Conference Paper

Optimization and Fail-Safety Analysis of Antagonistic Actuation for pHRI.

DOI: 10.1007/11681120_9 Conference: First European Robotics Symposium 2006, EUROS 2006, Palermo, Italy
Source: DBLP

ABSTRACT In this paper we consider some questions in the design of actuators for physical Human-Robot Interaction (pHRI) under strict
safety requirements in all circumstances, including unexpected impacts and HW/SW failures. We present the design and optimization
of agonistic-antagonistic actuation systems realizing the concept of variable impedance actuation (VIA). With respect to previous
results in the literature, in this paper we consider a realistic physical model of antagonistic systems, and include the analysis
of the effects of cross-coupling between actuators. We show that antagonistic systems compare well with other possible approaches
in terms of the achievable performance while guaranteeing limited risks of impacts. Antagonistic actuation systems however
are more complex in both hardware and software than other schemes. Issues are therefore raised, as to fault tolerance and
fail safety of different actuation schemes. In this paper, we analyze these issues and show that the antagonistic implementation
of the VIA concept fares very well under these regards also.

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