Adaptive Fuzzy Control for Flexible Robotic Manipulator with a Fixed Sampled Period

Round 1

Reviewer 1 Report

The authors have proposed an adaptive fuzzy back stepping sampled data control method for the flexible robotic manipulator. Specifically, the flexible robotic manipulator is transformed into a fifth-order non-strict feedback nonlinear system and a backstepping adaptive fuzzy controller is developed for the system to estimate the unknown internal dynamics. The FLS is used to solve the “explosion of complexity” problem. The system with the controller has been mathematically proved to be semi-globally uniformly ultimately bounded, to be validated in simulation.

Moreover, the authors need to clarify the motivation and the research gap clearly in the introduction. The developed control method is meant to provide optimal performance while taking account of limited network bandwidth and fixed sampled data. The manuscript focused on the derivation/proof of the controller design, with little context and evaluation conducted.

Therefore, the work presented is consider incomplete and a substantial change are required before the manuscript can be considered for publication. The overall writing and format also need major improvements. Specific comments are as listed below,

 

Specific comments:

1.       There are many grammatical mistakes in the article: e.g. “which utilizes is widely used…”’ in line 20, “In [18], by transforming the single-link flexible 28 robotic manipulator system into a fifth-order” in line 28-29, “How can we prove…is an essential problem” in line 45-46, and so on. The authors need to do more critical proofreading on the manuscript.

 

2.       Line 11, need to write the full form of the acronym ‘FLS’ in the article for the first use.

 

3.       Line 25-26, need to explain why knowing the internal dynamics of flexible manipulator is a problem, hence a controller design based on unknown dynamics of flexible manipulator is beneficial.

 

4.       Line 28: Avoid block citation as ‘[10-20]’.

 

5.       Line 29-30, the statement “to address the unknown internal dynamics” is confusing. Does it mean the backstepping adaptive fuzzy controller is developed for the fifth-order transformation model to predict or estimate the unknow internal dynamics?

 

6.       Line 31-36, need to explain what the “explosion of complexity” problem is and the result of the problem. The reference [19] has already addressed the ‘explosion of complex’ problem with a different approach. What is the significance of the proposed approach over the existing work? The contribution of this work is unclear.

 

7.       Section 2&3 : This section could be better organised. It is hard to follow.

 

8.       Line 286-287, better to list the parameters in a table with explanation.

 

9.       X axis label is missing in figure 1. Y axis labels are missing in all figures.

 

10.   The controller stability has been proved but the controller performance has not been presented in simulation.

 

11.   It is unclear how the simulation parameters were chosen as well as the purpose of conducting the simulation. Are these parameters from a previous work, or selected with a reason? What is the context of the simulation?

 

12.   Figure 2-5, the results are neither explained nor discussed against previous work. The proposed controller stabilizes the simulated system model, but it is unclear how the proposed controller performs compared with other controllers (for example, a continuous controller in a similar case.)

Author Response

We are grateful for your valuable comments and suggestions on the manuscript (electronics-1807572). According to these comments and suggestions, we have carefully revised the manuscript and prepared our point-by-point response as follows. Hopefully, the revised manuscript is satisfactory.

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

1. This paper presents an adaptive fuzzy control for a flexible robotic manipulator with a fixed sample rate. The authors introduced the fuzzy control scheme, offered a thorough stability analysis, and gave the simulation results. 

2. It will be nice to see experimental results on the single link manipulator, as shown in (1).

3. More simulation results with different sampling rates will help improve the quality of the paper.

Author Response

We are grateful for your valuable comments and suggestions on the manuscript (electronics-1807572). According to these comments and suggestions, we have carefully revised the manuscript and prepared our point-by-point response as follows. Hopefully, the revised manuscript is satisfactory.

Please see the attachment.

 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors have addressed the previous comments and the manuscript is acceptable for publication.