Surrogate Models for Helicopter Loads Problems (in English)
Burnaev E., Prikhodko P., Struzik A.
Proceedings of 5th European Conference for Aerospace Sciences
One of the activities of the EUROCOPTER flight test department is to measure loads for different components (through load gauges) and flight configurations. In this paper, a flight configuration includes both the manoeuvre and general information about the helicopter itself (helicopter weights, longitudinal/lateral centre of gravity locations, altitudes) and the air characteristics in which the helicopter is flying (Outside Air Temperature). A flight configuration is described by the Flight Configuration Parameters (FCP). Information, obtained from this activity, is stored in a specific database. In the scope of CHAMALO (acronym of Calculation of Helicopter Approximated MAcros LOads) project, EUROCOPTER is interested in building surrogate models from the existing load database to estimate missing loads from FCP. Both the objective and challenge is to automatically build accurate and robust surrogate models from the load database, which explain the relations between the input FCP and the output static and dynamic loads. MACROS tool (developed by DATADVANCE) is used for surrogate modelling. This tool includes a wide range of well-known techniques (e.g., Splines, Linear Regression, Gaussian Process Regression), original techniques (e.g., HDA - High Dimensional Approximation), an automatic selection of the appropriate approximation type based on built-in decision tree and data properties, and a flexible support for accelerated training, smoothing, handling multiple output components, etc. Once the best surrogate models for each load gauge (66 in total) and manoeuvre family (32 in total) were constructed, CHAMALO software was developed by DATADVANCE for automatic prediction of helicopter static and dynamic loads as a function of FCP. It is concluded that EUROCOPTER considers this approach to be very promising. In fact, about 50% of missing loads, which need to be estimated, may be calculated by CHAMALO with a sufficient accuracy, drastically reducing the time and manpower needed for such analysis. Further studies are planned to increase this percentage.