Flocking of Multi-Agent System with Nonlinear Dynamics via Distributed Event-Triggered Control

Round 1

Reviewer 1 Report

The paper discusses a distributed event-triggered control law with bounded action function for free flocking.

 The paper contains some original contribution and may be published in Applied Sciences journal provided that it will be improved.

 I have the following comments.

The authors claim that „the work concerning the application of ETC to study flocking problem is rare” but they do not refer to them. It is true that they are rare but in my opinion these works should be references and shortly discussed as highly relevant for the paper content.

At least the works on ETC concerning the flocking problem are:

 

„Leader–follower flocking based on distributed event‐triggered hybrid control” by Pian Yu, Li Ding, Zhi‐Wei Liu, Zhi‐Hong Guan, International Journal of Robust and Nonlinear Control, 2016

 

„Flocking with a virtual leader based on distributed event-triggered hybrid control” by Pian Yu, Li Ding, Zhi-Wei Liu, Zhi-Hong Guan, Mei-Xuan Hu, Proceedings of the 32nd Chinese Control Conference, 2013

 

Furthermore, this is not trues that event-based control „has been originally used for the control of discrete-event systems, Petri Nets and finite state machines”. The event-based control has originated in the 50s before the methodology for discrete-event systems has been developed. Please, see and refer to the book which comprehesively addresses the research on event-based systems and early works on event-based control:

 „Event-Based Control and Signal Processing” edited by M. Miskowicz, CRC Press 2016

I suggest to refer to the early paper by

Karl Johan Astrom, Bo Bernhardsson, „Comparison of periodic and event based sampling for first-order stochastic systems”, IFAC Proceedings Volumes, vol. 32, pp. 5006-5011, 1999

that initiated a modern research interest on event-based control and also to the paper
M. Miskowicz, „Send-On-Delta Concept: An Event-Based Data Reporting Strategy”, Sensors, vol. 6(1), pp. 49-63, 2006
as an early reference on event-based communication.

Furthermore, many studies on event-based control and communication have been published in Applied Sciences and Sensors journals in the past. I recommend to refer to them to highlight that MDPI journals are a forum for a debate on event-based systems.

For example, recent contributions are:

Signal Source Localization of Multiple Robots Using an Event-Triggered Communication Scheme by Ligang Pan, Qiang Lu, Ke Yin and Botao Zhang

Appl. Sci. 2018, 8(6), 977

 

A Robust Asynchronous Sampled-Data Control Design for Nonlinear Systems with Actuator Failures by Leonardo Acho and Pablo Buenestado

Appl. Sci. 2017, 7(9), 875

 

A Cognitive-Inspired Event-Based Control for Power-Aware Human Mobility Analysis in IoT Devices

by Rafael Pérez-Torres, César Torres-Huitzil and Hiram Galeana-Zapién

Sensors 2019, 19(4), 832

 

Less Data Same Information for Event-Based Sensors: A Bioinspired Filtering and Data Reduction Algorithm

by Juan Barrios-Avilés, Alfredo Rosado-Muñoz, Leandro D. Medus, Manuel Bataller-Mompeán and Juan F. Guerrero-Martínez

Sensors 2018, 18(12), 4122

Artificial-Intelligence-Based Prediction of Clinical Events among Hemodialysis Patients Using Non-Contact Sensor Data

by Saurabh Singh Thakur, Shabbir Syed Abdul, Hsiao-Yean (Shannon) Chiu, Ram Babu Roy, Po-Yu Huang, Shwetambara Malwade, Aldilas Achmad Nursetyo and Yu-Chuan (Jack) Li

Sensors 2018, 18(9), 2833

Event-Based Communication and Finite-Time Consensus Control of Mobile Sensor Networks for Environmental Monitoring

by Yu Hu, Qiang Lu and Yanzhu Hu

Sensors 2018, 18(8), 2547

 

New Control Paradigms for Resources Saving: An Approach for Mobile Robots Navigation

by Rafael Socas, Raquel Dormido and Sebastián Dormido

Sensors 2018, 18(1), 281

 

Event-Based Sensing and Control for Remote Robot Guidance: An Experimental Case

by Carlos Santos, Miguel Martínez-Rey, Felipe Espinosa, Alfredo Gardel and Enrique Santiso

Sensors 2017, 17(9), 2034

Author Response

 Many thanks for your positive comments and your precious time expended in an attempt to improve our paper. Your insightful advice is very much appreciated. We attempted to address all your concerns, which doubtlessly improve the paper and our hope is that these efforts will meet your approval. Our detailed reflections can be found in the attachment below.

Author Response File: Author Response.pdf

Reviewer 2 Report

The main contribution of this paper is to propose the ETC framework for flocking problem as the authors describe in Section 1. However, the reviewer can easily get similar papers [1-4]. Through the paper, the authors have not claimed the other studies and compared with them. Therefore, the reviewer cannot evaluate its originality.  Additionally, the authors have not described the connection between the theoretical analysis and the simulation result. According to the context of the discussion about the motivation of the proposal, the simulation result should indicate some advantage of the convergence speed, the applicability, the stability, and so on. From the points, the reviewer decides the paper should not be published at this time.

[1] Xun W., Yi W., Liu X., Yi X., Wang Y., Event-Triggered Communication Mechanism for Distributed Flocking Control of Nonholonomic Multi-agent System. International Conference on Sensing and Imaging ICSI 2018: Advances in Swarm Intelligence, 53-65, 2018.

[2] Yu P., Ding L., Liu Z.W., Guan Z.H., Leader-follower flocking based on distributed event-triggered hybrid control. International Journal of Robust and Nonlinear Control, 26(1), 2015.

[3] Sun F., Wang R., Zhu W., Li Y., Flocking in nonlinear multi-agent systems with time-varying delay via event-triggered control, Applied Mathematics and Computation, 350(1): 66-77, 2019.

[4] Losada M.G., Contributions to Networked and Event-Triggered of Linear Systems,  Springer, 2016.

[5] Fang, C., Zhang Y., Huang S., Distributed event-triggered flocking control of nonlinear multi-agent systems, 2017 Chinese Automation Congress (CAC), 2965-2970, 2017.

Author Response

Many thanks for your positive comments and your precious time expended in an attempt to improve our paper. Your insightful advice is very much appreciated. We attempted to address all your concerns, which doubtlessly improve the paper and our hope is that these efforts will meet your approval. Our detailed reflections can be found in the attachment below.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

All of my concerns have been considered to be improved.