Position Control of a 3-CPU Spherical Parallel Manipulator

The paper presents the first experimental results on the control of a prototypal robot designed for the orientation of parts or tools. The innovative machine is a spherical parallel manipulator actuated by 3 linear motors; several position control schemes have been tested and compared with the final aim of designing an interaction controller. The relative simplicity of machine kinematics allowed to test algorithms requiring the closed-loop evaluation of both inverse and direct kinematics; the compensation of gravitational terms has been experimented as well

Adaptive Obstacle Avoidance for a Class of Collaborative Robots

In a human–robot collaboration scenario, operator safety is the main problem and must be guaranteed under all conditions. Collision avoidance control techniques are essential to improve operator safety and robot flexibility by preventing impacts that can occur between the robot and humans or with objects inadvertently left within the operational workspace. On this basis, collision avoidance algorithms for moving obstacles are presented in this paper: inspired by algorithms already developed by the authors for planar manipulators, algorithms are adapted for the 6-DOF collaborative manipulators by Universal Robots, and some new contributions are introduced. First, in this work, the safety region wrapping each link of the manipulator assumes a cylindrical shape whose radius varies according to the speed of the colliding obstacle, so that dynamical obstacles are avoided with increased safety regions in order to reduce the risk, whereas fixed obstacles allow us to use smaller safety regions, facilitating the motion of the robot. In addition, three different modalities for the collision avoidance control law are proposed, which differ in the type of motion admitted for the perturbation of the end-effector: the general mode allows for a 6-DOF perturbation, but restrictions can be imposed on the orientation part of the avoidance motion using 4-DOF or 3-DOF modes. In order to demonstrate the effectiveness of the control strategy, simulations with dynamic and fixed obstacles are presented and discussed. Simulations are also used to estimate the required computational effort in order to verify the transferability to a real system

Human-Centered Design of a Collaborative Robotic System for the Shoe-Polishing Process

Demand for automated processes in the manufacturing industry is now shifting toward flexible, human-centered systems that combine productivity and high product quality, thus combining the advantages of automated and robotic systems with the high-value-added skills of operators and craftsmen. This trend is even more crucial for small and medium-sized enterprises operating in the “Made in Italy” fashion industry. The paper presents the study, simulation, and preliminary testing of a collaborative robotic system for shoe polishing that can reduce manual labor by limiting it to the finishing stage of the process, where the aesthetic result is fully achieved, with a benefit also in terms of ergonomics for the operator. The influence of process parameters and design solutions are discussed by presenting preliminary test results and providing hints for future developments

Design of a miniaturized work-cell for micro-manipulation

The paper describes the design and development of a miniaturised workcell devoted to the robotized micro manipulation and assembly of extremely small components, jointly carried out by the University of Brescia, University of Bergamo, University of Ancona and the Institute of Industrial Technologies and Automation of the Italian National Research Council in the framework of the project PRIN2009 MM&A, funded by MIUR. Besides analyzing theoretical and practical aspects related to the design of the work cell components (positioning and orienting devices, grippers, vision and control systems), an automated test bed for the assembly of micro pieces whose typical dimension belongs to the submillimeter scale range has been implemented. The perspective is to contribute to the realization of general automatic production systems at the moment absent for objects of these dimensions

Design of a miniaturized work-cell for micro-manipulation

The paper describes the design and development of a miniaturised workcell devoted to the robotized micro manipulation and assembly of extremely small components, jointly carried out by the University of Brescia, University of Bergamo, University of Ancona and the Institute of Industrial Technologies and Automation of the Italian National Research Council in the framework of the project PRIN2009 MM&A, funded by MIUR. Besides analyzing theoretical and practical aspects related to the design of the work cell components (positioning and orienting devices, grippers, vision and control systems), an automated test bed for the assembly of micro pieces whose typical dimension belongs to the submillimeter scale range has been implemented. The perspective is to contribute to the realization of general automatic production systems at the moment absent for objects of these dimensions

Microwave Photonic Notch Filter Based on Dynamic Brillouin Gratings Generated by PRBS Signals

A method to create a microwave notch filter through dynamic Brillouin gratings is proposed and numerically demonstrated. It exploits the thumbtack correlation peaks of pseudo random bit sequences

Effect of Graphene Coating on Space Charge Characteristic of XLPE and Semiconductive Layer at Different Temperatures

DC cross-linked polyethylene (XLPE) power cables are being used recently for HV/EHV applications, the reliability of which is claimed to be significantly affected by space charge accumulation in the insulating material. Many methods have been provided for limiting the injection and accumulation of space charge. In the paper, three kinds of specimens with graphene coating applied on a sandwich composed of XLPE and semiconductive layer were made. Space charge distribution of specimens was measured at 10 kV/mm and 40 kV/mm under room temperature and 60 °C. The measurement results show that positive charges are injected and accumulate in reference XLPE specimen. Negative charge accumulates in XLPE, and the quantity of positive charge injected from anode is significantly reduced, when graphene is coated on the semiconductive side. Little space charge is injected into XLPE coated with graphene, and positive charge accumulates near the interface between XLPE and electrode, which lowers electric field near the anode. Graphene layer introduced deeper trap distribution, thus making difficult negative charge injection from the cathode into XLPE

Tumor-Infiltrating Lymphocyte Recognition in Primary Melanoma by Deep Learning Convolutional Neural Network

The presence of tumor-infiltrating lymphocytes (TILs) is associated with a favorable prognosis of pri-mary melanoma (PM). Recently, artificial intelligence (AI)-based approach in digital pathology was proposed for the standardized assessment of TILs on hematoxylin and eosin-stained whole slide images (WSIs). Herein, the study applied a new convolution neural network (CNN) analysis of PM WSIs to automatically assess the infiltration of TILs and extract a TIL score. A CNN was trained and validated in a retrospective cohort of 307 PMs including a training set (237 WSIs, 57,758 patches) and an inde-pendent testing set (70 WSIs, 29,533 patches). An AI-based TIL density index (AI-TIL) was identified after the classification of tumor patches by the presence or absence of TILs. The proposed CNN showed high performance in recognizing TILs in PM WSIs, showing 100% specificity and sensitivity on the testing set. The AI-based TIL index correlated with conventional TIL evaluation and clinical outcome. The AI-TIL index was an independent prognostic marker associated directly with a favorable prognosis. A fully automated and standardized AI-TIL appeared to be superior to conventional methods at differentiating the PM clinical outcome. Further studies are required to develop an easy-to-use tool to assist pathologists to assess TILs in the clinical evaluation of solid tumors. (Am J Pathol 2023, 193: 2099-2110; https://doi.org/10.1016/j.ajpath.2023.08.013

Effectiveness of Ginseng, Rutin and Moringa for the Treatment of Erectile Dysfunction: A Systematic Review

Introduction, The aim of this systematic review was to evaluate the current evidence for the effectiveness of ginseng, Rutin and Moringa for treating erectile dysfunction. Methods, A broad search of the Scopus, PubMed, Cochrane and Web of Science databases was performed in complicance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The following criteria were required for articles to be included in the review: English language; observational studies (cohort studies, case control/comparative studies, single-arm studies); randomized controlled trials; non-randomized comparative studies; case series; number of participants: ≥5 for case series or ≥5 patients per group for comparative studies. The Cochrane risk of bias (RoB) assessment tool for RCTs was used to assess the risk of bias of included studies. Results, Seven full-text articles were included in this review. All studies were randomized controlled trials. No studies on Rutin and Moringa alone matched the inclusion criteria. The methodological quality of the RCTs was variable. In all studies, the group treated with ginseng reported an improvement of erectile function (EF) compared to the control groups. IIEF and IIEF-5 were used to evaluate erectile function in six studies and in four of them, the improvement of the scores in the group treated with ginseng over the control group reached the statistical significance. Conclusion, This review suggests a positive effect of ginseng on EF in men. The association of ginseng along with other nutritional components with potential beneficial effects on ED appears promising and deserves further investigation in large randomized controlled trials