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Doctoral Research Seminar on "Safety-Aware Hierarchical Passivity-Based Variable Compliance Control for Redundant Manipulators"


Today's Doctoral Research Seminar deals with "Safety-Aware Hierarchical Passivity-Based Variable Compliance Control for Redundant Manipulators" by Youssef Abdelwadoud, TUM. 

Abstract:

In this talk, I will present a hierarchical passivity-based compliance controller that exploits robot redundancy and aims at achieving an impedance behavior with a time-varying stiffness on all the priority levels. Unfortunately, this gives rise to certain control actions that lead to the loss of the safety-critical passivity feature. To deal with this problem, we employ the concept of virtual energy tanks that keep track of the passivity violating energy in the system, ensuring that it remains bounded. This restores the passivity in the system, which guarantees stable interaction with any passive environment. Furthermore, we augment our controller with an additional safety layer, which ensures that the energy injected through the tank into the system remains below a safe limit, defined based on the maximum kinetic energy allowed in the system. Finally, our approach is validated in terms of performance during task execution and safety both in simulations and on real-robot hardware.

The talk will start at 11 am today via zoom, interested participants, please get in touch with Nicolas Berberich.