Hostname: page-component-76fb5796d-qxdb6 Total loading time: 0 Render date: 2024-04-28T06:02:04.857Z Has data issue: false hasContentIssue false

Methods for accurate measurements of small fixed wing UAV inertial properties

Published online by Cambridge University Press:  11 November 2016

K. Lehmkühler*
Affiliation:
School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, Australia
K.C. Wong
Affiliation:
School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, Australia
D. Verstraete
Affiliation:
School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, Australia

Abstract

Two methods have been compared for the determination of the inertial properties of a small, fixed-wing un-manned aerial vehicle. The first method uses the standard single degree of freedom pendulum method and the second method implements a novel, potentially easier, 3 degrees of freedom pendulum method, which yields the entire inertia tensor from a single swing test. Both methods are using system identification of the pendulum motion to estimate the inertial properties. Substantial corrections (up to 25%) have to be applied to the experimental results. These corrections are caused by the acceleration of the pendulum being immersed in the surrounding air, also called the added mass effect. It has been found that the methods presented in literature to determine the corrections for full-scale aircraft do not give the correct results for the small-scale un-manned aerial vehicle under consideration. The only feasible, cost-effective method to generate these corrections utilise swing tests with a geometrically similar object of known inertial properties. It has also been found that the corrections are unique with respect to the experimental methods. Several benchmarking methods, including the innovative use of static and dynamic wind-tunnel test data, give high confidence in the results.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2016 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Meier, L., Honegger, D. and Pollefeys, P. Px4: A node-based multithreaded open source robotics framework for deeply embedded platforms, ICRA Conference, 2015.CrossRefGoogle Scholar
2. Schedlinski, C. and Link, M. A survey of current inertia parameter identification methods, Mech. Systems and Signal Processing, 2001, 15, (1), 189211. doi:1006/mssp.2000.1345.CrossRefGoogle Scholar
3. de Jong, R.C. and Mulder, J.A. Accurate estimation of aircraft inertia characteristics from a single suspension experiment, J. Aircraft, 1987, 24, (6), 362370.CrossRefGoogle Scholar
4. Brancati, R., Russo, R. and Savino, S. Method and equipment for inertia parameter identification, Mech. Systems and Signal Processing, 2010, 24, (1), 2940.CrossRefGoogle Scholar
5. Korr, A.L. and Hyer, P. A trifilar pendulum for the determination of moments of inertia, Armed Services Technical Information Agency Report, AD 287 534, 1962.CrossRefGoogle Scholar
6. Previati, G., Gobbi, M. and Mastinu, G. Method for the measurement of the inertia properties of bodies with aerofoils, J. Aircraft, 2012, 49, (2), 444452.CrossRefGoogle Scholar
7. Miller, M.P. An accurate method of measuring the moments of inertia of airplanes, NACA TN-351, 1930.Google Scholar
8. Soule, H.A. and Miller, M.P. The experimental determination of the moments of inertia of airplanes, NACA Report No. 467, 1934.Google Scholar
9. Gracey, W. The experimental determination of the moments of inertia of airplanes by a simplified compound -pendulum method, NACA TN 1629, 1948.Google Scholar
10. Turner, H.L. Measurement of the moments of inertia of an airplane by a simplified method, NACA TN 2201, 1950.Google Scholar
11. Shakoori, A., Betin, A.V. and Betin, D.A. Comparison of three methods to determine the inertial properties of free-flying dynamically similar models, J. Engineering Science and Technology, accessed 21/03/2016. URL jestec.taylors.edu.my/Articles%20in%20Press/11_10_1.pdf.Google Scholar
12. Patankar, S.S., Schinstock, D.E. and Caplinger, R.M. Application of pendulum method to uav momental ellipsoid estimation, 6th AIAA Aviation Technology, Integration and Operations Conference (ATIO), 2006, Wichita, Kansas, US.CrossRefGoogle Scholar
13. Bussamra, F., Vilchez, C. and Santos, J. Experimental determination of unmanned aircraft inertial properties, Proceedings of 3rd CTA-DLR Workshop on Data Analysis and Flight Control, 14-16 September 2009, S. J. Campos, SP, Brazil.Google Scholar
14. Jardin, M.R. and Mueller, E.R. Optimized measurements of uav mass moment of inertia with a bifilar pendulum, AIAA Guidance, Navigation and Control Conference and Exhibit, 2007, Hilton Head, South Carolina, US.CrossRefGoogle Scholar
15. Kotikalpudi, A., Taylor, B., Moreno, C., Pfifer, H. and Balas, G.J. Swing tests for estimation of moments of inertia, accessed 20/03/2016. URL https://conservancy.umn.edu/bitstream/handle/11299/167676/BFF%20Moment%20of%20Inertia%20Testing.pdf?sequence=1&isAllowed=y.Google Scholar
16. Mendes, A.S., van Kampen, E., Remes, B.D.W. and Chu, Q.P. Determining moments of inertia of small uavs: A comparative analysis of an experimental method versus theoretical approaches, AIAA Guidance, Navigation, and Control Conference, 2012, Minneapolis, Minnesota, US.CrossRefGoogle Scholar
17. Bottasso, C.L., Leonello, D., Maffezzoli, A. and Riccardi, F. A procedure for the identification of the inertial properties of small-size uavs, XX AIDAA Congress Milano, 2009.Google Scholar
18. Lupton, R. Measuring tidal Variations in g Using Trinitys Pendulum Clock, Thesis, Cranfield University, Cranfield, UK, accessed: 15.02.2014. URL trin-hosts.trin.cam.ac.uk/clock/theory/pendulum.pdf.Google Scholar
19. Klein, V. and Morelli, E.A. Aircraft System Identification, 2006, AIAA.CrossRefGoogle Scholar
20. Brennen, C.E. A review of added mass and fluid inertial forces, Naval Civil Engineering Laboratory Report, 1982.Google Scholar
21. Lin, Z. and Liao, S. Calculation of added mass coefficients of 3D complicated underwater bodies by FMBEM, Communications in Nonlinear Science and Numerical Simulation, 2011, 16, (1), 187194.CrossRefGoogle Scholar
22. Malvestuto, F.S. and Gale, L.J. Formulas for additional mass corrections to the moments of inertia of airplanes, NACA TN-1187, 1947.Google Scholar
23. Gracey, W. The additional mass effect of plates as determined by experiments, NACA Report 707, 1941.Google Scholar
24. Carpenter, P. Rc airplane world, accessed:15/7/2015. URL http://www.rc-airplane-world.com/model-airplane-kits.HTML.Google Scholar
25. Lennon, A. R/C Model Aircraft Design, AirAge Media, 1996. URL modelairplanenews.com.Google Scholar
26. Siegmann, H. Aerodesign. accessed: 15.3.2012. URL www.aerodesign.de.Google Scholar
27. VectorNav. Vn-100 smd. accessed: 21/8/2015. URL http://www.vectornav.com/products/vn100-smd.Google Scholar
28. Gusev, N.A. Determination of gravity acceleration at sydney with pendulum apparatus, Bureau of Mineral Resources, Geology And Geophysics, Record 1973/115, 1973.Google Scholar
29. Carnduff, S. System Identification of Unmanned Aerial Vehicles, Thesis, Cambridge University, Cambridge, US, 2008.Google Scholar
30. Carnduff, S.D. and Cooke, A.K. Formulation and system identification of the equations of motion for a dynamic wind tunnel facility, College of Aeronautics Report No. 0801, 2008, Cranfield.Google Scholar
31. Raymer, D. Aircraft Design: A Conceptual Approach, 2012, AIAA.CrossRefGoogle Scholar