Modeling and verification of helicopter roll-on takeoff based on optimal control theory
Aircraft Engineering and Aerospace Technology
ISSN: 0002-2667
Article publication date: 11 April 2023
Issue publication date: 2 May 2023
Abstract
Purpose
The paper aims to establish a comprehensive optimization analysis model for a helicopter roll on the ground and take off based on optimal control method. The trajectory and control of the entire process are studied, and the key factors affecting the helicopter takeoff distance are analyzed.
Design/methodology/approach
First, based on the equivalent stiffness and damping, the landing gear model is established, and a six-degree-of-freedom helicopter model is formed. Then, the simulation of the roll-on takeoff is transformed into a nonlinear optimal control problem (NOCP). Meanwhile, a hybrid single-multiple shooting method-based transcription process is used for discretizing the problem, leading to a finite nonlinear programming model, which is solved by sequential quadratic programming. Finally, the process was calculated and compared with flight test data, which verified the feasibility of the NOCP. The influence of takeoff weight, takeoff power and liftoff airspeed on the takeoff distance of the helicopter was analyzed.
Findings
The results show that the takeoff weight can be increased by 17% under the maximum takeoff power, which is roll-on takeoff at an altitude of 0 m. When the helicopter takes off with the maximum weight at an altitude of 5000 m, the liftoff airspeed should be over 49.2 km/h.
Originality/value
The novelty of this paper lies in the comprehensive consideration of helicopter taxiing and taking-off phases, and the application of optimal control theory to establish a comprehensive analysis model, which can quickly analyze the maximum takeoff weight, takeoff distance, optimal liftoff speed and so on. Meanwhile, the method is verified based on the flight data.
Keywords
Acknowledgements
Declaration of interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare the following financial interests/personal relationships which may be considered as potential competing interests.
Data availability statement: Some or all data, models or code generated or used during the study are proprietary or confidential in nature and may only be provided with restrictions. Items and restrictions: 1. The Code and primary parameters of the helicopter during the study are confidential in nature, cannot provide; 2. the flight test data for validation may only be provided dimensionless in this paper.
Citation
Deng, J., Chen, J. and Wang, Z. (2023), "Modeling and verification of helicopter roll-on takeoff based on optimal control theory", Aircraft Engineering and Aerospace Technology, Vol. 95 No. 6, pp. 849-857. https://doi.org/10.1108/AEAT-04-2022-0097
Publisher
:Emerald Publishing Limited
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