检索结果-南通市图书馆

Chinese Journal of Aeronautics 2022年第2期35卷 250-264页

作者： Wei FAN Bin XU changle xiang Yibo ZHANG Haiyang YANG School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401135China School of Automation Beijing Institute of TechnologyBeijing 100081China

This research concerns a novel attitude stabilization structure for a ducted-fan aerial robot to work against modeling error and strong external transient disturbance,and it focuses on two main control targets:modeling error compensation,and the improvement of disturbance resistance along the rolling channel.For the first research objective,we proposed an adaptive nominal controller with the reconfigurable control law design based on the estimation of the modeling error found in the closed-loop.Results of simulations and corresponding flight tests verified that the proposed adaptive control structure is robust against both constant and time-varying modeling error.For the other research objective,a SAC(Stability Augmentation Control)structure was devised based on the CMG(Control Moment Gyroscope)theory in order to provide extra moment which effectively withstands the transient disturbance beyond the CDG(Critical Disturbance Gain).Furthermore,we studied the corresponding controller for the SAC via the SMC(sliding mode control)theory,while the working mechanism and performance of the SAC were verified through a specially devised prototype.

关键词： Adaptive control Disturbance rejection Ducted-fan aircraft Modeling error Stability augmentation systems

在线全文

学校读者我要写书评

暂无评论

电驱动履带车辆转向稳定性控制研究

机械工程学报 2024年第8期60卷 233-244页

作者：侯旭朝马越项昌乐北京理工大学机械与车辆学院北京100081

履带车辆在高速转向时有侧滑和失控的风险。电驱动履带车辆能够达到高车速和较小的转向半径,主动轮转矩和转速控制灵活。基于转向动力学建模与特性分析,提出履带车辆转向稳定性控制方法。建立履带车辆转向动力学模型。模型考虑履带与地... 详细信息

履带车辆在高速转向时有侧滑和失控的风险。电驱动履带车辆能够达到高车速和较小的转向半径,主动轮转矩和转速控制灵活。基于转向动力学建模与特性分析,提出履带车辆转向稳定性控制方法。建立履带车辆转向动力学模型。模型考虑履带与地面间的摩擦与滑动,计算车辆转向动态过程中各履带板受到的作用力。通过数值计算得到车辆转向的相轨迹。分析系统的平衡点和稳定性,为转向控制器设计提供依据。对动力学模型进行简化,并依据简化模型设计履带车辆转向非线性自抗扰控制器(Active disturbance rejection control,ADRC),设计防侧滑控制策略。利用电驱动履带底盘在不同类型地面对提出的控制器进行验证。结果表明,与PID控制相比,提出的自抗扰转向控制方法将转向角速度跟踪的方均根误差降低7.43%,能够在较大转向角速度范围内稳定跟踪转向指令。提出的防侧滑控制方法显著提高了车辆高速转向的稳定性和平稳性。

关键词：履带车辆电驱动转向控制自抗扰控制稳定性

Robust adaptive fault-tolerant control of a tandem coaxial ducted fan aircraft with actuator saturation

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2018年第6期31卷 1298-1310页

作者： Xiaoliang WANG changle xiang Homayoun NAJJARAN Bin XU Vehicle Research Center School of Mechanical Engineering Beijing Institute of Technology Okanagan School of Engineering The University of British Columbia

This paper is concerned with the robust adaptive fault-tolerant control of a tandem coaxial ducted fan aircraft under system uncertainty, mismatched disturbance, and actuator saturation.For the proposed aircraft, comprehensive controllability analysis is performed to evaluate the controllability of each state as well as the margin to reject mismatched disturbance without any knowledge of the controller. Mismatched disturbance attenuation is ensured through a structured Hinfinity controller tuned by a non-smooth optimization algorithm. Embedded with the H-infinity controller, an adaptive control law is proposed in order to mitigate matched system uncertainty and actuator fault. Input saturation is also considered by the modified reference model. Numerical simulation of the novel ducted fan aircraft is provided to illustrate the effectiveness of the proposed method. The simulation results reveal that the proposed adaptive controller achieves better transient response and more robust performance than classic Model Reference Adaptive Control（MRAC） method, even with serious actuator saturation.

关键词： Comprehensive controllability Ducted fan aircraft Fault-tolerant Input saturation Robust adaptive control

Model-Based Double Closed-Loop Coordinated Control Strategy for the Electro-Mechanical Transmission System of Heavy Power-Split HEVs

在线全文

学校读者我要写书评

暂无评论

Automotive Innovation 2021年第1期4卷 44-55页

作者： Weida Wang Yuhang Zhang Xiaoxia Sun changle xiang Chao Yang School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China China North Vehicle Research Institute Beijing 100072China

The dual-mode electro-mechanical transmission(EMT)system is a crucial part of power-split hybrid electric vehicles(HEVs),especially for the heavy HEVs.To improve the precision of the system power distribution and the response speed of the electric power supply,a model-based double closed-loop coordinated control strategy is proposed.As the basis of the proposed control strategy,an EMT system model,particularly of an electrical system,is established first.The proposed control strategy includes the power distribution strategy,battery power closed-loop feedback control strategy,and motor coordinated control strategy.To verify the feasibility of the proposed control strategy,simulation and experiment are performed.The results indicate that the proposed control strategy can realize the expected power distribution by coordinating generators and motors and achieve rapid and stable electric power supply.

关键词： Hybrid electric vehicles Electro-mechanical transmission system Hybrid power-split Power coordinated control Multi-power distribution

Influence of Wall Effect on Comprehensive Controllability for Ducted Fan Aircraft

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Beijing Institute of Technology 2020年第4期29卷 581-591页

作者： Tianfu Ai changle xiang Bin Xu Wei Fan Yibo Zhang Vehicle Research Center School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

A novel coaxial ducted fan structure aircraft is proposed to enable the aircraft near vertical walls at high altitudes.The state space equation of the system can be obtained by correlation deduction and identification of the whole prototype model.Based on the duct test bench experiment and computational fluid dynamics(CFD)simulation analysis,the expressions between the different distances dWE from the rotor center of the prototype to the wall and the thrust,reaction torque,and tilting moment of the system under hovering conditions are obtained.The influence of the wall effect of the prototype is incorporated into the system model to analyze the relationship between distance dWE and the comprehensive controllability of the system.The results show that the system comprehensive controllability vector of other channels changes little with the decrease of the distance dWE,and only the controllability vector of the rolling channel increases significantly.At the same time,the tilting moment also increases significantly,which strengthens the tendency of the prototype to tilt towards the wall.

关键词： coaxial ducted fan aircraft hovering condition wall effect tilting moment comprehensive controllability analysis

A path planning algorithm for autonomous ﬂying vehicles in cross-countryenvironments with a novel TF-RRT^(*) method

在线全文

学校读者我要写书评

暂无评论

Green Energy and Intelligent Transportation 2022年第3期1卷 81-93页

作者： Tianqi Qie Weida Wang Chao Yang Ying Li Wenjie Liu changle xiang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing401120China

Autonomous flying vehicles(AFVs)are promising future vehicles,which have high obstacle avoidance ability.To plan a feasible path in a wide range of cross-country environments for the AFV,a triggered forward optimal rapidly-exploring random tree(TF-RRT^(*))method is proposed.Firstly,an improved sampling and tree growth mechanism is built.Sampling and tree growth are allowed only in the forward region close to the target point,which significantly improves the planning speed;Secondly,the driving modes(ground-driving mode or air-driving mode)of the AFV are added to the sampling process as a planned state for uniform planning the driving path and driving mode;Thirdly,according to the dynamics and energy consumption models of the AFV,comprehensive indicators with energy consumption and efficiency are established for path optimal procedures,so as to select driving mode and plan driving path reasonably according to the demand.The proposed method is verified by simulations with an actual cross-country environment.Results show that the computation time is decreased by 71.08%compared with Informed-RRT^(*)algorithm,and the path length of the proposed method decreased by 13.01%compared with RRT^(*)-Connect algorithm.

关键词： Autonomous flying vehicles(AFVs) Path planning Rapidly-exploring random tree(RRT) Mode switch

Theoretical and Experimental Investigations of Gyroplane Jump Takeoff Dynamics

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Harbin Institute of Technology(New Series) 2017年第3期24卷 57-66页

作者： Xingbang Yang changle xiang Bin Xu Wei Fan School of Mechanical Engineering Beijing Instituteof TechnologyBeijing 100081China State Key Laboratory of Vehicle Transmission Beijing Institute of TechnologyBeijing 100081’China

A nonlinear and time-varying gyroplane jump takeoff dynamics model considering the unsteady ground effect and the rapid blade-pitch increase(RBPI) is developed and validated against the experiment data.The precisions of the proposed model,an experienced Hollmann model and three other simplified models are compared by displaying the height and rpm time histories of those models and the experimental data.The mean square errors(MSE) of the height histories and maximum height errors(MHE) between those models are calculated and given out.The statistics provide a kind of evaluation method of importance of the unsteady ground effect,RBPI,and the induced velocity on jump takeoff performance in vertical phase.The impact of the unsteady ground effect and RBPI on the thrust and induced velocity of the experimental rotor of a small scale platform is analyzed.The study indicates that the proposed model agrees better with the experimental data than other models.It is useful for predicting the gyroplane jump takeoff performance for design.

关键词： jump takeoff rapid blade-pitch increase ground effect induced velocity MSE and MHE

NUMERICAL SIMULATION OF SOUND RADIATION ON GEARBOX'S HOUSING

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2008年第3期21卷 26-30页

作者： xiang changle WANG Wenping LIU Hui National Key Laboratory of Vehicle Transmission Beijing Institute of Technology Beijing 100081 China

The fluid-structure coupling finite element model and the boundary element model of a complex gearbox＇s housing are built based on the theory of fluid-structure coupling finite element method and boundary element method. At the same time, the exciting forces of the housing are analyzed and applied to the finite element models. Firstly, vibration of the housing is calculated by the fluid-structure coupling finite element model; secondly, the calculated result is verified by the experiment; finally, sound radiation of the housing is calculated by the boundary element. According to the calculated results, the housing adds some ribs not only to increase the strength, but also to reduce the sound radiation of the housing. At last, the sound radiation of the modified housing is calculated, which shows that the sound radiation of the modified housing with ribs is lower.

关键词： Sound radiation Finite element model Boundary element model Fluid-structure coupling

Economic MPC-based transient control for a dual-mode power-split HEV

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2017年第12期60卷 1917-1934页

作者： QI YunLong WANG WeiDa xiang changle ZHAO YuLong School of Mechanical Engineering Beijing Institute of Technology Beijing100081 China

The existing research into hybrid electric vehicle(HEV) control is mainly focussed on the optimisation of the power distribution between a conventional internal combustion engine(ICE) and an alternative power source(usually a battery pack), however,transient control, which is a key technique that affects both fuel economy and the drivability of the HEV, has not been fully addressed. Especially in dual-mode power-split HE Vs, due to the different dynamic characteristics of the actuators in the transmission, and its complicated speed-torque relationship, transient control also affects the precision of power distribution and the speed of response of the electric output power. To improve the transient control performance, the design of an economic model predictive control(EMPC)-based transient controller for a dual-mode power-split HEV is developed. By incorporating an experimental identification model of a diesel ICE in a control-oriented transmission model, a better coordination among the actuators involved in HEV transmission can be achieved. Moreover, an ICE efficiency index is also added to the objective function to improve ICE fuel efficiency during this transient process. Then, a fast MPC method is applied to reduce the on-line computation effort required of the proposed control algorithm. By the flexible application of the EMPC and an innovative ICE model which is suited to the control-oriented model in EMPC, the transient control performance was improved. The effectiveness,and the real-time performance,of the control algorithm are validated by way of MATLABTM/Simulink-based simulations,as well as test-bed experiments combined with the use of the RapidECU platform.

关键词： hybrid electric vehicle transient control fuel economy economic MPC fast MPC method

Analysis Method and Principle of Dual-mode Electro-mechanical Variable Transmission Program

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2012年第3期25卷 524-529页

作者： LI Hongcai YAN Qingdong xiang changle WANG Weida National Key Lab of Vehicular Transmission Beijing Institute of TechnologyBeijing 100081China

Automotive industry,as an important pillar of the national economy,has been rapidly developing in recent years.But proplems such as energy comsumption and environmental pollution are posed at the same time.Electro-mechanical variable transmission system is considered one of avilable workarounds.It is brought forward a kind of design methods of dual-mode electro-mechanical variable transmission system rotational speed characteristics and dual-mode drive diagrams.With the motor operating behavior of running in four quadrants and the speed characteristics of the simple internal and external meshing single planetary gear train,four kinds of dual-mode electro-mechanical transmission system scheme are designed.And the velocity,torque and power characteristics of one of the programs are analyzed.The magnitude of the electric split-flow power is an important factor which influences the system performance,so in the parameters matching design,it needs to reduce the power needs under the first mode of the motor.The motor,output rotational speed range and the position of the mode switching point have relationships with the characteristics design of the planetary gear set.The analysis method is to provide a reference for hybrid vehicles＇ design.As the involved rotational speed and torque relationships are the natural contact of every part of transmission system,a theory basis of system program and performance analysis is provided.

关键词： electro-mechanical variable transmission,dual-mode,rotational speed characteristics