The vision of seamless human-robot interaction in our everyday life that allows for tight cooperation between human and robot has not become reality yet. Up to now, state-of-the-art industrial robots played the most important role in real-world applications and more advanced, highly sensorized robots were usually kept in lab environments and remained in a prototypical stadium. Various factors like low robustness and the lack of computing power were large hurdles in realizing robotic systems for highly demanding tasks in e.g. domestic environments or as robotic co-workers. Furthermore, limited perception and task planning capabilities are still an issue. However, the recent increase in technology maturity finally made it possible to realize systems of high integration, advanced sensorial capabilities and enhanced power to cross this barrier and merge living spaces of humans and robot workspaces to at least a certain extent. In addition, the increasing effort various companies have invested to realize first commercial service robotics products has made it necessary to properly address one of the most fundamental questions of Human-Robot Interaction: How to ensure safety in human-robot coexistence? Although the vision of coexistence itself has always been present, very little effort has been made to actually enforce safety requirements, or to define safety standards up to now. In this dissertation, the essential question about the necessary requirements for a safe robot is addressed in depth and from various perspectives. The approach taken here focuses on the biomechanical level of injury assessment, addressing the physical evaluation of robot-human impacts and the definition of the major factors that affect injuries during various worst-case scenarios. This assessment is the basis for the design and exploration of various measures to improve the safety in human-robot interaction. They range from control schemes for collision detection, and reaction, to the investigation of novel joint designs. An in-depth analysis of their contribution to safety in human-robot coexistence is carried out. In addition to this “in-contact” treatment of human-robot interaction, the thesis proposes and discusses real-time collision avoidance methods, i.e. how to design pre-collision strategies to prevent unintended contact. An additional major outcome of this thesis is the development of a concept for a robotic co-worker and its experimental verification in an industrially relevant real-world scenario. In this context, a control architecture that enables a behavior based access to the robot and provides an easy to parameterize interface to the safety capabilities of the robot was developed. In addition, the architecture was applied in various other applications that deal with physical Human-Robot Interaction. Generally, all aspects discussed in this thesis are fully supported by a variety of experiments and cross-verifications, leading to strong conclusions in this sensitive and immanently important topic.
展开▼
