Research Article | | Peer-Reviewed

Mathematical Modelling and Simulation of a Two-Stage Nozzle Flapper Electro-Hydraulic Servo Valve for Aircraft Landing Gear Operation

Received: 1 October 2025     Accepted: 13 October 2025     Published: 7 November 2025
Views:       Downloads:
Abstract

Electro-hydraulic servo valves (EHSVs) are extensively used in aerospace actuation systems due to their capability to provide precise and rapid control of hydraulic flow. However, accurate mathematical modeling is essential to capture their complex nonlinear dynamics for purposes of simulation, analysis, and control system design. This paper presents a comprehensive mathematical model of a two-stage nozzle flapper EHSV applied to aircraft landing gear operations. The servo valve is divided into five key subsystems: the servo amplifier, voltage-current converter, torque motor, nozzle flapper mechanism, and spool valve integrated with a feedback sensor. Transfer functions are derived for each subsystem and subsequently combined to form an overall system model. The model’s accuracy is validated through simulations conducted in MATLAB/Simulink, enabling detailed performance analysis under various input conditions. Simulation results are used to evaluate system stability, transient response, and overall accuracy. The findings reveal a rapid settling time of 0.85 s, negligible overshoot, and a fine spool displacement of 1.43 × 10-4 m (0.143 mm), demonstrating the model’s capability to achieve stable and precise hydraulic control. These findings highlight the significant potential of the proposed mathematical model to enhance the dynamic performance of aircraft landing gear systems by providing more accurate, stable, and responsive control of hydraulic actuation.

Published in American Journal of Aerospace Engineering (Volume 11, Issue 2)
DOI 10.11648/j.ajae.20251102.13
Page(s) 36-45
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2025. Published by Science Publishing Group

Keywords

Electro-hydraulic Servo Valve, Landing Gear System, Nozzle Flapper, Spool Displacement

References
[1] Afatsun, A. C. (2019). Modeling of two stage nozzle-flapper type electrohydraulic servovalves.
[2] Afwan, M., Memon, D. S., Pawar, Y. G., & Kainge, S. P. (2017). A Study on Landing Gear Arrangement of an, 15730-15738.
[3] Anderson, J., & Bowden, M. (2022). Introduction to flight.
[4] Changhai, L., & Hongzhou, J. (2014). A seventh-order model for dynamic response of an electro-hydraulic servo valve. Chinese Journal of Aeronautics, 27(6), 1605-1611.
[5] Chen, Z., & Wang, W. (2018). Analysis of Temperature Characteristics of Electro-hydraulic Servo Valve Based on AMESim, 154(Meees), 47-53.
[6] Code, L. (2019). Thesis for the Degree of Doctor of Philosophy A Study on Control of an Electro- Hydraulic Servo Valve.
[7] Dinca, L., Corcau, J. I., & Vaden, C. V. (2023). Drive Systems for Landing Gears Numerically Simulated in AMESim Software.
[8] Duan, S. (2022). applied sciences Health Assessment of Landing Gear Retraction / Extension Hydraulic System Based on Improved Risk Coefficient and FCE Model.
[9] Efe, Y. (2014). Dynamic Model of a Hydraulic Servo System for a Manipulator Robot, 70.
[10] Fadel, M. Z. (2023). Hybrid Control Algorithm Sliding Mode-PID for an Electrohydraulic Servo Actuator System Based on Particle Swarm Optimization Technique, 56(1), 153-163.
[11] Gao, B., Zhang, W., Zheng, L., & Zhao, H. (2023). Research on high-precision position control of valve-controlled cylinders based on variable structure control. Machines, 11(6), 623.
[12] Gebrehiwet, L. (2020). electro-hudraulic servo control system design of reverse thrust.
[13] Gordi, D., Babi, M., & Jovi, N. (2004). Modelling of Spool Position Feedback Servovalves.
[14] Haider, S. (2020). Applying model based safety assessment for aircraft landing gear system certification. Proceedings - Annual Reliability and Maintainability Symposium.
[15] Huang, C., & Jia, Y. (2019). Optimal Design of Aircraft Landing Gear Mechanism Actuating Force. Antlantis Highligths in Engineering, 3(Jimec 2018), 287-292.
[16] Jelali, M., & Kroll, A. (2004). Hydraulic Servo-systems: Modelling, Identification and Control. Surrey, Springer-Verlag(London),. Retrieved from
[17] Kovari, A. (2015). Mathematical model and simulation of electrohydraulic servo systems. Conference Paper.
[18] Lee, C. H., & Kim, S. J. (2021). Performance Analysis of Servo Amplifiers in Aerospace Applications. Aerospace Science and Technology, 114, 106793.
[19] Nilsson, J. (2016). Position Control of an Electro-Hydraulic Servo- Valve.
[20] Parambath, J. (2016). Electro-hydraulic Servo Valve Systems. Fluidsy Training Centre Pvt Ltd, 1-7.
[21] Parr, A. (2011). hydraulic and pneumatics. Hydraulics and Pneumatics (First Edit). Elsevier Ltd.
[22] Rawat, S. (2016). Landing gear system. Study Aircraft.
[23] Shri Jain, A. S., Ahmednagar Shri Muthukrishnan, A. S., Ambernath Susan Titus, V., Bengaluru Shri Subbukutti, N. S., Smt Bhuvaneswari, A. M., Smt Faheema AGJ, C.Sonika Sharma, D. (2020). Retractable landing gear system, 2(5).
[24] Scarcelli, F. (2023). RAMS- and mass-based optimization of aircraft on-board system architectures during preliminary aircraft design [Master’s thesis, Politecnico di Torino, Turin, Italy]. Politecnico di Torino Webthesis Repository.
[25] Wong, J. Y. B. (2017). Design optimazation of aircraft landing gear assembly. Structural and Multidisciplinary Optimization.
[26] Zarchi, M., & Attaran, B. (2019). Improved design of an active landing gear for a passenger aircraft using multi-objective optimization technique. Structural and Multidisciplinary Optimization, 59(5), 1813–1833.
Cite This Article
  • APA Style

    Mwesigwa, I. I., Ndimila, B. W., Ramadhan, B. M. (2025). Mathematical Modelling and Simulation of a Two-Stage Nozzle Flapper Electro-Hydraulic Servo Valve for Aircraft Landing Gear Operation. American Journal of Aerospace Engineering, 11(2), 36-45. https://doi.org/10.11648/j.ajae.20251102.13

    Copy | Download

    ACS Style

    Mwesigwa, I. I.; Ndimila, B. W.; Ramadhan, B. M. Mathematical Modelling and Simulation of a Two-Stage Nozzle Flapper Electro-Hydraulic Servo Valve for Aircraft Landing Gear Operation. Am. J. Aerosp. Eng. 2025, 11(2), 36-45. doi: 10.11648/j.ajae.20251102.13

    Copy | Download

    AMA Style

    Mwesigwa II, Ndimila BW, Ramadhan BM. Mathematical Modelling and Simulation of a Two-Stage Nozzle Flapper Electro-Hydraulic Servo Valve for Aircraft Landing Gear Operation. Am J Aerosp Eng. 2025;11(2):36-45. doi: 10.11648/j.ajae.20251102.13

    Copy | Download

  • @article{10.11648/j.ajae.20251102.13,
      author = {Isaac Itekulana Mwesigwa and Benjamin William Ndimila and Bakari Momba Ramadhan},
      title = {Mathematical Modelling and Simulation of a Two-Stage Nozzle Flapper Electro-Hydraulic Servo Valve for Aircraft Landing Gear Operation
    },
      journal = {American Journal of Aerospace Engineering},
      volume = {11},
      number = {2},
      pages = {36-45},
      doi = {10.11648/j.ajae.20251102.13},
      url = {https://doi.org/10.11648/j.ajae.20251102.13},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajae.20251102.13},
      abstract = {Electro-hydraulic servo valves (EHSVs) are extensively used in aerospace actuation systems due to their capability to provide precise and rapid control of hydraulic flow. However, accurate mathematical modeling is essential to capture their complex nonlinear dynamics for purposes of simulation, analysis, and control system design. This paper presents a comprehensive mathematical model of a two-stage nozzle flapper EHSV applied to aircraft landing gear operations. The servo valve is divided into five key subsystems: the servo amplifier, voltage-current converter, torque motor, nozzle flapper mechanism, and spool valve integrated with a feedback sensor. Transfer functions are derived for each subsystem and subsequently combined to form an overall system model. The model’s accuracy is validated through simulations conducted in MATLAB/Simulink, enabling detailed performance analysis under various input conditions. Simulation results are used to evaluate system stability, transient response, and overall accuracy. The findings reveal a rapid settling time of 0.85 s, negligible overshoot, and a fine spool displacement of 1.43 × 10-4 m (0.143 mm), demonstrating the model’s capability to achieve stable and precise hydraulic control. These findings highlight the significant potential of the proposed mathematical model to enhance the dynamic performance of aircraft landing gear systems by providing more accurate, stable, and responsive control of hydraulic actuation.
    },
     year = {2025}
    }
    

    Copy | Download

  • TY  - JOUR
    T1  - Mathematical Modelling and Simulation of a Two-Stage Nozzle Flapper Electro-Hydraulic Servo Valve for Aircraft Landing Gear Operation
    
    AU  - Isaac Itekulana Mwesigwa
    AU  - Benjamin William Ndimila
    AU  - Bakari Momba Ramadhan
    Y1  - 2025/11/07
    PY  - 2025
    N1  - https://doi.org/10.11648/j.ajae.20251102.13
    DO  - 10.11648/j.ajae.20251102.13
    T2  - American Journal of Aerospace Engineering
    JF  - American Journal of Aerospace Engineering
    JO  - American Journal of Aerospace Engineering
    SP  - 36
    EP  - 45
    PB  - Science Publishing Group
    SN  - 2376-4821
    UR  - https://doi.org/10.11648/j.ajae.20251102.13
    AB  - Electro-hydraulic servo valves (EHSVs) are extensively used in aerospace actuation systems due to their capability to provide precise and rapid control of hydraulic flow. However, accurate mathematical modeling is essential to capture their complex nonlinear dynamics for purposes of simulation, analysis, and control system design. This paper presents a comprehensive mathematical model of a two-stage nozzle flapper EHSV applied to aircraft landing gear operations. The servo valve is divided into five key subsystems: the servo amplifier, voltage-current converter, torque motor, nozzle flapper mechanism, and spool valve integrated with a feedback sensor. Transfer functions are derived for each subsystem and subsequently combined to form an overall system model. The model’s accuracy is validated through simulations conducted in MATLAB/Simulink, enabling detailed performance analysis under various input conditions. Simulation results are used to evaluate system stability, transient response, and overall accuracy. The findings reveal a rapid settling time of 0.85 s, negligible overshoot, and a fine spool displacement of 1.43 × 10-4 m (0.143 mm), demonstrating the model’s capability to achieve stable and precise hydraulic control. These findings highlight the significant potential of the proposed mathematical model to enhance the dynamic performance of aircraft landing gear systems by providing more accurate, stable, and responsive control of hydraulic actuation.
    
    VL  - 11
    IS  - 2
    ER  - 

    Copy | Download

Author Information
  • Sections