DOI QR코드

DOI QR Code

Inflow Prediction and First Principles Modeling of a Coaxial Rotor Unmanned Aerial Vehicle in Forward Flight

Harun-Or-Rashid, Mohammad;Song, Jun-Beom;Byun, Young-Seop;Kang, Beom-Soo

  • Received : 2015.04.20
  • Accepted : 2015.12.20
  • Published : 2015.12.30

Abstract

When the speed of a coaxial rotor helicopter in forward flight increases, the wake skew angle of the rotor increases and consequently the position of the vena contracta of the upper rotor with respect to the lower rotor changes. Considering ambient air and the effect of the upper rotor, this study proposes a nonuniform inflow model for the lower rotor of a coaxial rotor helicopter in forward flight. The total required power of the coaxial rotor system was compared against Dingeldein's experimental data, and the results of the proposed model were well matched. A plant model was also developed from first principles for flight simulation, unknown parameter estimation and control analysis. The coaxial rotor helicopter used for this study was manufactured for surveillance and reconnaissance and does not have any stabilizer bar. Therefore, a feedback controller was included during flight test and parameter estimation to overcome unstable situations. Predicted responses of parameter estimation and validation show good agreement with experimental data. Therefore, the methodology described in this paper can be used to develop numerical plant model, study non-uniform inflow model, conduct performance analysis and parameter estimation of coaxial rotor as well as other rotorcrafts in forward flight.

Keywords

blade element theory;coaxial rotor;forward flight;nonuniform inflow

References

  1. Leishman, J.G., Principles of Helicopter Aerodynamics, Cambridge University press, New York, 2006.
  2. Chen, R.T.N., "A Survey of Nonuniform Inflow Models for Rotorcraft Flight Dynamics and Control Applications," NASA Technical Memorandum 102219, 1989.
  3. Mettler, B., Tischler, M.B. and Kanade, T., System identification of small-size unmanned helicopter dynamics, Journal of the American Helicopter Society, Vol. 47, No. 1, 2002, pp. 50-63. https://doi.org/10.4050/JAHS.47.50
  4. Raptis, A. and Valavanis, P., Linear and nonlinear control of small-scale unmanned helicopters, Springer, New York, 2011.
  5. Kenneth, W.L., "Aircraft Parameter Estimation," NASA Technical Memorandum 88281, 1987.
  6. Abas, N., Legowo, A. and Akmeliawati, R., "Parameter Identification of an Autonomous Quad rotor," 4th International Conference on Mechatronics, Kuala Lumpur, 2011.
  7. Schafroth, D., Bermes, C., Bouaddallah, S. and Siegwart, R., "Modeling, system identification and robust control of a coaxial micro helicopter," Control Engineering Practice, Vol. 18, 2010, pp. 700-711. https://doi.org/10.1016/j.conengprac.2010.02.004
  8. Ho-Chan Kim et al., "Parameter Identification and Design of a Robust Attitude Controller Using H Methodology for the Raptor E620 Small-Scale Helicopter," International Journal of Control, Automation, and Systems, Vol. 10, No. 1, 2012, pp. 88-101. https://doi.org/10.1007/s12555-012-0110-5
  9. Baoquan Song et al., "Dynamic Modeling and Control of a Small-Scale Helicopter," International Journal of Control, Automation, and Systems, Vol. 8, No. 3, 2010, pp. 534-543. https://doi.org/10.1007/s12555-010-0306-5
  10. Leishman, J.G. and Ananthan, S., "Aerodynamics optimization of a coaxial prop rotor," Proceedings of 62nd Annual National Forum of the American Helicopter Society, Phoenix, AZ, 2006.
  11. Prouty, R. W., Helicopter Performance, Stability, and Control, Robert E. Krieger Publishing Company, Florida, 1990.
  12. Elliott, J. W., Althoff, S. L. and Sailey, R. H., 1988, Inflow Measurements Made with a Laser Velocimeter on a Helicopter Model in Forward Flight," In three Volumes: volume I: Rectangular plan form at an Advance Ratio of 0.15, NASA TM 100541. Volume II: Rectangular plan form at an Advance Ratio of 0.23, NASA TM 100542. Volume III: Rectangular plan form at an Advance Ratio of 0.23, NASA TM 100543.
  13. Harrington, R.D., "Full-scale tunnel investigation of the static thrust performance of a coaxial helicopter rotor," NACA Technical Note 2318, 1951.
  14. Dingeldein, R.C., "Wind tunnel studies of the performance of a multi rotor configurations," NACA Technical Note 3236, 1954.
  15. Ledin, J., Embedded Control Systems in C/C++, CMP Books; New York, 2004.
  16. Astrom, K.J. and Hagglund, T., PID Controllers: Theory, Design, and Tuning, Instrument Society of America, North Carolina, 1995.
  17. Prasenjit, M. and Steven, L. W., "Modeling and Multivariable Control Technique for Small Coaxial Helicopters," AIAA Guidance Navigation, and Control Conference, Portland, August 2011.
  18. J Alejandro, M. T., "Dynamic model for a Coaxial- UAV," AIAA Modeling and Simulation Technologies (MST) Conference, Boston, August 2013.
  19. Mettler, B., Identification modelling and characteristics of miniature rotorcraft, Kluwer Academic Publishers, Boston, 2003.
  20. Xin-She, Y. and Kozielm, S., Computational optimization, methods and algorithms, Springer, Verlag, 2011.
  21. Harun-Or-Rashid, M., et al., "Unmanned coaxial rotor helicopter dynamics and system parameter estimation", Journal of Mechanical Science and Technology, Vol. 28, No. 9, 2014, pp. 3797-3805. https://doi.org/10.1007/s12206-014-0842-7
  22. Bramwell, A.R.S., Done, G. and Balmford, D., Bramwell's Helicopter Dynamics, 2nd ed., Butterworth-Heinemann, Oxford, 2001.

Cited by

  1. Computational Investigation on Unsteady Loads of High-Speed Rigid Coaxial Rotor with High-Efficient Trim Model pp.2093-2480, 2019, https://doi.org/10.1007/s42405-018-0133-0

Acknowledgement

Supported by : National Research Foundation of Korea (NRF)