Distance-Based Formation Control for Fixed-Wing UAVs with Input Constraints: A Low Gain Method
Francisco F.C. Rego
Round 1
Reviewer 1 Report
1) Why did you formalize the problem as a control problem in nonholonomic systems?
2) Why did you formalize your problem as that in a 2D? Because, the UAV with a fixed-wing should be treated in a 3D space, if a practical implementation would be considered generally.
3) For controlling any nonholonomic system with an input constraint, the reviewer considers in general any robust back stepping approach or any sliding mode approach as a powerful approach. Of course, we can find many literature concerning with several extensions to a formation problem for such a system. For example, see the followings:
a) Zhong Zheng and Hui Yi, Backstepping control design for UAV formation with input saturation constraint and model uncertainty, Proc. of 2017 36th Chinese Control Conference (CCC)
b) Junbao Wei, Haiyan Li, Ming Guo, Jing Li, and Huang Huang, Backstepping Control Based on Constrained Command Filter for Hypersonic Flight Vehicles with AOA and Actuator Constraints, Int. J. of Aerospace Engineering, Volume 2021, Article ID 8620873.
c) Meijiao Zhao, Yan Peng, Yueying Wang, Dan Zhang, Jun Luo, Huayan Pu, Concise leader-follower formation control of underactuated unmanned surface vehicle with output error constraints, Transactions of the Institute of Measurement and Control, Vol. 44, No. 5, pp. 1081-1094, 2022
4) Why did you adopt the concept of distance-based potential function is this research? Of course, we know that the designed potential function can be used to design the low-gain-based controller so that any velocity constraints can be satisfied.
Author Response
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Author Response.pdf
Reviewer 2 Report
The paper proposes a gradient-based formation control algorithm for unicycle vehicles with limited speed and yaw rate. Although the theoretical contributions are not major, the paper is well written, clear and contains interesting results and realistic simulations. My only two minor comments are the following:
-In equation 1 the angular rate is denoted with the greek letter omega, but in the rest of the paper it is denoted with the letter "w".
-It seems that at the end of line 153 it should be written "for all $j\in\mathcal{N}_i$".
-The authors should define the variables w^r_{i,1max} and w^l_{i,1max} before or right after equation 14.
Author Response
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Author Response File: Author Response.pdf
