In this paper we present a method to control a one-legged lower extre-mities orthosis by analyzing the current trajectory performed with the healthy leg and feeding a proper- if necessary phase-shifted — trajectory to the disabled leg encased in the orthosis. For this, a fast and simple modified version of the cross correlation is used. The algorithm works on multiple reference curves by minimizing the error between the reference and the current data by adaptively walking forward through the reference of the healthy leg and reporting back the reference values for the disabled leg. 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. The performance of the presented method was investigated on the leg movement in sagittal plane without contact to unknown obstacles.

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In this paper we present a method to calculate the intended motion of joints in the human body by analysing EMG signals. Those signals are emitted by the muscles attached to the adjoining bones during their activation. With the resulting intended motion a leg orthosis will later be controled in real-time to support disabled people while walking or climbing stairs and help patients suffering from the effects of a stroke in their rehabilitation efforts. To allow a variety of different motions, a human body model with physical properties is developed and synchronized with data recorded from the pose sensors. Computing the intended motion is performed by converting calibrated EMG signals to muscle forces which animate the model. The algorithm was evaluated with experiments showing the calculated intended motion while climbing one step of a stair. The algorithm and the experimental results are both shown.

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This paper describes some micro turbine aspects from the standpoint of potential users. First, some of the pros and the cons of small gas turbines compared to other competing technologies are given. The discussed aspects are mainly focussed on technical advantages and disadvan-tages as it is hard to predict how fast and to what extent the different technologies (including that of mini gas turbines) will mature. Even though the final applications will obviously strongly depend upon the economical benefits that the technology would offer, an economical comparison is not made here. Therefore the comparison made throughout this contribution remains relatively general. Once the pros and the cons are discussed, some potential applications are described. The possible applications are divided into two different categories: power generation for portable devices and vehicle propulsion. For each class of applications some examples are given. Finally, then, some conclusions are drawn.

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The prevalence of neurological diseases such as stro-ke, spinal cord injury and traumatic brain injury is increasing quickly in the industrialised societies. Although the benefit of the use of technology in rehabilitation and neurorehabilitation programs is prov-ed, the presence of mechatronic systems is still very low. This paper proposes a new lower limb exo-skeleton for gait rehabilitation in persons with neurological pathologies. Since potential users have very reduced mobility even to start common daily movements, the control of the exoskeleton has to be intention based. The estimation of the intention of the user is based on hip and knee angle, and the EMG signal is monitored for intention detection, control and neurofeedback aims. A novel approach of the EMG to force conversion in paraplegic patients is also described.

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The animation of human avatars seems very successful; the computer graphics industry shows outstanding results in films everyday, the game industry achieves exploits… Nevertheless, the animation and control processes of such manikins are very painful. It takes days to a specialist to build such animated sequences, and it is not adaptive to any type of modifications. Our main purpose is the virtual human for engineering, especially virtual prototyping. As for this domain of activity, such amounts of time are pro-hibitive. We focus our work on interactive virtual human enabling to drive avatars in real time thanks to motion capture devices. Unfortunately, at the moment the quality of the animations produced is far from the quality obtained by artists in the computer graphics area. We aim at filling the gap. Thus we proposed the architecture given, which distinguishes, and splits the simulation from the control itself. This architecture, which we introduced in, is innovative for the virtual reality domain, and was borrowed from robotics. Global scheme of our system Many problems must be solved to succeed in. All the problems arise because of the dif-ference between the real world, and the simulated world. This divergence takes two main shapes: the difference in terms of the hu-man, and the difference in terms of the environment of both worlds.

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