72 research outputs found
Hierarchical Task-Priority Control for Human-Robot Co-manipulation
The extensive distribution of collaborative robots in indus- trial workplaces allows human operators to decrease the weight and the repetitiveness of their activities. In order to facilitate the role of the human worker during the interaction with these robots, innovative con- trol paradigms, enabling an intuitive human-robot collaborative manipu- lation, are needed. In this work, a dynamic and hierarchical task-priority control framework is proposed, leveraging a physical interaction with a redundant robot manipulator through a force sensor. The foremost objec- tive of this approach is to exploit the non-trivial null-space of the redun- dant robot to increase the performance of the co-manipulation and, con- sequently, its effectiveness. A comparison between the proposed method- ology and a standard admittance control scheme is carried out within an industrial use case study consisting of a human operator interacting with a KUKA LBR iiwa arm
Hybrid visual servoing with hierarchical task composition for aerial manipulation
© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.In this paper a hybrid visual servoing with a hierarchical task-composition control framework is described for aerial manipulation, i.e. for the control of an aerial vehicle endowed with a robot arm. The proposed approach suitably combines into a unique hybrid-control framework the main benefits of both image-based and position-based control schemes. Moreover, the underactuation of the aerial vehicle has been explicitly taken into account in a general formulation, together with a dynamic smooth activation mechanism. Both simulation case studies and experiments are presented to demonstrate the performance of the proposed technique.Peer ReviewedPostprint (author's final draft
Active Disturbance Rejection Control for the Robust Flight of a Passively Tilted Hexarotor
This paper presents a robust control strategy for controlling the flight of a passively (fixed) tilted hexarotor unmanned aerial vehicle (UAV). The proposed controller is based on a robust extended-state observer to estimate and reject internal dynamics and external disturbances at run-time. Both stability and convergence of the observer are proved using Lyapunov-based perturbation theory and an ultimate bound approach. Such a controller is implemented within a highly realistic simulation environment that includes physics motors, devising an almost transparent behaviour with respect to the real UAV. The controller is tested for flying under normal conditions and in the presence of different types of disturbances showing successful results. Furthermore, the proposed control system is compared against another robust control approach, presenting a better performance regarding the attenuation of the error signals
Lysosomal dysfunction disrupts presynaptic maintenance and restoration of presynaptic function prevents neurodegeneration in lysosomal storage diseases
Lysosomal storage disorders (LSDs) are inherited diseases characterized by lysosomal dysfunction and often showing a neurodegenerative course. There is no cure to treat the central nervous system in LSDs. Moreover, the mechanisms driving neuronal degeneration in these pathological conditions remain largely unknown. By studying mouse models of LSDs, we found that neurodegeneration develops progressively with profound alterations in presynaptic structure and function. In these models, impaired lysosomal activity causes massive perikaryal accumulation of insoluble α-synuclein and increased proteasomal degradation of cysteine string protein α (CSPα). As a result, the availability of both α-synuclein and CSPα at nerve terminals strongly decreases, thus inhibiting soluble NSF attachment receptor (SNARE) complex assembly and synaptic vesicle recycling. Aberrant presynaptic SNARE phenotype is recapitulated in mice with genetic ablation of one allele of both CSPα and α-synuclein. The overexpression of CSPα in the brain of a mouse model of mucopolysaccharidosis type IIIA, a severe form of LSD, efficiently re-established SNARE complex assembly, thereby ameliorating presynaptic function, attenuating neurodegenerative signs, and prolonging survival. Our data show that neurodegenerative processes associated with lysosomal dysfunction may be presynaptically initiated by a concomitant reduction in α-synuclein and CSPα levels at nerve terminals. They also demonstrate that neurodegeneration in LSDs can be slowed down by re-establishing presynaptic functions, thus identifying synapse maintenance as a novel potentially druggable target for brain treatment in LSDs
Natural treatments for erectile dysfunction: A focus on mobile health applications
To the Editor,
Erectile dysfunction (ED) is defined as the persistent inability to achieve or maintain penile erection sufficient for satisfactory sexual performance. ED represents one of the most important male sexual dysfunctions with a prevalence of 52% and affecting more than 150 million men worldwide (estimated to be 322 million worldwide for 2025) [...
A comprehensive map of CNS transduction by eight recombinant adeno-associated virus serotypes upon cerebrospinal fluid administration in pigs
Cerebrospinal fluid administration of recombinant adeno-associated viral (rAAV) vectors has been demonstrated to be effective in delivering therapeutic genes to the central nervous system (CNS) in different disease animal models. However, a quantitative and qualitative analysis of transduction patterns of the most promising rAAV serotypes for brain targeting in large animal models is missing. Here, we characterize distribution, transduction efficiency, and cellular targeting of rAAV serotypes 1, 2, 5, 7, 9, rh.10, rh.39, and rh.43 delivered into the cisterna magna of wild-type pigs. rAAV9 showed the highest transduction efficiency and the widest distribution capability among the vectors tested. Moreover, rAAV9 robustly transduced both glia and neurons, including the motor neurons of the spinal cord. Relevant cell transduction specificity of the glia was observed after rAAV1 and rAAV7 delivery. rAAV7 also displayed a specific tropism to Purkinje cells. Evaluation of biochemical and hematological markers suggested that all rAAV serotypes tested were well tolerated. This study provides a comprehensive CNS transduction map in a useful preclinical large animal model enabling the selection of potentially clinically transferable rAAV serotypes based on disease specificity. Therefore, our data are instrumental for the clinical evaluation of these rAAV vectors in human neurodegenerative diseases
Nonprehensile Manipulation of Deformable Objects: Achievements and Perspectives from the RobDyMan Project
International audienceThe goal of this work is to disseminate the results achieved so far within the RODYMAN project related to planning and control strategies for robotic nonprehensile manipulation. The project aims at advancing the state of the art of nonprehensile dynamic manipulation of rigid and deformable objects to future enhance the possibility of employing robots in anthropic environments. The final demonstrator of the RODYMAN project will be an autonomous pizza maker. This article is a milestone to highlight the lessons learned so far and pave the way towards future research directions and critical discussions
Iron homeostasis alterations and erectile dysfunction: A new issue in erectile disfunction treatment?
To the Editor, Erectile dysfunction (ED) is one of the most prevalent conditions affecting men globally, with significant psychological and social consequences. The prevalence varies across different populations, and it is estimated around 50% in men aged between 40 to 70. The etiology of ED is multifactorial, involving a complex crosstalk between psychological, hormonal, neurogenic, vascular, and structural factors. Recently, the role of iron homeostasis (IH) is emerging. [...
Perceptions and attitudes toward the use of telemedicine for the postoperative outpatient urological care during the COVID-19 pandemic in an Academic Hospital in Southern Italy
Introduction: Telemedicine is a most used tools in various medical and surgical scenarios. The aim of the present study was to explore attitudes and perceptions by urologic patients toward the use of telemedicine in the context of patient-physicians communication during the post-operative follow-up in a large academic tertiary urology referral department in Italy. Materials and methods: An anonymous questionnaire consisting of 15 multiple choice questions was designed including three sections: respondents' demographics, attitudes, and perceptions towards the use of telemedicine. Invitations to participate to this anonymous questionnaire was given to outpatients attended at Urology Department, University of Naples Federico II. Results: In total 697 responses were received (participation rate 73%). The frequency of telemedicine use was described as frequently, occasional, rarely, and never by 41.6%, 30.4%, 15.1%, and 12.6% of respondents, respectively. WhatsApp messenger used by 59.5% of respondents and telephone call (34.3%) were the most common type of tools. Satisfaction in using telemedicine was reported as very satisfied, satisfied, neutral, dissatisfied, and very dissatisfied by 39.6%,41.4%,10%,7% and 2% of respondents respectively. Overall, 43.7%% of participants individuated limited interaction and risk of misdiagnosis as the major limit of telemedicine. Conclusions: Telemedicine represents the future of medical practice due to several benefits as well as convenience, increased access to care and decreased healthcare costs
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