Dynamics Model of Carrier-based Aircraft Landing Gears Landed on Dynamic Deck

In this work, we demonstrate the use of co-simulation technology in the maritime industry through four relevant examples of applications based on the outcome of the knowledge-building project Virtual Prototyping of Maritime Systems and Operations (ViProMa). Increasing computational capabilities opens for extended use of simulators in the design processes. Even complex systems can now be analyzed at an early stage of the design process and even in real time using distributed simulation technology. We conduct an assessment of the need for co-simulation technology in the industry, present a short background in co-simulation technology, and provide a short summary of the major findings and deliverables in the ViProMa project (
 http://viproma.no
 ). The four case studies presented in this work pinpoint different advantages of using co-simulations in the industry, such as combining different modeling and simulation tools, improving collaboration without revealing sensitive information by using black-box models, testing conceptual designs in a fast and consistent manner before initiating building processes, and verifying the interplay between hardware and software in the simulation environment in hardware in the loop (HIL) tests. All the case studies are simulated using the open source co-simulation software Coral developed in the project, using the Functional Mock-up Interface (FMI) standard, and the co-simulation software can be downloaded from the project’s web site.

Virtual prototyping of maritime systems and operations: applications of distributed co-simulations

In this paper a dynamic simulation methodology of systems is presented by using ADAMS/MATLAB co-simulation. This methodology allows simulation, development and validation of different control strategiesfor robotic manipulator models in a fast way. It provides a first stage into the design of robotic prototypes for researchers and professionals. Finally, the methodology was validated by constructing a simulation model of a double pendulum and by implementing a PD type control strategy.

ADAMS/MATLAB Co-Simulation: Dynamic Systems Analysis and Control Tool

A key part of the main landing gear of a civil aircraft is its locking mechanism that holds the gear in the deployed or downlocked state. The locking is driven by a spring mechanism and its release...

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Optimization of a main landing gear locking mechanism using bifurcation analysis

In order to improve aircraft ground handling characteristics and airport working efficiency, large handling angle and torque are requested for the nose wheel steering system of large civil aircraft. A following swivel selector valve is firstly designed to meet the demand for the hydraulic pressure commutating as soon as the dual actuator nose wheel steering mechanism passes through its dead center position. Considering the multiple objective functions of nose wheel steering mechanisms, those core design parameters are multiobjective optimized. A nose wheel steering electrohydraulic servo system with handling and antishimmy functions is designed for the steering mechanism. Then the prototypes of the steering mechanism and electrohydraulic servo system are researched to validate the design. Using the swing actuator to provide the load torque and ground excitation, the steering test bench is prepared to test the system working. The steering test and the antishimmy test are conducted to verify the functions of the system. The test results, such as steer angle, steer torque hydraulic pressure, and antishimmy torque, are analyzed in detail and compared with the theoretical results. The results show that the property of the prototype achieves the design objectives, such as work mode, steer angle, and steer torque.

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Design and Test of Dual Actuator Nose Wheel Steering System for Large Civil Aircraft

Purpose – The purpose of this paper is to introduce a co‐simulation method to study the ground maneuvers of aircraft anti‐skid braking and steering.Design/methodology/approach – A virtual prototype of aircraft is established in the multibody system dynamics software MSC.ADAMS/Aircraft. The anti‐skid braking control model, which adopts the multi‐threshold PID control method with a slip‐velocity‐controlled, pressure‐bias‐modulated (PBM) system, is established in MATLAB/Simulink. EASY5 is used to establish the hydraulic system of nose wheel steering. The ADAMS model is connected to block diagrams of the anti‐skid braking control model in MATLAB/Simulink, and is also connected to the block diagrams of nose wheel steering system model in EASY5, so that the ground maneuvers of aircraft anti‐skid braking and steering are simulated separately.Findings – Results are presented to investigate the performance of anti‐skid braking system in aircraft anti‐skid simulation. In aircraft steering simulation, the influence ...

Modeling and simulation of aircraft anti‐skid braking and steering using co‐simulation method

The landing gear retraction system of an aircraft, including mechanical and hydraulic systems, is complex and nonlinear. It has many uncertain factors, which lead to difficulty in reliability analysis. To make the reliability analysis more accurate and efficient, some studies are represented in this paper. Taking the main landing gear of an aircraft as a research object, the dynamic equations of the retraction system were derived. The simulation model was built, combining the mechanism dynamics with the hydraulic system, and its accuracy was verified by laboratory test results. Based on this model, the paper shows how the key parameters, including the crosswind velocity, the diameter of the damping orifice, liquid capacity, friction, and oil leak, affect the performance of the landing gear retraction. After that, the limit state equation of the retraction system’s reliability was set up. For the implicit limit state equation, the response surface model of retraction reliability was established with a quad...

Reliability Analysis of Landing Gear Retraction System Influenced by Multifactors

The conception of landing area is introduced to the aircraft carrier, and a simplified model of the conventional oleo-pneumatic landing gear during the process of landing impact on the landing area is established. The mathematic model is also derived. The dynamic response of the landing gear landing vertically is calculated via Runge-Kutta procedure. Simulation results for both the original model and the new model are presented to illustrate the effectiveness of the new model. The result shows that the maximum of the impact loads on airframe and the maximal ground reaction force are reduced 37.3% and 37.2% respectively.

New Method of Attenuating Landing Impact Force on Carrier-based Aircraft Landing Gear

In this paper, the fault analysis of an aircraft nose landing gear’s emergency lowering was conducted with a cosimulation method. The simulation was aimed at studying the dynamic response characteristics of landing-gear retraction/extension. Moreover, the equations of the mechanical and hydraulic system were derived and analyzed so as to acquire the boundary condition under which the landing-gear emergency lowering could fail. Based on the simulation platform computer aided engineering, a cosimulation model (including a dynamic system and a hydraulic system) was developed, after which, by comparing the simulation results with the data of the ground test and flight test, the model was further verified. Additionally, the nose landing gear could succeed in emergency lowering with the premise that the critical dampings of different flight cases and temperatures were obtained. After that, a feasible scheme of emergency lowering was put forward. The results showed that, at the end of the landing-gear lowering p...

Fault Analysis and Solution of an Airplane Nose Landing Gear’s Emergency Lowering

In this study, the fatigue life prediction in hypersonic vehicle noise environment is researched under the structural vibration caused by the engine jet noise and the aerodynamic noise. A finite element analysis model is first established, and then natural frequency and vibration mode are obtained. According to the modal analysis, the vibroacoustic coupling calculation is finished in the dynamic analysis software. Modal participation factor, modal displacement, and the power spectral density of the stress response on the coupled surface are acquired. The finite element, border component, and vibrating stress analytical techniques are also employed in this research to predict the acoustical fatigue performance of the tail fins of a specific type of spacecraft. On the basis of vibration fatigue theory, identified material S–N curve, and linear cumulative damage theory, the Dirlik model in the frequency domain method for vibration fatigue is used to predict the fatigue life of empennage. According to the characteristics of the acoustic load, effects of the load characteristics, and damping ratios on the fatigue conditions, the design of the antifatigue design is put forward.

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Nie Hong

Papers

Modeling and simulation of aircraft anti‐skid braking and steering using co‐simulation method

Reliability Analysis of Landing Gear Retraction System Influenced by Multifactors

New Method of Attenuating Landing Impact Force on Carrier-based Aircraft Landing Gear

Fault Analysis and Solution of an Airplane Nose Landing Gear’s Emergency Lowering

Analysis on Vibroacoustic Fatigue Life of Empennage in a Hypersonic Vehicle