Abstract
A typical oleo-pneumatic shock-absorbing strut (classic traditional passive damper) in aircraft landing gear has a metering pin extending through the orifice, which can vary the orifice area with the compression and extension of the damper strut. Because the metering pin is designed in a single landing condition, the traditional passive damper cannot adjust its damping force in multiple landing conditions. Magnetorheological (MR) dampers have been receiving significant attention as an alternative to traditional passive dampers. An MR damper, which is a typical semi-active suspension system, can control the damping force created by MR fluid under the magnetic field. Thus, it can be controlled by electric current. This paper adopts a neural network controller trained by two different methods, which are genetic algorithm and policy gradient estimation, for aircraft landing gear with an MR damper that considers different landing scenarios. The controller learns from a large number of trials, and accordingly, the main advantage is that it runs autonomously without requiring system knowledge. Moreover, comparative numerical simulations are executed with a passive damper and adaptive hybrid controller under various aircraft masses and sink speeds for verifying the effectiveness of the proposed controller. The main simulation results show that the proposed controller exhibits comparable performance to the adaptive hybrid controller without any needs for the online estimation of landing conditions.
Highlights
Magnetorheological (MR) dampers have been studied in a wide range of industrial fields to effectively control and reduce unwanted vibrations [1]
It can be seen that PGE-NN converts at
Nt ΔGj is defined as the average of the random directions [27], which is given by: Figure 8 shows the simulation results of GA-NN with different neurons fr m
Summary
Magnetorheological (MR) dampers have been studied in a wide range of industrial fields to effectively control and reduce unwanted vibrations [1]. The application of an MR damper as a replacement for a traditional oleo-strut (i.e., oleo-pneumatic damper) is very uncommon in aircraft landing gears [2]. The traditional oleo-strut, which has an orifice area that varies according to the movement of the metering pin, limits the efficiency of the damper, especially for conditions other than where it is designed, because only a slight change in the viscous damping force can be made. A landing gear equipped with an MR damper, which is the most plausible replacement for the oleo-strut, has such advantages as quick response times, reduced weight, and lower costs [3,4]. The development of a controller for an MR damper is a challenging problem
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
