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swing Suppression and Accurate Positioning Control for Underactuated Offshore Crane Systems Suffering From Disturbances

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IEEE/CAA Journal of Automatica Sinica 2020年第3期7卷 892-900页

作者： Tong Yang Ning Sun He Chen Yongchun Fang Institute of Robotics and Automatic Information Systems(IRAIS) College of Artificial IntelligenceTianjin 300350China Tianjin Key Laboratory of Intelligent Robotics(tjKLIR) Nankai UniversityTianjin 300350China IEEE School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China

Offshore cranes are widely applied to transfer largescale cargoes and it is challenging to develop effective control for them with sea wave disturbances. However, most existing controllers can only yield ultimate uniform boundedness or asymptotical stability results for the system's equilibrium point, and the state variables' convergence time cannot be theoretically guaranteed. To address these problems, a nonlinear sliding mode-based controller is suggested to accurately drive the boom/rope to their desired positions. Simultaneously, payload swing can be eliminated rapidly with sea waves. As we know, this paper firstly presents a controller by introducing error-related bounded functions into a sliding surface, which can realize boom/rope positioning within a finite time, and both controller design and analysis based on the nonlinear dynamics are implemented without any linearization manipulations. Moreover, the stability analysis is theoretically ensured with the Lyapunov method. Finally, we employ some experiments to validate the effectiveness of the proposed controller.

关键词： Boom/rope positioning offshore cranes swing elimination underactuated systems

A Direct swing Constraint-based Trajectory Planning Method for Underactuated Overhead Cranes

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自动化学报 2014年第11期40卷 2414-2419页

作者： WANG Peng-Cheng FANG Yong-Chun JIANG Zi-Ya Institute of Robotics and Automatic Information System (IRAIS) Nankai University Tianjin 300071 China Tianjin Key Laboratory of Intelligent Robotics Nankai University Tianjin 300071 China State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016. China

This paper proposes a novel swing constraint-based trajectory planning method for nonlinear overhead crane systems. To enhance the efficiency and security of the transportation process, some desired trajectories are designed to achieve the following merits: 1) leading the trolley to reach the destination sufficiently fast; 2) keeping the payload swing in an acceptable domain; linebreak 3) eliminating the residue swing when the trolley stops at the desired position. Specifically, the trajectories are divided into three stages. For each stage, the desired curve of the swing angle is directly constructed in accordance with anti-swing and zero-residual swing requirements, based on which the trolley trajectory is then obtained by analyzing the nonlinear kinematics of the crane system. An optimization mechanism is introduced to make intelligent compromises among the indices of transportation time, maximal swing angle, and so on. Both simulation and experimental results are provided to demonstrate the performance of the proposed direct swing constraint-based trajectory planning method.

关键词：桥式起重机基于约束 swing 欠驱动规划法非线性运动学载荷摆动轨迹规划

Motion Control of Capsule-like Underwater Robot Utilizing the swing Properties of Ionic Polymer Metal Composite Actuators

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Journal of Bionic Engineering 2020年第2期17卷 281-289页

作者： Hongkai Li Min Fan Yinghao Yue Guoliang Hu Qingsong He Min Yu Key Laboratory of Bionic Functional Materials of Jiangsu Province Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Science and Technology on Electro-optic Control Laboratory Luoyang 471000China

Ionic Polymer Metal Composite(IPMC)is a novel electrically actuated intelligent material with the advantages of big bending displacement,low driving voltage,flexible and so on.It has been recognized as one of the most attractive actuators with prospective applications for underwater robots and bionic organs.In this work,a capsule-like robot was introduced with the pectoral and caudal fins made of IPMC.By analyzing the properties of displacement response to square waves with different frequencies and low level voltages,it was found that performance of IPMC are frequency sensitive.Besides,when the absolute value of low level voltage decreases,IPMC could swing on one side with the decrease in amplitudes,whereas the amplitude at high level voltage fluctuates within small ranges at low frequencies.IPMC tip can approximately maintain when the frequency of driving signal around 30 Hz.Such properties were employed to control the locomotion of robot combining the motions of pectoral and caudal fin.Thus,the locomotions of swimming forward,turning and positioning were realized.

关键词： underwater robot open-loop control IPMC swing property displacement response

Determination of Newtonian gravitational constant G with swing time method

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Science China Mathematics 1998年第12期41卷 1289-1295页

作者：罗俊胡忠坤傅湘辉唐孟希范淑华 Center for Gravitational Experiment Huazhong University of Science and Technology Wuhan China Department of Physics Zhongshan University Guangzhou China

The Newtonian gravitational constant G is determined by means of the swing time method at the Cave Laboratory of Center for Gravitational Experiment of Huazhong University of Science and Technology. The result value of G is (6.669 0±0.001 6)×10 -11 m 3·kg -1 ·s -2 , which is consistent with the CODATA value of G obtained by Cohen and Taylor in 3σ .

关键词： gravitational constant torsion balance swing time method.

Pressure swing adsorption modeling of acetone and toluene on activated carbon

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Journal of Central South University 2013年第10期20卷 2781-2790页

作者：唐琳李立清邢俊东刘峥姚小龙 School of Energy Science and Engineering Central South University

A five steps pressure swing adsorption process was designed for acetone and toluene mixtures separation and recovery. Dynamic distributions of gas phase content and temperature were investigated. Based on the theory of Soret and Dufour, a non-isothermal mathematical model was developed to simulate the PSA process. Effects of heat and mass transfer coefficients were studied. The coupled Soret and Dufour effects were also evaluated. It is found that the heat transfer coefficient has little effect on mass transfer in adsorption stage. However, it has some impacts in desorption stage. The maximum value of C/C0 increases by about 25% as heat transfer coefficient decreases. The temperature variation is less than 0.05 K with the change of mass transfer coefficient, so that the effect of mass transfer coefficient on heat transfer can be ignored. It is also concluded that the Soret and Dufour coupled effects are not obvious in pressure swing adsorption compared with fixed-bed adsorption.

关键词： pressure swing adsorption heat transfer mass transfer Soret and Dufour effects activated carbon

Pressure swing Distillation for Separation of Ethyl Acetate and Ethanol in Sub-plateau Region

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China Petroleum Processing & Petrochemical Technology 2020年第1期22卷 104-110页

作者： Wang Keliang Li Jing Lian Minglei Li Zhi Du Tingzhao College of Chemistry and Materials Engineering Liupanshui Normal UniversityLiupanshui 553004 North China Company China Petroleum Engineering Co.Ltd.Renqiu 062552

The pressure swing distillation(PSD)process for separation of ethyl acetate and ethanol mixture in subplateau region was simulated.The pressure of low-pressure column was set at 0.086 MPa,which is in accordance with the atmospheric pressure in the Yunnan-Guizhou region,while the pressure of high-pressure column was determined as 0.304 MPa.Various design parameters,including the plate number,the reflux ratio,and the feeding positions,were optimized,while taking into consideration the total annual cost(TAC).Furthermore,based on the general PSD,the partially heatintegrated pressure swing distillation(PHIPSD)process and the fully heat-integrated pressure swing distillation(FHIPSD)process were also studied.The processes with heat integration showed lower capital cost and lower energy cost,and TACs of the PHIPSD and FHIPSD decreased to 377.21×103$/a and 371.66×103$/a,respectively.Compared with the non-heat integrated process,TACs of the PHIPSD and FHIPSD could be reduced by 27.82%and 28.89%,respectively.The results showed that the FHIPSD process could effectively separate the ethyl acetate-ethanol mixture,and it was more economical and reasonable.This work can provide some technical references for the separation of such azeotropes in the sub-plateau region.

关键词： pressure swing distillation ethyl acetate ethanol azeotrope heat-integrated

Industrial E-commerce Develops in Full swing

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China's Foreign Trade 2023年第1期 56-57页

作者： Jenny Hu 不详

In 2022,the role of digital economy as a stabilizer and accelerator of the national economy was more prominent.Industry digitalization,which is driven by China’ s intelligent manufacturing,has become the main engine of China’ s digital economy development.As the core component of industrial digitalization,industrial e-commerce also developed in full swing.In the past three years,the COVID-19 pandemic has brought plenty of pressure to China’s industrial economy.

关键词： plenty commerce swing

Trajectory tracking control of the bionic joint of the musculoskeletal leg mechanism

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High Technology Letters 2017年第2期23卷 117-124页

作者：雷静桃 Zhu Jianmin Wu Jiandong School of Mechatronic Engineering and Automation Shanghai University College of Mechanical Engineering University of Shanghai for Science and Technology

Pneumatic artificial muscles(PAMs) have properties similar to biological muscles,which are widely used in robotics as actuators.It is difficult to achieve high-precision position control for robotics system driven by PAMs.A 3-DOF musculoskeletal bionic leg mechanism is presented,which is driven by PAMs for quadruped robots.PAM is used to simulate the compliance of biological muscle.The kinematics of the leg swing is derived,and the foot desired trajectory is planned as the sinusoidal functions.The swing experiments of the musculoskeletal leg mechanism are conducted to analyse the extension and flexion of joints.A proportional integral derivative(PID) algorithm is presented for controlling the flexion/extension of the joint.The trajectory tracking results of joints and the PAM gas pressure are obtained.Experimental results show that the developed leg mechanism exhibits good biological properties.

关键词： musculoskeletal leg mechanism swing bionic joint trajectory tracking proportional integral derivative(PID) control

Stitching swing arm profilometer test for large aperture aspherics

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Chinese Optics Letters 2019年第11期17卷 75-79页

作者：熊玲戚二辉罗霄张峰薛栋林张学军 Key Laboratory of Optical System Advanced Manufacturing Technology Changchun Institute of OpticsFine Mechanics and Physics Chinese Academy of Sciences

We implemented a stitching swing arm profilometer(SSAP) test for the inner and outer regions of a large aspheric surface with a short arm. The SSAP was more capable of improving sampling density of surface and was less sensitive to system error, like vibration noise and air-table noise. Firstly, a calculation model was built to evaluate the sampling density of the SSAP test. Then, sensitivity to system noise was tested when different lengths of arm were used. At the end, an experiment on a 3 m diameter aspheric mirror was implemented, where test efficiency was promoted, and high sampling density was achieved.

关键词： system mirror swing