1,720,962 research outputs found
Development of Methodologies, Mechatronic Solutions and Controls for Upper Body Rehabilitative Robotics
Full text linkL'abstract è presente nell'allegato / the abstract is in the attachmen
Improving SEA Joint Torque Sensing for Enhanced Torque Estimation in Human-Machine Interaction
No full textEstimating human-robot interaction (HRI) in rehabilitative robotics poses challenges from both mechatronics and control standpoints. In this study, the authors introduce a method to tackle non-linear effects impacting Series Elastic Actuator (SEA) mechatronic systems. Achieving an accurate characterization of the SEA system enables improved torque estimation based on spring deformation. By improving torque sensing capabilities, the objective is to enhance HRI assessment for patient evaluation and enable compliant closed-loop control. The adopted method involves experimental testing, subjecting the SEA to mechanical stress under various load conditions. Experiments were conducted to explore SEA characteristics across different load configurations: joint at the bench with no-load, low-medium-high load, and joint assembled on an exoskeleton prototype. Analysis of the data revealed variability in SEA torque estimation errors, with higher loads associated with greater errors. To mitigate these errors and enhance torque estimation, the non-linearities have been characterized using two Fourier series (5th and 8th order) in both no-load and load conditions. Theoretical approaches and experimental results of this SEA characterization methodology will be presented to demonstrate the feasibility of this approach
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A Preliminary Approach to Assessing Scapular Synergies with the FloatEvo Exoskeleton
No full textRobotic rehabilitation is increasingly adopted to enhance intensity and quality of rehabilitative sessions after traumatic events. Exoskeletons, in particular, show promise in delivering precise, intensive, and physiologically relevant physical therapy. Beyond providing movement guidance, these technologies can also be used to monitor and measure patient activity, with a particular focus on human kinematics, such as range of motion and motion synergies. In the context of upper limb rehabilitation, this study presents a preliminary investigation into the FloatEvo capability to monitor scapular rhythm and synergy exclusively through its integrated sensors
Design Improvements to the Float Upper-Limb Exoskeleton Better Mimics the Glenohumeral Complex Kinematics
No full textThe shoulder glenohumeral complex stands out as one of the most complex structures within the human body. Designing a system that can effectively interface with it poses a significant challenge for researchers. In this study, we propose a methodology based on evaluating various metrics to assess the performance of new kinematic solutions for mimicking the glenohumeral complex. The proposed method is demonstrated on an existing design (Float) of an upper-limb exoskeleton. The results show a successful expansion of the reachable workspace and enhancement of the shoulder internal-external rotation. The improvements ensure the necessary range-of-motion for the patient’s natural use of the exoskeleton. Specifically, the existing Eulerian wrist architecture is replaced with a 3-degree-of-freedom RPY wrist to better resemble the glenohumeral shoulder joint complex. This study also explores the trade-offs between these enhancements and the desired system manipulability
Comparative analysis of inverse kinematics methodologies to improve the controllability of rehabilitative robotic devices
No full textThe solution of the inverse kinematics problem in multi-degrees of freedom robots has been tackled, through the last three decades, by several different approaches including analytical, geometrical, differential and numerical methods. All these techniques present their own advantages and drawbacks. However, a guideline on which approach is better to follow, depending on the kind of task to perform and the type of robotic device used, is still missing. In this work, a quantitative comparative analysis of three different inverse kinematics methodologies for the control of rehabilitative robotic devices is proposed, with aim of devising best practices and guidelines for the selection of the most suitable approach. The analyzed methodologies are implemented and numerically tested on two actual devices, specifically an upper-limb exoskeleton and an upper-limb prosthetic arm
Human Exoskeleton Interfaces and Precision Robotic-Human Joint Alignment for Enhanced Upper Limb Rehabilitation
No full textIn the design of a robotic rehabilitative device, the human-machine attachment system plays a crucial role: it is essential to guarantee a correct physiological-robotic joint alignment to avoid exerting abnormal mechanical stress on the limb and to properly mobilize the injured body segment. The purpose of this work is to introduce an innovative patient-exoskeleton interface and positioning system designed to accommodate a wide range of body percentiles. This system aims at ensuring proper patient positioning and at expedite the dressing procedure, providing a user-centric and efficient exoskeleton-wearing experience for both patients and therapists. The new design is based on insights gained from a clinical study involving orthopaedic patients and the Float exoskeleton
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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