Research on PID Position Control of a Hydraulic Servo System Based on Kalman Genetic Optimization
Round 1
Reviewer 1 Report
A set of PID controller based on Kalman genetic optimization is designed, and is applied to established hydraulic servo system. The position tracking and anti-interference ability of the system is studied. Genetic algorithms is used to turn PID parameters.Kalman filter is proposed for the GA optimized PID controller to reduce the effect of external interference on the system and to enhance the anti-interference ability.
(1) In 3.1, no explanation on coding is available. In Line 298, only all individuals for P constitute the initial population. It is unreasonable.
(2) In Eq.(21), J stands for the optimal index. It’s definition is required to be added.
(3) In Fig.8, output for the controller GA-PID should be given to confirm its perofrmance.
(4) In Page 16, GA-PID’s anti-interference ability should be examined to verify its advantage over conventional PID.
Author Response
Thanks for your comments concerning our manuscript entitled “Research on PID position control of hydraulic servo system based on Kalman genetic optimization” (ID: actuators-1745860). Those comments are valuable for revising and improving our paper with important guiding significance. We have made correction according to the comments, revised portion are marked in the paper using the "track changes" feature. Our response to your comments is in the coverletter.Thank you in advance for your time.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Dear authors,
Your article presents an attempt to design an adaptive PID controller of a servo-valve hydraulic system using genetic algorithm optimisation and a Kalman filter. In my opinion, the subject matter is appropriate for the journal. The mathematical model is constructed correctly, and the control objectives are correct. However, I have some suggestions:
1. Your reference list is extensive and includes 37 positions. However, there is not a single reference from MDPI Actuators. In my opinion, you should better justify your subject as suitable for the journal you want to publish in.
2. Fig. 1 contains markings of hydraulic components that do not comply with the standards. Correct symbols for motor, pump, servo valve and actuator should be shown.
3. lines 186-190 - the load force. You list the components of the load force without considering the external load of the actuator. There is an FL symbol in eq.4-8. Also, there is no FL value in Table 1. What was the value of the external load of the cylinder in simulations?
4. Section 3.2, point 2 (lines 299-307) - I think more detailed comments on the construction of the fitness function and values of the c1-c4 parameters are required since the form of this function is crucial for the correctness of the optimisation process.
5. Your genetic optimisation process led to GA-PID with an almost doubled Kd value compared to the regular PID. As a result, it gives a large-amplitude fluctuation of the output signal (which is the spool position) (fig.8c, 11a, 11b). Do you think that could be acceptable in a real system?
6. Section 3.2, point 4 (lines 315-322). What were the exact values of the crossover and mutation probability in the simulations?
7. Fig.11. There is no visible change in the output signal after the disturbance using K_GA_PID. Perhaps changing the colour of the graph to a darker colour or enlarging the area after a distortion would improve readability. In my opinion, it's not possible to compensate for such a disturbance without any change in the output signal value.
8. Adding gridlines in charts (Fig.8,10,11) would increase the readability.
9. Do you plan any laboratory experiments with your controller ?
Regards
Author Response
Thanks for your comments concerning our manuscript entitled “Research on PID position control of hydraulic servo system based on Kalman genetic optimization” (ID: actuators-1745860). Those comments are valuable for revising and improving our paper with important guiding significance. We have made correction according to the comments, revised portion are marked in the paper using the "track changes" feature. Our response to your comments is in the coverletter.Thank you in advance for your time.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
1 The controller outputs to confirm how well it works are still not given. And how dose it behavour under uncertain external load interference.
2 In figure 12(a), a response process on the controlled signal rising by K_GA_pid is not shown. It should be included.
3 English should be deeply improved.
Author Response
Thanks for your comments concerning our manuscript entitled “Research on PID position control of hydraulic servo system based on Kalman genetic optimization” (ID: actuators-1745860). Those comments are valuable for revising and improving our paper with important guiding significance. We have made correction according to the comments, revised portion are marked in the paper using the "track changes" feature.Details of the response can be found in the attached document. Thank you in advance for your time.
Author Response File: Author Response.pdf
Reviewer 2 Report
Dear Authors,
The recommended amendments have been made.
In my opinion, the article can be published.
Regards,
Author Response
Thank you again for you positive comments and valuable suggestions to inprove the quality of our manuscript.
