47 research outputs found
Process monitoring and industrial informatics for on-line optimization of Welding Procedure Specifications (WPS) in Gas Tungsten Arc Welding (GTAW) – Industry 4.0 for robotic additive re-manufacturing of aeroengine components
Industry 4.0, the scheme that drives the fourth industrial revolution, has been, since its conception, reshaping the manufacturing industry. To advance current industrial chains into the smart factories of the future, cyber-physical systems are monitored and communicate with each other to ensure transparent interoperability, giving birth to the emerging field of industrial informatics. To enable the repair and recycling of high value jet engine compressor blades, additive manufacturing is utilized. The complex geometries and asymmetrical wear of the blades require robotic welding systems to be trained by experienced human welding engineers in order to be able to adapt to differing components. Demonstrated in this paper, process monitoring and industrial informatics are introduced to the adaption of Welding Procedure Specifications (WPS) utilized by a developing robotic system for the additive re-manufacturing of aeroengine components. Using a novel variant of Gas Tungsten Arc Welding (GTAW), the robotic welding system under development is a product of an industry-academia collaboration between the Enabling Sciences for Intelligent Manufacturing Group (ESIM) of the University of Sheffield and VBC Instrument Engineering Ltd
Improving productivity and worker conditions in assembly : part 2 : rapid deployment of learnable robot skills
Collaborative robots (cobots) have a strong potential to improve both productivity as well as the working conditions of assembly operators by assisting in their tasks and by decreasing their physical and cognitive stress. The use of cobots in factories however introduces multiple challenges: how should the overall assembly architecture look like? How to
allocate specific (sub)tasks to the operator or the cobot? How to program and deploy the cobot? How to make changes to the robot program?
In this paper dilogy, we briefly highlight our recent contributions to this field. In part I we presented our collaborative
architecture for human-robot assembly tasks and discussed the working principles of our task allocation framework, based upon agent capabilities and ergonomic measurements. In this second part we focus on our programming by demonstration approach targeted at expediting the deployment of learnable robot skills
Enhanced Positioning Algorithm Using a Single Image in an LCD-Camera System by Mesh Elements' Recalculation and Angle Error Orientation
In this article, we present a method to position the tool in a micromachine system based on a camera-LCD screen positioning system that also provides information about angular deviations of the tool axis during its running. Both position and angular deviations are obtained by reducing a matrix of LEDs in the image to a single rectangle in the conical perspective that is treated by a photogrammetry method. This method computes the coordinates and orientation of the camera with respect to the fixed screen coordinate system. The used image consists of 5 × 5 lit LEDs, which are analyzed by the algorithm to determine a rectangle with known dimensions. The coordinates of the vertices of the rectangle in space are obtained by an inverse perspective computation from the image. The method presents a good approximation of the central point of the rectangle and provides the inclination of the workpiece with respect to the LCD screen reference system of coordinates. A test of the method is designed with the assistance of a Coordinate Measurement Machine (CMM) to check the accuracy of the positioning method. The performed test delivers a good accuracy in the position measurement of the designed method. A high dispersion in the angular deviation is detected, although the orientation of the inclination is appropriate in almost every case. This is due to the small values of the angles that makes the trigonometric function approximations very erratic. This method is a good starting point for the compensation of angular deviation in vision based micromachine tools, which is the principal source of errors in these operations and represents the main volume in the cost of machine elements’ parts.The authors want to thank the University Center of Defense at the Spanish Air Force Academy,
MDE-UPCT, for financial suppor
Underactuated Rehabilitation Robotics for Hand Function
Normal hand function plays an important role in daily life. At present, the incidence of hand dysfunction caused by diseases such as cerebral palsy or stroke is increasing year by year. For the rehabilitation of hand dysfunction, in addition to surgical treatment, effective rehabilitation exercise is also particularly important. It is also a necessary link in the efficient and intelligent development of rehabilitation medicine to develop robots that can effectively help patients with rehabilitation hand functions.In this paper, based on the analysis of the design principles and objectives of the rehabilitation robot with hand function, the kinematics model of the rehabilitation robot with hand function is constructed,based on top-down principle in the design of the machine, the design of the machine hand function rehabilitation robots design optimization process framework, and based on the kinematics model and the virtual prototype technology, build its skeleton model, and carries on the kinematics simulation analysis, the design is verified the correctness of the hand function rehabilitation robot kinematics model
Decentralized Multi-Floor Exploration by a Swarm of Miniature Robots Teaming with Wall-Climbing Units
In this paper, we consider the problem of collectively exploring unknown and
dynamic environments with a decentralized heterogeneous multi-robot system
consisting of multiple units of two variants of a miniature robot. The first
variant-a wheeled ground unit-is at the core of a swarm of floor-mapping robots
exhibiting scalability, robustness and flexibility. These properties are
systematically tested and quantitatively evaluated in unstructured and dynamic
environments, in the absence of any supporting infrastructure. The results of
repeated sets of experiments show a consistent performance for all three
features, as well as the possibility to inject units into the system while it
is operating. Several units of the second variant-a wheg-based wall-climbing
unit-are used to support the swarm of mapping robots when simultaneously
exploring multiple floors by expanding the distributed communication channel
necessary for the coordinated behavior among platforms. Although the
occupancy-grid maps obtained can be large, they are fully distributed. Not a
single robotic unit possesses the overall map, which is not required by our
cooperative path-planning strategy.Comment: Accepted for publication in IEEE-MRS 2019, Rutgers University, New
Brunswick (NJ), US
Exoskeleton-Mediated Physical Human-Human Interaction for a Sit-to-Stand Rehabilitation Task
Sit-to-Stand (StS) is a fundamental daily activity that can be challenging
for stroke survivors due to strength, motor control, and proprioception
deficits in their lower limbs. Existing therapies involve repetitive StS
exercises, but these can be physically demanding for therapists while assistive
devices may limit patient participation and hinder motor learning. To address
these challenges, this work proposes the use of two lower-limb exoskeletons to
mediate physical interaction between therapists and patients during a StS
rehabilitative task. This approach offers several advantages, including
improved therapist-patient interaction, safety enforcement, and performance
quantification. The whole body control of the two exoskeletons transmits online
feedback between the two users, but at the same time assists in movement and
ensures balance, and thus helping subjects with greater difficulty. In this
study we present the architecture of the framework, presenting and discussing
some technical choices made in the design.Comment: 7 pages, 6 figures, submitted to 2024 IEEE The International
Conference on Robotics and Automation (ICRA
Lower limb exoskeleton robot and its cooperative control: A review, trends, and challenges for future research
Effective control of an exoskeleton robot (ER) using a human-robot interface is crucial for assessing the robot's movements and the force they produce to generate efficient control signals. Interestingly, certain surveys were done to show off cutting-edge exoskeleton robots. The review papers that were previously published have not thoroughly examined the control strategy, which is a crucial component of automating exoskeleton systems. As a result, this review focuses on examining the most recent developments and problems associated with exoskeleton control systems, particularly during the last few years (2017–2022). In addition, the trends and challenges of cooperative control, particularly multi-information fusion, are discussed
Overview of the Financial Reporting and Auditing Regime in South Eastern European Countries
ABSTRACT: Since companies nowdays are going more and more cross border and becoming multinational, the adoption and implementation of International Financial Reporting (IFRS) and Auditing Standards (ISA) are as a result of globalization that has become a very important part of our world. In this regard lately, the accounting and auditing profession has undergone through major changes and developments. As part of these transformations were no different developing countries, since they are part of globalization as well. In this study, we present an outline of the financial reporting and auditing regime of countries in South Eastern Europe where as well we outline challenges faced by developing countries in adopting and implementing IFRSs and IASs. South Eastern European Countries such as Ex Yugoslavia countries face similar challenges and opportunities as part of their route to integrate and harmonize their financial and economic system with those of European Union, as a result of the same and unique characteristics of old and ex Yugoslavian system.Thus this study can help readers to have an overview of regulatory framework in these countries and to understand the similar and different challenges and opportunities, as well as it can serve as a base for a future research of the accounting and auditing professional developments in these countries. In this study, we present conclusions on why developing countries such as those that are part of this study choose to adopt international standards, and as well conclusions are drawn about the future of these standards for developing countries. Ongoing with the economic transition reforms undertaken within this region, financial reporting and auditing systems have been altered to converge with International Financial Reporting Standards, International Standards on Auditing, and towards a new emphasis on quality assurance for audit and external oversight mechanisms, to support the convergence process.