Nikos G. Tsagarakis

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— A new versatile Hydraulically-powered Quadruped robot (HyQ) has been developed to serve as a platform to study not only highly dynamic motions such as running and jumping, but also careful navigation over very rough terrain. HyQ stands 1 meter tall, weighs roughly 90kg and features 12 torque-controlled joints powered by a combination of hydraulic and(More)
— This paper presents a novel whole-body torque-control concept for humanoid walking robots. The presented Whole-Body Motion Control (WBMC) system combines several unique concepts. First, a computationally efficient gravity compensation algorithm for floating-base systems is derived. Second, a novel balancing approach is proposed, which exploits a set of(More)
The incorporation of intrinsic compliance in robotic actuation systems has attracted the attention during recent years due to the considerable benefits which is not possible to achieve with conventional “stiff” actuation systems. However, despite the numerous compliant robots developed, a systematic method for tuning the passive elasticity of(More)
— As recent application domains emerge requiring the employment of robots within unstructured environments, new demands arise requiring more versatile systems which can cope with unpredictable interactions. Recently, compliance has been identified as one of the key features which enables the safe operation of robots interacting with humans and environment.(More)
The basic concepts for exoskeletal systems have been suggested for some time with 21 applications ranging from construction, manufacturing and mining to rescue and emergency services. In recent years, research has been driven by possible uses in medi-23 cal/rehabilitation and military applications. Yet there are still significant barriers to the effective(More)
The significant competitive advantage of hydraulics (high power density, large output force/torque and wide range of speeds) together with the properties of water (low compressibility, high thermal conductivity, low solubility of air, non-flammability and no environmental hazard) make water hydraulic actuation very suitable for systems such as legged(More)
—The research presented in this manuscript aimed to: i) analyze human motion, introducing the kinematic Motion Primitives (kMPs), ii) propose an application of the kMPs to synthesize human-like walking trajectories for the COmpliant huMANoid COMAN. A Principal Component Analysis (PCA) was applied to the whole-body joint trajectories, that were derived from(More)