Variable-order fractional operators were conceived and mathematically formalized only in recent years. The possibility of formulating evolutionary governing equations has led to the successful application of these operators to the modelling of complex real-world problems ranging from mechanics, to transport processes, to control theory, to biology. Variable-order fractional calculus (VO-FC) is a relatively less known branch of calculus that offers remarkable opportunities to simulate interdisciplinary processes. Recognizing this untapped potential, the scientific community has been intensively exploring applications of VO-FC to the modelling of engineering and physical systems. This review is intended to serve as a starting point for the reader interested in approaching this fascinating field. We provide a concise and comprehensive summary of the progress made in the development of VO-FC analytical and computational methods with application to the simulation of complex physical systems. More specifically, following a short introduction of the fundamental mathematical concepts, we present the topic of VO-FC from the point of view of practical applications in the context of scientific modelling.

https://royalsocietypublishing.org/doi/pdf/10.1098/rspa.2019.0498

Applications of variable-order fractional operators: a review

Optimal variable-order fractional PID controllers for dynamical systems

Aside from vast deployment cost reduction, Industrial Wireless Sensor and Actuator Networks (IWSAN) introduce a new level of industrial connectivity. Wireless connection of sensors and actuators in industrial environments not only enables wireless monitoring and actuation, it also enables coordination of production stages, connecting mobile robots and autonomous transport vehicles, as well as localization and tracking of assets. All these opportunities already inspired the development of many wireless technologies in an effort to fully enable Industry 4.0. However, different technologies significantly differ in performance and capabilities, none being capable of supporting all industrial use cases. When designing a network solution, one must be aware of the capabilities and the trade-offs that prospective technologies have. This paper evaluates the technologies potentially suitable for IWSAN solutions covering an entire industrial site with limited infrastructure cost and discusses their trade-offs in an effort to provide information for choosing the most suitable technology for the use case of interest. The comparative discussion presented in this paper aims to enable engineers to choose the most suitable wireless technology for their specific IWSAN deployment.

https://biblio.ugent.be/publication/8655992/file/8655994.pdf

Survey on Wireless Technology Trade-Offs for the Industrial Internet of Things.

Partial fraction expansion–based realizations of fractional-order differentiators and integrators using active filters

Most of the existing controller tuning methods are based on accurate system model and sensitive to some inevitable uncertainties and unmeasurable disturbance. Aiming at this problem, a thorough robustness analysis on a typical kind of fractional-order (FO) delay system has been made in this study. A kind of robust FO proportional and derivative controller is proposed based on phase and gain margins. The tuning methods are demonstrated under different circumstances, namely there is gain variation, time constant variation, order variation or even multiple parameters variations in system transfer function. Simulation results show that the closed-loop control system with the proposed controller can achieve both robustness and satisfactory dynamic performance, and outperform the conventional proportional-integral-derivative controller in all cases.

https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/iet-cta.2017.1145

General robustness analysis and robust fractional-order PD controller design for fractional-order plants

Fractional-order Systems and PID Controllers: Using Scilab and Curve Fitting Based Approximation Techniques

This book presents a guideline for EWMA filter design for industrial wireless networked control system, both theoretically and practically. The filter’s key advantages are simple, effective, low computational overhead. This book also provides a guideline for practical implementation of EWMA filter for improving networked control performance of various process plants. It further discusses not only the advantages of the filter, but also the limitations and how to avoid them when implementing the filter from practical point of view.

WirelessHART™: Filter Design for Industrial Wireless Networked Control Systems

Despite the advantages of the industrial wireless standards such as WirelessHART, ISA100.11a and Wireless Networks for Industrial Automation-Process Automation (WIA-PA), their application still faces a lot of challenges especially when it comes to interfacing with the real plant. This is due to lack of adequate infrastructures such as interfacing circuitry to establish communication between the WirelessHART nodes and the actuators and sensors. Therefore, this paper presents the application of locally developed WirelessHART adaptors for flow process control. The adaptors serve as an interface between the WirelessHART network and the sensor and actuator of the plant. Experimental results of the controllers compared showed that wireless control is possible through the use of the adaptors.

/pdf/implementation-of-flow-control-over-wirelesshart-sensor-32sspwj21c.pdf

Rosdiazli Ibrahim

Papers

Fractional-order Systems and PID Controllers: Using Scilab and Curve Fitting Based Approximation Techniques

WirelessHART™: Filter Design for Industrial Wireless Networked Control Systems

Implementation of flow control over WirelessHART sensor network using WirelessHART adaptors