Partial discharge (PD) measurements provide valuable information for assessing the condition of high voltage (HV) insulation systems, contributing to their quality assurance. Different PD measuring techniques have been developed in the last years specially designed to perform on-line measurements. Non-conventional PD methods operating in high frequency bands are usually used when this type of tests are carried out. In PD measurements the signal acquisition, the subsequent signal processing and the capability to obtain an accurate diagnosis are conditioned by the selection of a suitable detection technique and by the implementation of effective signal processing tools. This paper proposes an optimized electromagnetic detection method based on the combined use of wideband PD sensors for measurements performed in the HF and UHF frequency ranges, together with the implementation of powerful processing tools. The effectiveness of the measuring techniques proposed is demonstrated through an example, where several PD sources are measured simultaneously in a HV installation consisting of a cable system connected by a plug-in terminal to a gas insulated substation (GIS) compartment.
Abstract-This work is focused on obtaining efficient human hand models that are suitable for manipulation tasks. A 24 DoF kinematic model of the human hand is defined to realistic movements. This model is based on the human skeleton. Dynamic and Static constraints have been included in order to improve the movement realism. Two simplified hand models with 9 and 6 DoF have been developed according to the constraints predefined. These simplified models involve some errors in reconstructing the hand posture. These errors are calculated with respect to the 24 DoF model and evaluated according to the hand gestures. Finally, some criteria are defined to select the hand description best suited to the features of the manipulation task.
Flexible soft exoskeletons, so-called exosuits, are robotic devices that interact with their users to assist or enhance muscle performance. Their lightweight design and lack of rigid parts allow assisting the user's natural motion without any constraints. They are thereby valuable in carrying out daily labour tasks and performing active stances of rehabilitation. Nonetheless, the usage of these devices in long-term applications demands anatomically adaptive designs and mechanisms to tackle textile artefacts and discrepancies in the human constitution. The soft exoskeleton described in this article is a textile-wearable design that assists shoulder and elbow flexion. The cable-driven actuation is embedded in a jacket by using several textiles and deformable parts. The inconveniences of using textile such as slipping, dampening, and pressure sores are tackled by combining textile layers with force-compliant sewing. The design also includes pieces for cable guidance, anchoring and support. These parts employ different tailoring methods so as to ease fabrication, wearing and cleaning. The motors and electronics, whose design is compatible with textiles too, are placed in a backpack. This configuration reduces forces from loads in motion and weight on the arm. Finally, the last part of the document discusses the preliminary results that have been obtained from four subjects who have worn the device.
This work focuses on obtaining realistic human hand models that are suitable for manipulation tasks. A 24 degrees of freedom (DoF) kinematic model of the human hand is defined. The model reasonably satisfies realism requirements in simulation and movement. To achieve realism, intra- and inter-finger constraints are obtained. The design of the hand model with 24 DoF is based upon a morphological, physiological and anatomical study of the human hand. The model is used to develop a gesture recognition procedure that uses principal components analysis (PCA) and discriminant functions. Two simplified hand descriptions (nine and six DoF) have been developed in accordance with the constraints obtained previously. The accuracy of the simplified models is almost 5% for the nine DoF hand description and 10% for the six DoF hand description. Finally, some criteria are defined by which to select the hand description best suited to the features of the manipulation task.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.