In this paper we present a method to calibrate the surface EMG signal-to-force-relationship online. For this, a simple biomechanical model composed of bones and muscles is used. The calibration is based on an online optimization algorithm where the error between the movement of the human and the movement computed with the biomechanical model is minimized. The proposed method will be part of a control system for an exoskeleton robot that should aid the wearer in everyday-life situations like walking, standing up and sitting down. In contrast to existing methods for the calculation of the EMG signal-to-force-relationship, we are not interested in the exact force values of every single muscle, but our model groups some muscles together and uses the EMG signal of one of those muscles as a representative for the group to simplify calculations. The performance of the presented method was investigated on the leg movement in sagittal plane without contact to the environment.

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In this paper, demographic change and ageing societies are identified as potential drivers for the development and implementation of pervasive technologies in our environment. Computers and Microsystems have become smaller and cheaper and become a part of our life and society. Wearable Robots, advanced prosthetics and sensor implants even aim at making human beings part of those developing cyber environments. We think that strategically guided and joint research has to be done and therefore give an overview of the subject and show that advanced BIM and structured environments play a role as core technology in efficiently deploying and managing pervasive computing and assistive environments on city scale.

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A gravity balancing lower extremity exoskeleton is a simple mechanical device composed of rigid links, joints and springs, which is adjustable to the geo-metry and inertia of the leg of a human subject wearing it. This passive exoskeleton does not use any motors or controllers, yet can still unload the human leg joints of the gravity load over the full range of motion of the leg. The underlying principle of gravity balancing consists of two steps: Locate the combined system center of mass of the human leg and the exoskeleton, Add springs to the exoskeleton, one between the cen-ter of mass of the combined system and the fixed frame representing the trunk, the others within the links of the exoskeleton so that the potential energy of the combined system is invariant with configuration of the leg. Additionally, parameters of the exoskeleton can be changed to achieve a pres-cribed level of par-tial balancing, between 0-gravity and 1-gravity. The goals of this paper are as fol-lows: briefly review the theory for gravity balancing and present laboratory prototypes of gravity ba-lanced machines, describe the design of a lower extremity exoskeleton that was fabricated using this prin-ciple, and show the perfor-mance of the exoskeleton on both healthy human subjects and a stroke patient by comparison of leg muscle EMG recordings, joint range of motion, and measured joint torques. These results strongly suggest that human joints can be unloaded from gravity using these exoskeletons and the human joint range of motion can be significantly increased. Potential applications of gravity balancing exo-skeletons include:gait training of stroke patients, characterization of long-term effects of zero gravity on the human musculature, human performance augmentation during assembly tasks.

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This paper deals with the stable walking of biped robots. The presented control algorithm enables a biped to perform stable walking without using any precomputed trajectories. The algorithm merges gait trajectory generation and control, and can be used for global control, for local control along an existing trajectory as well as for online computation of gait trajectories for stable walking. The inputs for the algorithm are a few parameters such as walking speed and step size. The performance of the algorithm is demonstrated by simulation.

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A robot, CWRU Robot V (Ajax) has been constructed based on the death head cockroach, Blaberus discoidalis. In an attempt to further take advantage of the neuromechanics of the animal, actuators with muscle-like properties have been employed that demonstrate a superior force to weight ratio over conventional actuation devices. Although it is not feasible to capture the entire range of motion displayed by the animal (seven degrees of freedom per leg), research has shown that twenty-four degrees of freedom provide a sufficiently close approximation for agile walking and climbing. The fifteen kilogram robot has an offboard power source and control system. Preliminary tests show that it is capable of maintaining stance and lifting significant payloads, as well as rough, open-loop walking.

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