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An anthropomorphic hand arm system using variable stiffness actuation has been developed at DLR. It is aimed to reach its human archetype regarding size, weight and performance. The main focus of our development is put on robustness, dynamic performance and dexterity. Therefore, a paradigm change from impedance controlled, but mechanically stiff joints to(More)
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may(More)
2011 In memory of my great-great-grandfather Carl Heinrich Främbs who was expelled from ETH in the Bolley incident on July 31 st , 1864. ii Acknowledgments First of all, I would like to thank Roland Siegwart for having me as a PhD student over the past four years and for providing the extremely inspiring en-viroment and all the necessary resources that made(More)
Whereas short-term memory lasts from minutes to hours, long-term memory (LTM) can last for days or even an entire lifetime. LTM generally forms after spaced repeated training sessions and involves the regulation of gene expression, thereby implicating transcription factors in the initial steps of LTM establishment. However, the direct participation of(More)
The paper presents a new energy shaping control design for a class of underactuated Euler-Lagrange systems. Flexible joint robots, Series Elastic Actuators, and Variable Impedance Actuated Robots Albu-Schäffer et al. [2008] belong for example to this class. First, classical PD control with feed-forward compensation is revisited and a novel, straightforward(More)
Robots with joint elasticity find increasing interest in many research areas. A common design goal is to achieve as little mechanical joint damping as possible. To still achieve system damping often control systems are used. Here, we present a model-free approach to achieve damping via exploiting the kinetic to potential energy transformation process of the(More)
Compliant actuators in robotic systems improve robustness against rigid impacts and increase the performance and efficiency of periodic motions such as hitting, jumping and running. However, in the case of rigid impacts, as they can occur during hitting or running, the system behavior is changed compared to free motions which turns the control into a(More)
The elastic energy storage in biologically inspired variable impedance actuators (VIA) offer the capability of executing cyclic and/or explosive multi-degree of freedom (DoF) motions efficiently. This paper studies the generation of cyclic motions for strongly nonlinear underactuated multi-DoF serial robotic arms. By experimental observations of human motor(More)
Anthropomorphic robots that aim to approach human performance agility and efficiency are typically highly redundant not only in their kinematics but also in actuation. Variable-impedance actuators, used to drive many of these devices, are capable of modulating torque and impedance (stiffness and/or damping) simultaneously, continuously, and independently.(More)
The concept of variable stiffness actuation (VSA) for robotic joints promises advantages regarding robustness, energy efficiency, and task adaptability. The VS joints developed at DLR show very low intrinsic damping for efficient energy storage and retrieval whereas the desired damping behavior for task execution needs to be implemented in control. Robotic(More)