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Autonomous helicopter hover positioning by optical tracking

Published online by Cambridge University Press:  04 July 2016

G. Bouwer
Affiliation:
DLR, Braunschweig, Germany
C-H. Oertel
Affiliation:
DLR, Braunschweig, Germany
W. von Grünhagen
Affiliation:
DLR, Braunschweig, Germany

Summary

The design of control systems for helicopters in hover and at low speed is a basic requirement for the extension of mission profiles and new mission demands. A special task for various applications is the position hold under wind and gust conditions above a ground fixed or moving target, like a shipboard reference, or a small vessel or lifeboat in rescue missions. For the solution of this problem a controller concept was developed and the feasibility was proven and successfully demonstrated in flight tests.

The in-flight helicopter simulator ATTHeS of the DLR has been equipped by the Institute of Flight Mechanics with an innovative measurement system for the hover position above a target. A video camera in combination with a highly parallel computer system for processing the optical information was used as an integra ted sensor system for the measurement of the relative position of the aircraft to a target. Based on the existing well-proven flight control laws of ATTHeS for the forward flight condition, which are implemented for handling qualities investigations, these control laws were modified and adapted to fulfil the special requirements of the position hold task, including altitude hold and heading hold capabilities. The integrated system of optical position sensor and control computer enables the helicopter to hover automatically above a defined target in constant altitude and with constant heading. Flight tests above a moving car under wind and gust conditions underline the future potential of the overall system to be used under operational conditions.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1995 

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References

1. ADS-33C, Aeronautical Design Standard, Handling Qualities Requirements for Military Rotorcraft, August, 1989.Google Scholar
2. Gold, P.J. and Dryfoos, J.B., Design and pilot evaluation of the RAH-66 Comanche selectable control modes, piloting vertical flight aircraft, A Conference on Flying Qualities and Human Factors, San Francisco, California, January 1993.Google Scholar
3. Menon, P.K.A., Chatterji, G.B. and Sridar, B. Vision based optimal obstacle-avoidance guidance for rotorcraft, AIAA-91-2755-CP.Google Scholar
4. Coppenbarger, R.A. and Cheng, V.H.L. Status of automated nap-of-the Earth rotorcraft guidance, AIAA-91-2756-CP.Google Scholar
5. AGARD Lecture Series 185 on Machine Perception, August 1992.Google Scholar
6. Dickmanns, E.D. and Graefe, V. a) Dynamic monocular machine vision, b) Application of dynamic monocular machine vision, J Machine Vision & Application, Springer-Int, Nr 1388, pp 223261.Google Scholar
7. Cook, M.V. and Rycroft, M.J. Aerospace Vehicle Dynamics and Control, Clarendon Press, Oxford, 1994.Google Scholar
8. Bouwer, G. The application of model following control to helicopter tracking tasks — Part 1 : Simulation, DLR Institute Report IB 111-91/23, 1991.Google Scholar
9. Von Grünhagen, W. et al A High Bandwidth Control System for a Helicopter In-Flight Simulaton, Int J of Control, Taylor & Francis, London/Washington, 1993, pp 239261.Google Scholar
10. Kuhnert, K.D. Zur Echtzeit-Bildfolgenanalyse mit Vorwissen, Dissertation, Fakultät für Luft- und Raumfahrttechnik der Universität der Bundeswehr München, 1988.Google Scholar
11. Fu, K.-H. and Kaletka, J. BO 105 System Identification for Hover Flight Condition, 19th European Rotorcraft Forum, Cernobbio (Como), Italy, September 1993.Google Scholar
12. Saager, P.and Von Grünhagen, W. Realtime helicopter simulation, International Symposium on Simulation, INFAUTUM 89, Toulouse, France, 1989.Google Scholar
13. Alvermann, K. Visualization and view simulation based on transputers, J of Aircr, 30, (4), 1993.Google Scholar