system. In this work, the repeatability and reliability of such testing procedures and measures are analyzed with an interlaboratory comparison approach, with the aim to establish the degree of variability possibly encountered when performing the same test under slightly different conditions.

With the increasing importance of collaborative robots in industrial manufacturing, their economic efficiency is becoming more and more important. Today, one approach to prevent collaborative robots from injuring humans is to assure that the robot cannot exceed biomechanical limits in the event of an accidental collision or clamping. The ability of the robot to avoid collision forces beyond the limits must be validated with a biofidelic measurement device that mimics the biomechanical behavior of the human. For reliable use, the measurement devices must be attached to a rigid frame. Consequently, the test setup is solely able to simulate the contact dynamics and biomechanical consequences of a clamping contact in which the human body part cannot move. Free collisions that allow the human to move freely reduce the collision forces, but can only be evaluated with such a measurement device. This technical limitation leads to slower robots and thus a loss of productivity. The study presents a method that increases the efficiency of safe collaborative robots by adding a new validation procedure. The presented method incorporates a model-based conversion of measurements that enables safety experts to validate robots in free collisions. Data from experimental tests with a collaborative robot and a biofidelic measurement device show a good fit of the model-based prediction and thus confirm our approach. This new approach has great potential to increase the productivity of collaborative robots, since our method will allow them to move at faster but still safe speeds.

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The original version of the chapter “A New Conversion Method to Evaluate the Hazard Potential of Collaborative Robots in Free Collisions” was previously published as non-open access. This has now been changed to the copyright holder “The Author(s)” and Open Access under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). The chapter and the book have been updated with the change.