Optimal handling of inherent compliance of flexible link manipulators for improved safetyproductively balance in human-robot collabora

The economic attractiveness of collaborative robots, or cobots, is still limited given their restricted allowed working speeds, required to guarantee safety towards the human operator. A relevant way to improve the balance between safety and productivity is to lower the cobot’s weight, as the impact at a collision is not only related to the robot's speed, but also to its mass. While for conventional robots, link stiffness is maximised to guarantee accurate end-effector tracking, a significant decrease in mass can be obtained by lowering the rigidity of the robot links. The inherent flexibility of these so called flexible link manipulators, however, introduces the need for challenging control approaches to counteract the flexural effects. A complementary approach to improve safety/productivity is to focus on safe control strategies, to guarantee mitigation of unexpected collisions and safe interaction control for desired cooperation. In this project, we aim to advance the state of the art by combining both approaches to boost the usability of collaborative robotics. Moreover, while the link flexibility is in general regarded as a major drawback of a lightweight design, the main innovative aspect of this project lies in investigating how we can take advantage of the link flexibility for formulating safe control strategies for collaborative settings, and subsequently, how the flexible link can be designed to contribute to an improved safety/productivity balance.