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Perturbation Analysis and control of Mach Number 2.4-Meter Transonic Wind Tunnel

JOURNAL OF AIRCRAFT 2020年第6期57卷 1148-1155页

作者： Yu, Wenshan Du, Ning Rao, Zhengzhou Wei, Zhi Yuan, Ping Natl Univ Def Technol Coll Intelligent Syst Changsha 410003 Hunan Peoples R China China Aerodynam Res & Dev Ctr High Speed Aerodynam Inst Mianyang 621000 Sichuan Peoples R China Northeastern Univ Inst Automatizat Shenyang 110000 Liaoning Peoples R China

Because of the large domestic civil aircraft projects started in China a decade ago, there is a greater need to control the accuracy of the Mach number in aerodynamic tests, especially near the designed cruise point of large commercial aircraft. Nowadays the control accuracy of China Aerodynamics Research and Development Center 2.4-meter transonic wind tunnel Mach number is in the range of +/- 0.002 to +/- 0.003 when M <= 0.9, which is far from the measurement accuracy of drag coefficient required for testing advanced aircraft. This value should result in a better-than-one drag count. As a consequence, it is imperative to improve the control accuracy of Mach number urgently. The nonlinearity, large time delays, and strong coupling of wind tunnel flowfield control, along with the variation of the model angle of attack, could cause the Mach number to deviate from the expected value. To solve these problems, a model predictive control method based on dynamic matrix control algorithm is proposed. This method builds a prediction model based on step response test. The accuracy of Mach number predictive control can be efficiently improved by performance optimization in the form of vector norms, rolling optimization, and feed-forward compensation. This control strategy has been successfully tested in the wind tunnel, and the control accuracy of Mach number has been remarkably enhanced, to the point where it can be controlled to within +/- 0.0015. This value satisfies the requirements of aerodynamic aircraft testing.

关键词： Transonic Wind Tunnel Aerodynamic Characteristics Angle of Attack predictive control method China Aerodynamics Research and Development Center Commercial Aircraft Civil Aircraft control Algorithm Perturbation Analysis Static Pressure

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Multiple Target Tracking Via Dynamic Point Clustering on a UAV Platform

Multiple Target Tracking Via Dynamic Point Clustering on a U...

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AIAA Science and Technology (SciTech) Forum and Exposition

作者： Holsinger, Seth Sharma, Rajnikant Univ Cincinnati Aerosp Engn Cincinnati OH 45221 USA

ISBN: (数字)9781624105784

ISBN: (纸本)9781624105784

This research focuses on solving the problem of tracking multiple ground targets from a single or multiple UAV's utilizing a dynamic clustering algorithm. The location of each of the targets can be ascertained by using a geolocation method with a camera as the primary sensor. Each UAVis assumed to have only one camera that is mounted on a two axis gimbal. The targets will not be able to transmit any of their location data to the UAVs. An extended Kalman filter is used to estimate the location and velocity of the targets with the afore mentioned geolocation used as the update step. The algorithm uses the estimated target locations and the distance from the UAV to different point locations to find the maximum number of targets that the camera can view at once. These clusters of points are then subject to a cost function where the goal is the minimize the overall uncertainty of all of the system. While also staying below a maximum allowable uncertainty for individual targets. The approach taken by this method is scalable with the number of UAVs and ground targets that it can track to allow for it to be used in a wide variety of circumstances.

关键词： Extended Kalman Filter Sensor Fusion Geolocation Monte Carlo Simulation Track Algorithm MATLAB Earth predictive control method Gaussian White Noise Autonomous Systems

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Uncertainty Aware Geo-localization of Multi-Targets with Multi-UAV using Neural Network and Extended Kalman Filter

Uncertainty Aware Geo-localization of Multi-Targets with Mul...

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AIAA Science and Technology (SciTech) Forum and Exposition

作者： Khanapuri, Eshaan Sharma, Rajnikant Univ Cincinnati Dept Aerosp Engn & Engn Mech Cincinnati OH 45221 USA

ISBN: (数字)9781624105784

ISBN: (纸本)9781624105784

In this paper we propose a Neural Network based approach to improve the accuracy in the estimated positions of multiple targets and minimize their uncertainty using multiple small fixed wing Unmanned Aerial Vehicle (UAV). The UAVs are equipped with a gimbal camera to track the targets. To Geo-localize the targets they should remain inside the Field of View (FOV) of the camera. Extended Kalman Filter (EKF) is used to estimate target's positions. As long as the targets are in the FOV the error in the estimated positions of the targets will be low. The challenge here is to predict the azimuth and elevation angles of gimbal cameras such that multiple targets remain inside the FOV. This is achieved by training a Neural Network with backpropogation to predict the required azimuth and elevation angles for each UAV. In certain cases when multiple targets cannot be kept in the FOV of the camera, neural network predicts gimbal angles for each UAV such that they can observe atleast one target each. Using simulation results we can see the effectiveness of the proposed approach and also show that the estimated position and uncertainty of targets are better with Neural Network compared to Model predictive control method.

关键词： Neural Network methods Extended Kalman Filter Unmanned Aerial Vehicle predictive control method Computer Vision Geolocation Robust Algorithm Pressure Sensors Yaw

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Communication-Aware Trajectory Planning for Unmanned Aerial Vehicles in Urban Environments

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JOURNAL OF GUIDANCE control AND DYNAMICS 2018年第10期41卷 2269-2280页

作者： Oh, Hyondong Shin, Hyo-Sang Kim, Seungkeun Chen, Wen-Hua Ulsan Natl Inst Sci & Technol Sch Mech Aerosp & Nucl Engn Ulsan 44919 South Korea Cranfield Univ Inst Aerosp Sci Cranfield MK43 0AL Beds England Chungnam Natl Univ Dept Aerosp Engn 99 Daehak Ro Daejeon 305764 South Korea Loughborough Univ Dept Aeronaut & Automot Engn Loughborough LE11 3TU Leics England

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Concurrent Rendezvous control of Underactuated Space Manipulators

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JOURNAL OF GUIDANCE control AND DYNAMICS 2019年第11期42卷 2501-2510页

作者： Zong, Lijun Emami, M. Reza Muralidharan, Vijay Northwestern Polytech Univ Natl Key Lab Aerosp Flight Dynam Xian 710072 Shaanxi Peoples R China Univ Toronto Inst Aerosp Studies Toronto ON M3H 5T6 Canada Lulea Univ Technol Space Technol Div Onboard Space Syst S-98128 Kiruna Sweden

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Fast and Near-Optimal Guidance for Docking to Uncontrolled Spacecraft

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JOURNAL OF GUIDANCE control AND DYNAMICS 2017年第12期40卷 3138-3154页

作者： Ventura, Jacopo Ciarcia, Marco Romano, Marcello Walter, Ulrich Tech Univ Munich Inst Astronaut Boltzmannstr 15 D-85748 Garching Germany Naval Postgrad Sch Dept Mech & Aerosp Engn 700 Dyer RdWatkins Hall Monterey CA 93940 USA Tech Univ Munich Inst Astronaut Boltzmannstr 15 D-85748 Garching Germany

This paper proposes a guidance scheme for autonomous docking between a controlled spacecraft and an uncontrolled tumbling target in circular orbit. The onboard trajectory planning consists of a direct optimization method based on the inversion of the system dynamics. The trajectory components of the controlled spacecraft are imposed by using polynomial functions. Some of the polynomial coefficients are constrained to satisfy path constraints, whereas the remaining coefficients are varied parameters to be optimized. The optimal control problem is converted into a nonlinear programming problem by inverting the system dynamics. The proposed guidance scheme, based on the closed-loop implementation of this optimization problem, is applied to several scenarios. The resulting trajectories closely match the solutions of the correspondent optimal control problems. The guidance scheme is shown to perform precise maneuvers in most maneuvering situations, even in the presence of orbital perturbations. The sensitivity analysis to system uncertainties shows that the guidance is sensitive to noise on the target angular velocity, being the critical disturbance for this type of maneuvers.

关键词： Spacecrafts Trajectory Optimization predictive control method Nonlinear Programming Sensitivity Analysis Autonomous Docking Target Spacecraft Guidance System Robust Guidance Algorithm Standard Gravitational Parameter

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Introducing Computational Guidance and control

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JOURNAL OF GUIDANCE control AND DYNAMICS 2017年第2期40卷 193-193页

作者： Lu, Ping

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Experimental Characterization of Inverse Dynamics Guidance in Docking with a Rotating Target

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JOURNAL OF GUIDANCE control AND DYNAMICS 2016年第6期39卷 1173-1187页

作者： Wilde, Markus Ciarcia, Marco Grompone, Alessio Romano, Marcello Naval Postgrad Sch Monterey CA 93940 USA Florida Inst Technol Dept Mech & Aerosp Engn Melbourne FL 32904 USA Naval Postgrad Sch Mech & Aerosp Engn Dept Monterey CA 93940 USA

The performance of an inverse dynamics guidance and control strategy is experimentally evaluated for the planar maneuver of a "chaser" spacecraft docking with a rotating "target." The experiments were conducted on an airbearing proximity maneuver testbed. The chaser spacecraft simulator consists of a three-degree-of-freedom autonomous vehicle floating via air pads on a granite table and actuated by thrusters. The target consists of a docking interface mounted on a rotational stage with the rotation axis perpendicular to the plane of motion. Given a preassigned trajectory, the guidance and control strategy computes the required maneuver control forces and torque via an inverse dynamics operation. The recorded data of 150 experimental test runs were analyzed using two-way analysis of variance and post hoc Tukey tests. The metrics were maneuver success, vehicle mass change, maneuver duration, thruster duty cycle, and maneuver work. The results showed that the guidance and control algorithm provided robust performance over a range of target rotation rates from 1 to 4 deg /s. The effects of the rate estimation errors are measurable but not dominant.

关键词： Analysis of Variance control Algorithm Three Degrees of Freedom Spacecraft Docking Flight Phases Propellant predictive control method Rendezvous and Docking Algorithms Statistical Analysis Numerical Simulation

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Bridge Arms Current Tracking predictive control of Modular Multilevel Converter for HVDC system 7

Bridge Arms Current Tracking Predictive Control of Modular M...

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7th International Conference on Intelligent Human-Machine Systems and Cybernetics (IHMSC)

作者： Liu, Xiangjie Xu, Huimin Zhang, Xuedong North China Elect Power Univ State Key Lab Alternate Elect Power Syst Renewabl Beijing Peoples R China China Elect Power Univ Sch Energy & Power Engn North China Elect Power Univ Baoding Beijing Peoples R China

ISBN: (纸本)9781479986460

in order to suppress circulation current, a predictive control method based on error model of system is proposed. Firstly, we set up the discrete model of the controlled system by Eulor's formula, and then derive the tracking error discrete model, finally, the desired AC current is tracked completely by the actual current. the merits of the error model predictive control is that the error model eliminates the repeat errors in the time index and the predictive control and Kalman filter remove the random error. the calculated amount is too heavy to be implemented by the computer in the model predictive control for modular multilevel converters when the numbers of the sub-modular is high, a explicit optimal grouping method is bring forward according to the mean inequality, and reduce the computer burden. the simulation result show the proposed control strategy is of feasibility and superiority

关键词： predictive control method modular multilevel converters error model desired bridge arms current optimal grouping method

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A Simple Current control Strategy for Four-leg Direct Matrix Converter

A Simple Current Control Strategy for Four-leg Direct Matrix...

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Chinese Automation Congress (CAC)

作者： Han Hua Li Zhejun Mao Yongmei Wang Hui Dan Hanbing Wen Meng Cent South Univ Sch Informat Sci & Engn Changsha Hunan Peoples R China

ISBN: (纸本)9781467371896

A four-leg Matrix converter is built based on conventional Matrix converter. It is required to provide a path for the zero-sequence load current when the added midline bridge connects the neutral point of load. In this paper, a model predictive control method for a four-leg matrix converter under unbalanced load condition is described. The predictive control method is based on the optimal selection among the valid switching states of the converter by evaluating a cost function. Compared with the conventional method, the predictive control method is simple to implement without coordination transformation and duty ratio calculation. To support the theoretical analysis, the feasibility and reliability of the proposed method are verified by simulation results.

关键词： Unbalanced load direct matrix converter predictive control method

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