Toward Automated Gust Load Alleviation Control Design via Discrete Gust Impulse Filters

Abstract

In the context of active gust- and turbulence-load alleviation function design, control designers optimize the response of the closed-loop system to satisfy the relevant certification specifications (e.g., European Union Aviation Safety Agency (EASA) CS-25.341 and Federal Aviation Regulations (FAR) Part 25, Sec. 341). These include time-domain criteria specifying the peak response to discrete gusts as well as frequency-domain continuous-turbulence criteria. Both types of criteria cannot be easily considered simultaneously with commonly available control design software. A frequency-domain formulation of 1--cosine discrete gust criteria based on a low-order, parameterized linear filter is proposed and demonstrated on a publicly available gust load alleviation benchmark. One example demonstrates its application in combination with continuous-turbulence specifications, and in principle, it can also be combined with other relevant frequency-domain specifications, such as passenger comfort metrics. This technique is shown to work well, producing the desired results with a simple, systematic design procedure, and should help reduce the time and effort required to obtain satisfactory control specifications.