Safety analysis for a human-friendly manipulator

The DLR Lightweight Robot III (LWR-III) developed at the German Aerospace Center (DLR) is characterized by low inertial properties, torque sensing in each joint, and a load to weight ratio similar to humans. These properties qualify it for applications requiring high mobility and direct interaction with human users or uncertain environments. An essential requirement for such a robot is that it must under no circumstances pose a threat to the human operator. To actually quantify the potential injury risk emanating from the manipulator, impact test were carried out using standard automobile crash-test facilities at the ADAC (German automobile club). Furthermore, we introduce our analysis for soft-tissue injury based on swine experiments with the LWR-III. This paper gives an overview about the variety of investigations necessary to provide a safety analysis of a human-friendly robot based on biomechanical injury results. We believe this paper can provide a guideline for the robotics community for future qualifications of other robots and thus serve as a key component to bring robots in our everyday life.