Modelling and Experimental Evaluation of a Static Balancing Technique for a new Horizontally Mounted 3-UPU Parallel Mechanism

This paper presents the modelling and experimental evaluation of the gravity compensation of a horizontal 3-UPU parallel mechanism. The conventional Newton-Euler method for static analysis and balancing of mechanisms works for serial robots; however, it can become computationally expensive when applied to the analysis of parallel manipulators. To overcome this difficulty, in this paper we propose an approach, based on a Lagrangian method, that is more efficient in terms of computation time. The derivation of the gravity compensation model is based on the analytical computation of the total potential energy of the system at each position of the end-effector. In order to satisfy the gravity compensation condition, the total potential energy of the system should remain constant for all of the manipulator's configurations. Analytical and mechanical gravity compensation is taken into account, and the set of conditions and the system of springs are defined. Finally, employing a virtual reality environment, some experiments are carried out and the reliability and feasibility of the proposed model are evaluated in the presence and absence of the elastic components

Effects of dance therapy on balance, gait and neuro-psychological performances in patients with Parkinson's disease and postural instability

Postural Instability (PI) is a core feature of Parkinson’s Disease (PD) and a major cause of falls and disabilities. Impairment of executive functions has been called as an aggravating factor on motor performances. Dance therapy has been shown effective for improving gait and has been suggested as an alternative rehabilitative method. To evaluate gait performance, spatial-temporal (S-T) gait parameters and cognitive performances in a cohort of patients with PD and PI modifications in balance after a cycle of dance therapy

A comprehensive approach to lung function in bronchiectasis

Background: International guidelines recommend simple spirometry for bronchiectasis patients. However, pulmonary pathophysiology of bronchiectasis is very complex and still poorly understood. Our objective was to characterize lung function in bronchiectasis and identify specific functional sub-groups. Methods: This was a multicenter, prospective, observational study enrolling consecutive adults with bronchiectasis during stable sate. Patients underwent body-plethysmography before and after acute bronchodilation testing, diffusing lung capacity (DLCO) with a 3-year follow up. Air trapping and hyperinflation were a residual volume (RV) > 120%predicted and a total lung capacity>120%predicted. Acute reversibility was: \u394FEV1 6512% and 200 mL from baseline (FEV1rev) and \u394RV 6510% reduction from baseline (RVrev). Sensitivity analyses included different reversibility cutoffs and excluded patients with concomitant asthma or chronic obstructive pulmonary disease. Results: 187 patients were enrolled (median age: 68 years; 29.4% males). Pathophysiological abnormalities often overlapped and were distributed as follows: air trapping (70.2%), impaired DLCO (55.7%), airflow obstruction (41.1%), hyperinflation (15.7%) and restriction (8.0%). 9.7% of patients had normal lung function. RVrev (17.6%) was more frequent than FEV1rev (4.3%). Similar proportions were found after multiple sensitivity analyses. Compared with non-reversible patients, patients with RVrev had more severe obstruction (mean(SD) FEV1%pred: 83.0% (24.4) vs 68.9% (26.2); P = 0.02) and air trapping (RV%pred, 151.9% (26.6) vs 166.2% (39.9); P = 0.028). Conclusions: Spirometry alone does not encompass the variety of pathophysiological characteristics in bronchiectasis. Air trapping and diffusion impairment, not airflow obstruction, represent the most common functional abnormalities. RVrev is related to worse lung function and might be considered in bronchiectasis\u2019 workup and for patients\u2019 functional stratification

Predicting needlestick and sharps injuries in nursing students: Development of the SNNIP scale

© 2020 The Authors. Nursing Open published by John Wiley & Sons Ltd. Aim: To develop an instrument to investigate knowledge and predictive factors of needlestick and sharps injuries (NSIs) in nursing students during clinical placements. Design: Instrument development and cross-sectional study for psychometric testing. Methods: A self-administered instrument including demographic data, injury epidemiology and predictive factors of NSIs was developed between October 2018–January 2019. Content validity was assessed by a panel of experts. The instrument's factor structure and discriminant validity were explored using principal components analysis. The STROBE guidelines were followed. Results: Evidence of content validity was found (S-CVI 0.75; I-CVI 0.50–1.00). A three-factor structure was shown by exploratory factor analysis. Of the 238 participants, 39% had been injured at least once, of which 67.3% in the second year. Higher perceptions of “personal exposure” (4.06, SD 3.78) were reported by third-year students. Higher scores for “perceived benefits” of preventive behaviours (13.6, SD 1.46) were reported by second-year students

\u201cChanges\u201d: An Immersive Spatial Audio Project Based on Low-Cost Open Tools

An immersive multimedia project, namely "Changes", is presented to show the potential and effectiveness of an immersive experience based on spatial audio narration. The experience allows the listener to live an experience that begins by immersing him in a natural environment, then taking him to a war scenario and then back again to nature. The purpose of the paper is to explain the importance of the audio component in a multi-sensory storytelling.Also, the will of the experience is to use free or low cost tools, in order that other people can easily take up the work and continue it or modify it

Modelling and Experimental Evaluation of a Static Balancing Technique for a New Horizontally Mounted 3-UPU Parallel Mechanism

This paper presents the modelling and experimental evaluation of the gravity compensation of a horizontal 3‐UPU parallel mechanism. The conventional Newton‐Euler method for static analysis and balancing of mechanisms works for serial robots; however, it can become computationally expensive when applied to the analysis of parallel manipulators. To overcome this difficulty, in this paper we propose an approach, based on a Lagrangian method, that is more efficient in terms of computation time. The derivation of the gravity compensation model is based on the analytical computation of the total potential energy of the system at each position of the end‐effector. In order to satisfy the gravity compensation condition, the total potential energy of the system should remain constant for all of the manipulator’s configurations. Analytical and mechanical gravity compensation is taken into account, and the set of conditions and the system of springs are defined. Finally, employing a virtual reality environment, some experiments are carried out and the reliability and feasibility of the proposed model are evaluated in the presence and absence of the elastic components

Design and kinematic optimization of a novel underactuated robotic hand exoskeleton

This study presents the design and the kinematic optimization of a novel, underactuated, linkage-based robotic hand exoskeleton to assist users performing grasping tasks. The device has been designed to apply only normal forces to the finger phalanges during flexion/extension of the fingers, while providing automatic adaptability for different finger sizes. Thus, the easiness of the attachment to the user’s fingers and better comfort have been ensured. The analyses of the device kinematic pose, statics and stability of grasp have been performed. These analyses have been used to optimize the link lengths of the mechanism, ensuring that a reasonable range of motion is satisfied while maximizing the force transmission on the finger joints. Finally, the usability of a prototype with multiple fingers has been tested during grasping tasks with different objects

A dynamically reconfigurable stereoscopic/panoramic vision mobile robot head controlled from a virtual environment

We have built a mobile robotic platform that features an Active Robotic Head (ARH) with two high-resolution cameras that can be switched during robot operation between two configurations that produce respectively panoramic and stereoscopic images. Image disparity is used for improving the quality of the texture. The robot head switches dynamically, based on robot operation between the stereoscopic configuration and the panoramic configuration