Synchronization of Electrical Drives via EtherCAT Fieldbus Communication Modules

Synchronization between devices (in particular drive systems) is paramount for multi-axis motion control systems used in Computerized Numerical Control (CNC) machines, robots, and specialized technology machines used in many areas of the manufacturing industry. EtherCAT is an Ethernet-based network that is one of the most popular industrial networks for multi-axis motion control systems. EtherCAT is standardized in the IEC 61158 and IEC 61784 standards. In the article, an EtherCAT communication network for electrical drives is presented. The article focuses on the synchronization in the EtherCAT network consisting of one master device and slave servo drive devices. Special attention is given to synchronization mechanisms in EtherCAT, such as distributed clocks in slave servo drives devices. For this purpose, a laboratory stand was built consisting of two prototype servo drive devices with BLDC motors equipped with EtherCAT communication modules. A description of the working developed EtherCAT communication modules is given. Authors in communication modules ware used an EtherCAT Slave Controller (ESC) chip (AX58100) to implement lower EtherCAT layers. EtherCAT application layer was implemented in software form on a 32-bit microcontroller, based on CANopen over EtherCAT (CoE) CAN in Automation 402 (CiA402) profile. This research’s main contribution was to show the time dependencies regarding synchronization in terms of data flow in the EtherCAT communication stack in slave servo drive devices. The research results showed that the synchronous operation of drives is mainly influenced not by the mechanism of distributed clocks that ensures synchronization in the EtherCAT network but the implementation of the highest layer of the communication stack in slave servo drive devices. Experimental results are presented that prove the modules’ adequacy for use in high-performance motion control systems.

On the Divergence Mechanisms Analysis of a Vibrating Blade subjected to Repetitive Rubs with an Abradable Coating

Aeronautical compressor fans currently operate with minimal blade-casing clearance. This therefore makes the occurrence of rub events very likely. Under specific circumstances, the blade undergoes excessive amplification of contact-induced oscillations, called hereafter divergence, which can be critical for the structural integrity of the engine. This paper proposes an investigation of the mechanisms responsible for the blade divergence. Experiments are conducted on a fully instrumented laboratory set-up, consisting of a single flat blade being moved towards a rotating cylinder to initiate interactions, while monitoring the vibrations and the evolution of wear on the abradable coating. Two synchronization mechanisms have been identified as facilitating the divergence: (i) the inherent set-up synchronization between the vibration modes related to the horizontal and vertical motion of the blade; (ii) the preferential blade-coating interactions in the vicinity of periodically distributed irregularities of the abradable coating which act as a source of excitation of the vibrations.

Self-organization in natural swarms of Photinus carolinus synchronous fireflies

Fireflies flashing in unison is a mesmerizing manifestation of animal collective behavior and an archetype of biological synchrony. To elucidate synchronization mechanisms and inform theoretical models, we recorded the collective display of thousands of Photinus carolinus fireflies in natural swarms, and provide the first spatiotemporal description of the onset of synchronization. At low firefly density, flashes appear uncorrelated. At high density, the swarm produces synchronous flashes within periodic bursts. Using three-dimensional reconstruction, we demonstrate that flash bursts nucleate and propagate across the swarm in a relay-like process. Our results suggest that fireflies interact locally through a dynamic network of visual connections defined by visual occlusion from terrain and vegetation. This model illuminates the importance of the environment in shaping self-organization and collective behavior.

The Embodied-Enactive-Interactive Brain: Bridging Neuroscience and Creative Arts Therapies

The recognition and incorporation of evidence-based neuroscientific concepts into creative arts therapeutic knowledge and practice seem valuable and advantageous for the purpose of integration and professional development. Moreover, exhilarating insights from the field of neuroscience coincide with the nature, conceptualization, goals, and methods of Creative Arts Therapies (CATs), enabling comprehensive understandings of the clinical landscape, from a translational perspective. This paper contextualizes and discusses dynamic brain functions that have been suggested to lie at the heart of intra- and inter-personal processes. Touching upon fundamental aspects of the self and self-other interaction, the state-of-the-art neuroscientific-informed views will shed light on mechanisms of the embodied, predictive and relational brain. The conceptual analysis introduces and interweaves the following contemporary perspectives of brain function: firstly, the grounding of mental activity in the lived, bodily experience will be delineated; secondly, the enactive account of internal models, or generative predictive representations, shaped by experience, will be defined and extensively deliberated; and thirdly, the interpersonal simulation and synchronization mechanisms that support empathy and mentalization will be thoroughly considered. Throughout the paper, the cross-talks between the brain and the body, within the brain through functionally connected neural networks and in the context of agent-environment dynamics, will be addressed. These communicative patterns will be elaborated on to unfold psychophysiological linkage, as well as psychopathological shifts, concluding with the neuroplastic change associated with the formulation of CATs. The manuscript suggests an integrative view of the brain-body-mind in contexts relevant to the therapeutic potential of the expressive creative arts and the main avenues by which neuroscience may ground, enlighten and enrich the clinical psychotherapeutic practice.

Collision-Free Robot Coordination and Visualization Tools for Robust Cycle Time Optimization

This paper presents novel algorithms and visualization tools for avoiding collisions and minimizing cycle time in multi-robot stations by velocity tuning of robot motions. These tools have the potential to support product/manufacturing engineers in the practical task of adding synchronization instructions to robot programs to overcome the challenges in terms of product design, cycle time, quality control, and maintenance including re-usability of coordination schemes. We propose a range of techniques to achieve that, when additional requirements make the best coordination strategy hard to be chosen. Indeed, our main contributions are (i) considering and minimizing delays introduced by limitation in hardware synchronization mechanisms, (ii) highlighting insights on the relationship between a 3D working space and a path coordination space, and (iii) a computational tool for visualization of shared areas in both work space and path coordination space. Different strategies based on the developed algorithms are evaluated by successfully automatically solving industrial test cases from inspection measurement applications in the automotive industry. A study about how cycle time robustness is significantly influenced by variation in the robot motion execution times is also given.

Self-organization in natural swarms of Photinus carolinus synchronous fireflies

Fireflies flashing in unison is a mesmerizing manifestation of animal collective behavior and an archetype of biological synchrony. To elucidate synchronization mechanisms and inform theoretical models, we recorded the collective display of thousands of Photinus carolinus fireflies in natural swarms, and provide the first spatiotemporal description of the onset of synchronization. At low firefly density, flashes appear uncorrelated. At high density, the swarm produces synchronous flashes within periodic bursts. Using three-dimensional reconstruction, we demonstrate that flash bursts nucleate and propagate across the swarm in a relay-like process. Our results suggest that fireflies interact locally through a dynamic network of visual connections defined by visual occlusion from terrain and vegetation. This model illuminates the importance of the environment in shaping self-organization and collective behavior.

Transformation of Industrial Enterprises in the Digital Economy

The article is devoted to the analysis of transformation processes of high-tech industrial enterprises operating in the digital economy. It is noted that in the modern economy of Russia the technologies of the third and fourth technological paradigm (TP) prevail, therefore the technologies of the fifth and sixth ones are “high” for it. The structure of the transformation processes of a high-tech enterprise in the framework of the development of digital technologies with the allocation of technological levels of automation of the production process is considered. To optimize the processes of technological transformation, the author proposes to use a modified structure. A characteristic feature of the proposed structure is the presence in it of the so-called “intelligent agents”, which are specialized software modules that are controlled by a special data exchange protocol. Modules also have the ability to implement synchronization mechanisms with business objects and provide the technical ability to integrate three or more different information systems.