Towards Simultaneous Performance: Application of Simultaneous Stabilization Techniques to Helicopter Engine Control

Despite the impact that the Stable Factorization (SF) approach has had on the academic community, its widespread acceptance and application by industry has been hampered by the natural lag in the development of design algorithms and their associated numerically reliable CAD implementations. Indeed, it is safe to say that computer-aided design support for the Stable Factorization methodology (and in fact, many of the principle design algorithms) have not as yet matured to the point where they may be readily applied by practising engineers. In this paper we describe on-going research aimed at refining one such design algorithm, namely simultaneous stabilization. Through application of the simultaneous stabilization design technique to a realistic aerospace control problem we seek to demonstrate the practical utility of the method, and identify the technical issues that remain to be resolved. The focus of this study is the GE T700 turboshaft engine, when coupled to the Apache and Blackhawk helicopter airframes. We describe our experiences with an indirect design technique to obtain an LTI compensator that simultaneously satisfies two loop-shaping type performance criteria, one for each engine-airframe combination.