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Time-delay compensation in active control algorithms

Published online by Cambridge University Press:  04 July 2016

A. Bradshaw
Affiliation:
Department of Aeronautical and Mechanical Engineering, University of Salford
M. A. Woodhead
Affiliation:
Department of Aeronautical and Mechanical Engineering, University of Salford

Summary

In this paper a direct digital control law algorithm is proposed which in addition to providing tight non-interacting tracking behaviour and excellent disturbance-rejection characteristics, provides for the compensation of finite-time delays in implementation. The control-law algorithm is defined and system stability is proved in the case of multi-input multi-output linear systems. The theory is synthetic and leads directly to the determination of the appropriate controller matrices.

The theory is illustrated by the presentation of simulation results in which the aircraft is represented by an analogue computer and the digital control system is implemented on a microprocessor. In the simulation study the controller is required to effect fuselage pitch pointing and vertical translation manoeuvres for the analogue computer representation of the YF-16 aircraft. It is shown that tight non-interacting control is achievable even when the control implemented is delayed by 0·1 seconds.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1985 

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References

1. Bradshaw, A. and Porter, B. Singular perturbation methods in the design of tracking systems incorporating fast-sampling erroractuated controllers, Int J Systems Sci, 1981, 12, 11811191.Google Scholar
2. Bradshaw, A. and Porter, B. Singular perturbation methods in the design of tracking systems incorporating inner-loop compensators and fast-sampling error-actuated controllers, Int J Systems Sci, 1981, 12. 12071220.Google Scholar
3: Porter, B. and Bradshaw, A. Design of direct digital flight-mode ontrol systems for high-performance aircraft, Proc IEEE National Aerospace and Electronics Conference, Dayton, USA, May 1981.Google Scholar
4. Porter, B., Bradshaw, A., Garis, A. and Woodhead, M. A.France, 9th-14tn September 1984. Microprocessor implementation of fast-sampling direct digital flight-mode controllers, AGARD-CP-321, ‘Advances in Guidance and Control Systems’, Lisbon, Portugal, October 1982.Google Scholar
5. Butler, G. F., Corbin, M. J., Mepham, S., Stewart, J. F. and Larson, R. R. NASA/RAE Collaboration on Non-linear Control using the F-8C Digital Fly-by-Wire Aircraft, AGARD/NATO Conference on Advances in Guidance and Control Systems, AGARD-CP-321, Lisbon, Portugal, October 1982.Google Scholar
6. McRuer, D. Progress and pitfalls in advanced flight control systems, AGARD-CP-321, Lisbon, Portugal, October 1982.Google Scholar
7. Koepcke, R. W. On the control of linear systems with pure time-delay. Trans ASME J of Basic Engineering, 1965, 87. 7480.Google Scholar