scholarly journals Vibration Attenuation of Magnetorheological Landing Gear System with Human Simulated Intelligent Control

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
X. M. Dong ◽  
G. W. Xiong
Keyword(s):  
Intelligent Control ◽  
Control Algorithm ◽  
Impact Load ◽  
Landing Gear ◽  
Gear System ◽  
Control Parameters ◽  
Vibration Attenuation ◽  
Adaptive Ability ◽  
The Impact ◽  
Two Degree Of Freedom

Due to the short duration of impulsive impact of an aircraft during touchdown, a traditional landing gear can only achieve limited performance. In this study, a magnetorheological (MR) absorber is incorporated into a landing gear system; an intelligent control algorithm, a human simulated intelligent control (HSIC), is proposed to adaptively tune the MR absorber. First, a two degree-of-freedom (DOF) dynamic model of a landing gear system featuring an MR absorber is constructed. The control model of an MR damper is also developed. After analyzing the impact characteristic during touchdown, an HSIC is then formulated. A genetic algorithm is adopted to optimize the control parameters of HSIC. Finally, a numerical simulation is performed to validate the proposed damper and the controller considering the varieties of sink velocities and sprung masses. The simulations under different scenarios show that the landing gear system based on the MR absorber can greatly reduce the peak impact load of sprung mass within the stroke. The biggest improvement of the proposed controller is over 40% compared to that of skyhook controller. Furthermore, HSIC exhibits better adaptive ability and strong robustness than skyhook controller under various payloads and sink velocities.

scholarly journals A Rational Numerical Method for Simulation of Drop-Impact Dynamics of Oleo-Pneumatic Landing Gear

2021 ◽  
Vol 11 (9) ◽  
pp. 4136
Author(s):  
Rosario Pecora
Keyword(s):  
Numerical Method ◽  
Initial Conditions ◽  
Impact Load ◽  
Numerical Models ◽  
Landing Gear ◽  
Design Stage ◽  
Impact Dynamics ◽  
State Variables ◽  
Adopted Model ◽  
The Impact

Oleo-pneumatic landing gear is a complex mechanical system conceived to efficiently absorb and dissipate an aircraft’s kinetic energy at touchdown, thus reducing the impact load and acceleration transmitted to the airframe. Due to its significant influence on ground loads, this system is generally designed in parallel with the main structural components of the aircraft, such as the fuselage and wings. Robust numerical models for simulating landing gear impact dynamics are essential from the preliminary design stage in order to properly assess aircraft configuration and structural arrangements. Finite element (FE) analysis is a viable solution for supporting the design. However, regarding the oleo-pneumatic struts, FE-based simulation may become unpractical, since detailed models are required to obtain reliable results. Moreover, FE models could not be very versatile for accommodating the many design updates that usually occur at the beginning of the landing gear project or during the layout optimization process. In this work, a numerical method for simulating oleo-pneumatic landing gear drop dynamics is presented. To effectively support both the preliminary and advanced design of landing gear units, the proposed simulation approach rationally balances the level of sophistication of the adopted model with the need for accurate results. Although based on a formulation assuming only four state variables for the description of landing gear dynamics, the approach successfully accounts for all the relevant forces that arise during the drop and their influence on landing gear motion. A set of intercommunicating routines was implemented in MATLAB® environment to integrate the dynamic impact equations, starting from user-defined initial conditions and general parameters related to the geometric and structural configuration of the landing gear. The tool was then used to simulate a drop test of a reference landing gear, and the obtained results were successfully validated against available experimental data.

A novel retractable landing gear of a light amphibious airplane design, synthesis, analysis, and implementation

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sinchai Chinvorarat ◽  
Pumyos Vallikul
Keyword(s):  
Impact Load ◽  
Landing Gear ◽  
Drop Test ◽  
Drop Height ◽  
Core Element ◽  
Design Synthesis ◽  
Content Type ◽  
And Performance ◽  
Correct Path ◽  
The Impact

Purpose The purpose of this paper is to present a novel retractable main landing gear for a light amphibious airplane, while the design, synthesis and analysis are given in details for constructing the main landing gear. Design/methodology/approach The constraint three-position synthesis has given the correct path of all linkages that suitably fit the landing gear into the compartment. The additional lock-link is introduced into the design to ensure the securement of the mechanism while landing. Having the telescopic gas-oil shock strut as a core element to absorb the impact load, it enhances the ability and efficiency to withstand higher impact than others type of light amphibious airplane. Findings By kinematics bifurcation analysis, the optimized value of the unlock spring stiffness at 90 N/m can be found to tremendously reduce the extended-retracted linear actuator force from 500 N to 150 N at the beginning of the retraction sequence. This could limit the size and weight of the landing gear actuator of the light amphibious airplane. Practical implications The drop test of the landing gear to comply with the ASTM f-2245 (Standard Specification for Design and Performance of a Light Sport Airplane) reveals that the novel landing gear can withstand the impact load at the drop height determined by the standard. The maximum impact loading 4.8 G occurs at the drop height of 300 mm, and there is no sign of any detrimental or failure of the landing gear or the structure of the light amphibious airplane. The impact settling time response reaches the 2% of steady-state value in approximately 1.2 s that ensure the safety and stability of the amphibious airplane if it subjects to an accidentally hard landing. Originality/value This paper presents unique applications of a retractable main landing gear of a light amphibious airplane. The proposed landing gear functions properly and complies with the drop test standard, ensuring the safety and reliability of the airplane and exploiting the airworthiness certification process.

The Wet Clutch Pressure Control of Dual Clutch Transmission Based on FCMAC

2012 ◽  
Vol 157-158 ◽  
pp. 1614-1619
Author(s):  
Yin Shu Wang ◽  
Xiu Sheng Cheng ◽  
Yong Dao Song ◽  
Peng Han
Keyword(s):  
Control System ◽  
Intelligent Control ◽  
Control Algorithm ◽  
Pressure Control ◽  
Cerebellar Model Articulation Controller ◽  
Dual Clutch Transmission ◽  
Intelligent Control System ◽  
Wet Clutch ◽  
Pressure Control System ◽  
Adaptive Ability

A wet clutch pressure control system of dual clutch transmission was presented in this paper, and clutch pressure intelligent control arithmetic based on FCMAC(Fuzzy Cerebellar Model Articulation Controller) was designed to realize accracy control of clutch pressure. The intelligent control system was verified by experiment, and the rusults showed that the clutch intelligent control algorithm with FCMAC had good adaptive ability and high precision. It could meet the requirements of the clutch peressure contol of DCT.

Effect of the Impact Load on the Main Welding Outer Cylinder of Large Aircraft Landing Gear

2013 ◽  
Vol 567 ◽  
pp. 169-173
Author(s):  
Hong Feng Wang ◽  
W.W. Song ◽  
J.L. Wang ◽  
Dun Wen Zuo ◽  
X.L. Duan
Keyword(s):  
Life Prediction ◽  
Impact Load ◽  
Outer Cylinder ◽  
Element Model ◽  
Landing Gear ◽  
Aircraft Landing ◽  
Aircraft Landing Gear ◽  
The Impact ◽  
Important Basis ◽  
Large Aircraft

Analysis about the cause of the main failure and the forces of the main welding outer cylinder of the recent large aircraft landing gear were given. The impact load for main welding outer cylinder in the process of the taking off and landing was calculated of 580MPa. Finite element model of the main welding outer cylinder was then established and the influence of the impact loading to the main welding outer cylinder was analyzed. The results showed that crack was most likely take place on the top of the outer cylinder, and then on the two welds. The crack expanded in an S shape. This study could provide an important basis for the safety of the aircraft landing gear inspection and service life prediction.

The Track-Controlling System for Mobile Greenhouse Robots

2013 ◽  
Vol 387 ◽  
pp. 258-261
Author(s):  
Lei Huang ◽  
Deng Xiang Yang ◽  
Qun Feng Zhu
Keyword(s):  
Control System ◽  
Motion Control ◽  
Control Algorithm ◽  
Control Parameters ◽  
Motion Control System ◽  
Stability Constraint ◽  
Controlling System ◽  
Photoelectric Encoder ◽  
The Impact

This paper targets on the study of the motion control system for greenhouse robots, and researches into the realization of the linear track control algorithm on robots motion control, demonstrating the feasibility and stability constraint of the algorithms. The author also analyzes the impact of different control parameters on the moving tracks through simulation, then applies the algorithm to the actual robot-controlling, and has designed an effective controlling system for mobile greenhouse robots based on gyroscopes and photoelectric encoder.

scholarly journals Selection Methodology of an Electric Actuator for Nose Landing Gear of a Light Weight Aircraft

2020 ◽  
Vol 10 (23) ◽  
pp. 8730
Author(s):  
Taimur Ali Shams ◽  
Syed Irtiza Ali Shah ◽  
Muhammad Ayaz Ahmad ◽  
Kashif Mehmood ◽  
Waseem Ahmad ◽  
...  
Keyword(s):  
Point Load ◽  
Landing Gear ◽  
Gear System ◽  
Electric Actuator ◽  
Equivalent Damping ◽  
Shock Absorbers ◽  
Electrical Actuator ◽  
Forcing Functions ◽  
Selection Methodology ◽  
The Impact

Landing gear system of an aircraft enables it to take off and land with safety and comfort. Because of the horizontal and vertical velocity of aircraft, upon landing, the complete aircraft undergoes different forcing functions in the form of the impact force that is absorbed by landing gears, shock absorbers, and actuators. In this research, a selection methodology has been proposed for an electrical actuator to be installed in the retraction mechanism of nose landing gear of an aircraft having 1600 kg gross takeoff weight. Nose landing gear and its associated components, like strut and shock absorbers, were modeled in CAD software. Analytical expressions were then developed in order to calculate the actuator stroke, translational velocity, force, and power for complete cycle of retraction, and some were subsequently compared with the computational results that were obtained using MSC ADAMS®. Air in the oleo-pneumatic shock absorber of nose landing gear was modeled as a nonlinear spring with equivalent spring constant, whereas hydraulic oil was modeled as a nonlinear damper with equivalent damping constant. The nose landing gear system was modeled as a mass-spring-damper system for which a solution for sinusoidal forcing functions is proposed. Finally, an electrical actuator has been selected, which can retract and extend nose landing gear, meeting all of the constraints of aircraft, like fuselage space, aircraft ground clearance, locking loads, power consumption, retraction and extension time, and dynamic response of aircraft. It was found that the selection of an electrical actuator is based upon the quantification of forces transmitted to electrical actuator during one point load at gross takeoff weight. The ability of retraction and extension time, as dictated by Federal Aviation Regulation, has also been given due consideration in the proposed methodology as significant criteria. The proposed system is now in the process of ground testing, followed by flight testing in the near future.

Simulation and Experimental Research of Hydraulic Actuator for Automatic Transmission

2013 ◽  
Vol 753-755 ◽  
pp. 1050-1053
Author(s):  
Yong Dao Song ◽  
Xiu Sheng Cheng ◽  
Qiang Gu ◽  
Hua Bin Hu
Keyword(s):  
Predictive Control ◽  
Experimental Research ◽  
Intelligent Control ◽  
Control Algorithm ◽  
Automatic Transmission ◽  
Hydraulic Actuator ◽  
Adaptive Ability ◽  
Actuator Control ◽  
Proportional Flow ◽  
Flow Valve

The accurate control of hydraulic actuator is critical for automatic transmission to launch or shift smoothly. The mathematical and simulation model of proportional flow valve based on Matlab/Simulink were established , and hydraulic actuator control arithmetic based on NNPC(Neuro Network Predictive Control) was introduced to realize accurate control of clutch displacement. The experiment was carried out and the rusults showed that the model of proportional flow valve was correct and hydraulic actuator intelligent control algorithm based on NNPC had good adaptive ability and high precision.

The Semi-Active Optimal Control Method of Aircraft Landing Gear

2012 ◽  
Vol 159 ◽  
pp. 390-394
Author(s):  
Jian Feng Wang ◽  
Xian Yu Zhang ◽  
Hong Wei Wang
Keyword(s):  
Optimal Control ◽  
Active Control ◽  
Passive Control ◽  
Ride Comfort ◽  
Control Method ◽  
Impact Load ◽  
Energy Requirement ◽  
Landing Gear ◽  
Practical Implementation ◽  
The Impact

When designing a landing gear damper, it is well-known that damper characteristics required for good handling are not the same as those required for good ride comfort. Semi-active control landing gear damper, as their name implies, fill the gap between purely passive damper and fully active control Langing gear-control systems and offer the reliability of passive systems, yet maintain the versatility and adaptability of fully active devices. During recent years there has been considerable interest towards theoretical study and practical practical implementation of this semi-active control landing gear damper for their low energy requirement and cost. For this reason, The basic theoretical for semi-active landing gear damper design and implementation has been briefly reviewed, mathematical model of semi-active control landing gear is established . A state feedback semi-active controller is designed. At last, the passive control landing gear model and semi -active control landing gear model are simulated. Simulation result shows that the vibration of passive control landing gear is vehement, and the system stable time is long.But in the simi-active control landing gear system the impact load and vibraton can be reduced, the aircraft can reach the stability state in a few seconds. Using linear quadratic optimal control effect is good.

Research on Single Neuron Adaptive PID Control

2012 ◽  
Vol 150 ◽  
pp. 174-177 ◽  
Author(s):  
Yan Hong Zhang ◽  
De An Zhao ◽  
Jian Sheng Zhang
Keyword(s):  
Neural Networks ◽  
Intelligent Control ◽  
Pid Control ◽  
Control Algorithm ◽  
Single Neuron ◽  
Control Parameters ◽  
Control Effect ◽  
The Common ◽  
Single Neuron Pid ◽  
Adaptive Pid Control

As a branch of the intelligent control, neural networks is applied in control more and more widely, the single neuron adaptive PID control algorithm is studied in this paper, and the program is written by MATLAB, the common object of single neuron adaptive PID is simulated, and the effect of single neuron adaptive PID control parameters on control effect is analyzed, experimental results show that the single neuron PID control has more obvious advantages than general PID control.

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