Research on Variable Universe Fuzzy Multi-Parameter Self-Tuning PID Control of Bridge Crane
Round 1
Reviewer 1 Report
Dear authors,
The paper describes your research on an adjustable Fuzzy PID control, using a self-tuning approach for controlling a Bridge crane. Your analysis and mathematical equations are good, but they lack conciseness. Simple relations that can be simplified should be simplified, for example, derivations of constants that are zero value).
Overall the paper is good and provides evidence of the conducted virtual experiments to back your findings.
My observations are as follows:
1. References
- Line 36, references 1-6. Please ungroup so many references. If those references are important for your research then you should provide details and explanations on why they are important, so that the reader understands why they are referenced. References should not be grouped more than 2 when they first appear in the text.
- Line 72, references 15-20 should be split into several, to detail the applications the authors are referring to.
2. English check
- Line 30: "large and trolleys"
- In line 53, please correct "bird swarm optimization (PSO)"
- In line 63, please rephrase "Finally, in...". This is not the end of research for this particular subject, nor yours.
- Line 91, please rephrase the repetition of the word "control": "Fuzzy controllers, control the control object"
- Line 95, word repetition: "control"
- Lines 232-234, please rephrase the sentence. "the larger .., the smaller .., but the change ..". This is one of the most important sentences of the paper. Please improve it, for a better understanding of the readers.
- Figure 2. Please correct the diagram block names. "Funny controller" should probably be named "Fuzzy controller".
- Line 251, you should not refer to a "sentence".
3. On lines 69-70. Please add more information to the statement that the studied systems are complex and with reduced reliability.
4. Line 142, please correct the notations: "the load has a mass of m1"
5. On lines 148, 154, and 183, please update the format of the equation. The letters are quite small and hard to read.
6. In line 164, please use the equation editor or use superscript, to rewrite the relation 9.8 m/s^2. The "s^2" can be easily avoided.
7. In line 316, please correct the relation using superscript to write s^2, or the equation editor.
8. In Line 188, the "e" and "ec" are mentioned before explaining what these parameters are. Please correct.
9. Lines 202-203, please arrange equation (11)
10. Please add information on what are the parameters presented in table 4 (Ts, Mp, etc.).
11. In figure 8, please specify the working condition number.
12. In figure 9, the title seems to be missing the working condition number. Please correct.
13. For a clearer way of proving your results, please provide a simulation graph of the trolley position, zoomed in on the Trolley Position scale, leaving the time scale unchanged. In this way, the readers can observe the changes in the position of the trolley while compensating for the payload swing during crosswinds and white noise. In this new image, the first 10 seconds of the simulation are not important, but what is very important is how the system variates the trolley position to compensate for the payload swing, which can be very clearly seen in figures 15, 17, 19 and, 21. Right now, figures 14, 16, 18 and, 20 present a smooth control result which probably is not the case, since the system will try to compensate for the white noise disturbance.
14. I also suggest that the authors provide, for a certain working case, a diagram of the computed output parameters of "The universe self-adjusting mechanism". In this way, readers can visually understand what the control methods do when disturbances are introduced within the system and how the method can achieve the presented performances.
15. Please add more information in the conclusions section to back your claim of robustness and adaptability to nonlinear control systems.
16. A self-tuning control is a good idea and has been used in the past by many scientists. Please add a stability analysis of your "Variable Universe Fuzzy Multi-Parameter Self-Tuning PID Control" system that updates the fuzzy parameters in real time. What is the effect on the control system, when the Fuzzy-PID output parameters are adjusted?
Thank you.
Author Response
Please see the attachment.
Author Response File: 
Author Response.docx
Reviewer 2 Report
In this paper, a variable universe fuzzy multiparameter self-tuning PID control strategy (VUFMS-PID) is proposed to control the movement of an overhead crane.
The paper needs a number of corrections before being considered for publication.
1- The paper needs a restructuring in the form of presentation. Tables 1, 2 and 3, as well as figures 3, 4 and 5, can be transferred to an appendix section;
2 - Figures 6 and 7, 8 and 9, 10 and 11, 12 and 13, 14-21, must be placed side by side;
3- Authors must include the control signals used;
4- The results presented are numerical only, experimental results are not presented, therefore the experimental term must be removed from the paper;
5- Authors should discuss in more detail the advantages of control in real applications.
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Reviewer 3 Report
This paper proposes a variable universe fuzzy multi-parameter self-tuning PID (VUFMS-PID) control strategy for controlling the trolley's movement of a bridge crane. This control strategy uses scaling factor variation to dynamically adjust the number of fuzzy control rules based on the system error and error rate of change.
The paper is well written and the results seem to confirm the effectiveness of the proposed controller.
For the validation of this control action, two cases have to be addressed in addition,
1) Case when the load is unknown?
2) What are the limits of applicability? The limits for load and speed?
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Dear authors,
Thank you for updating the paper and responding to my questions and comments.
Your research is in a niche field of the mechanical engineering and can have a big impact on industry cranes that can improve the production process of many factories.
Best of luck with your research!
Reviewer 2 Report
The authors made the requested corrections and clarifications, submitting a new version that can be accepted for publication.
