Suspension mechanism simulation and optimization considering multiple disciplines

Hao Wang,Shaoping Wang,Mileta M. Tomovic 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.1

A new method in suspension mechanism design considering two coupled disciplines, dynamics and structure, has been proposed in this paper. One of the decomposition methods widely used in multidisciplinary design optimization (MDO)--collaborative optimization (CO) has been used in this work. CO is a bi-level optimization architecture that preserves the autonomy of individual disciplines. In subsystem level, these two disciplines share the same model from CAD models in preprocess stage. Data file and interface have been explained and implemented in detail. The result obtained has shown that it works well and the time cost is less than before.

Adaptive Fuzzy Robust Control of PMSM with Smooth Inverse Based Dead-zone Compensation

Xingjian Wang,Shaoping Wang 제어·로봇·시스템학회 2016 International Journal of Control, Automation, and Vol.14 No.2

It is a challenging work to design high precision/high performance motion controller for permanentmagnet synchronous motor (PMSM) due to some difficulties, such as varying operating conditions, parametricuncertainties and external disturbances. In order to improve tracking control performance of PMSM, this paperproposes an adaptive fuzzy robust control (AFRC) algorithm with smooth inverse based dead-zone compensation. Instead of nonsmooth dead-zone inverse which would cause the possible control signal chattering phenomenon, anew smooth dead-zone inverse is proposed for non-symmetric dead-zone compensation in PMSM system. AFRCcontroller is synthesized by combining backstepping technique and small gain theorem. Discontinuous projectionbasedparameter adaptive law is used to estimate unknown system parameters. The Takagi-Sugeno fuzzy logicsystems are employed to approximate the unstructured dynamics. Robust control law ensures the robustness ofclosed loop control system. The proposed AFRC algorithm with smooth inverse based dead-zone compensationis verified on a practical PMSM control system. The comparative experimental results indicate that the smoothinverse for non-symmetric dead-zone nonlinearity can effectively avoid the chattering phenomenon which wouldbe caused by nonsmooth dead-zone inverse, and the proposed control strategy can improve the PMSM outputtracking performance.

New approach of friction identification for electro-hydraulic servo system based on evolutionary algorithm and statistical logics with experiments

Xingjian Wang,Shaoping Wang 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.5

High-precision control of an Electro-hydraulic servo system (EHSS) should fully consider practical non-linearities, such as dynamic friction, in controller design. The LuGre model is widely used to describe non-linear friction, but parameter identification for this model remains a challenging task. This study proposes a novel identification approach for the LuGre model based on the Evolutionary algorithm (EA) and statistical logics. Identification experiments are also conducted for a practical EHSS. Static parameters are identified with constant velocity experiments. Moreover, the non-symmetry of friction in positive and negative rotary directions is fully considered. Dynamic parameters are identified with the pre-sliding process in the breakaway experiment. The EA is utilized to enhance the optimal estimation of friction parameters. Statistical logics are used to predict the deviations in the estimated results with high confidence interval. Furthermore, extensive simulation and experiment results validate the effectiveness of the proposed approach.

Adaptive Robust Torque Control of Electric Load Simulator with Strong Position Coupling Disturbance

Xingjian Wang,Shaoping Wang,Bin Yao 제어·로봇·시스템학회 2013 International Journal of Control, Automation, and Vol.11 No.2

Electric load simulator (ELS) is an important equipment to exert aerodynamic load to actuation system according to flight condition. The key issue of ELS is how to eliminate the influence of extra torque caused by actuation system, parametric uncertainties and uncertain nonlinearities. In order to overcome these difficulties, this paper proposes a powerful model-based adaptive robust torque control (ARTC) algorithm which transfers external disturbance elimination problem to a performance-oriented problem under uncertainties and nonlinearities. A discontinuous projection-based online parameter adaptation is employed to reduce the effect of various parameter uncertainties. Instead of discontinuous friction model, a continuous friction model based on smooth shape function is applied for friction compensation. The estimated velocity of actuator is utilized in ARTC controller for eliminating extra torque. The backstepping design via adaptive robust control Lyapunov function is employed to construct ARTC control law for ELS. Extensive comparative results indicate that the proposed ARTC controller is effective to achieve a guaranteed transient as well as final tracking accuracy in the presence of both parametric uncertainties and uncertain nonlinearities.

Photocatalytic Degradation of Rhodamine B via Fe-g-C3N4 Activated Sulfate Radical-Based Advanced Oxidation Processes and the Synergistic Mechanism

Zhan Xinyuan,She Zhixiang,Yue Zhengbo,Hu Fupeng,Wang Guangcheng,Wang Shaoping,Li Wei,Liu Bing,Wang Jin 한국화학공학회 2024 Korean Journal of Chemical Engineering Vol.41 No.1

Fe-doped g-C 3 N 4 has been proven to have the potential of visible light photocatalysis, but its catalytic activity of peroxymonosulfate (PMS) is neglected. Herein, the complex advanced oxidation processes of Fe-g-C 3 N 4 mediated PMS and visible light photocatalysis was developed, named as Vis/Fe-g-C 3 N 4 /PMS system, whose eff ects and synergistic mechanism for decomposing Rhodamine B (RhB) was evaluated. The coupling of sulfate radicals and photocatalysis for RhB degradation showed that the synergistic effi ciency ( η Syn ) and factor ( S c ) were 20.1% and 4.82, respectively, with a degradation effi ciency of 99.8%. Iron species dispersed on g-C 3 N 4 provided active sites for PMS activation to generate sulfate radicals, simultaneously reduced the forbidden band, and separated the photo-generated charges of g-C 3 N 4 . h + , SO 4 · ‾ and 1 O 2 were the main active species, and the increase of 1 O 2 was the cause of the synergistic eff ect. The possible degradation path of RhB by this coupling system was proposed. Our fi ndings prove that Vis/Fe-g-C 3 N 4 /PMS system has a great potential to decompose dye wastewater, and also to be an environmental remediation perspective.

Comparison of structural features and antioxidant activity of polysaccharides from natural and cultured Cordyceps sinensis

Junqiao Wang,Shaoping Nie,Lijiao Kan,Haihong Chen,Steve W. Cui,Aled O. Phillips,Glyn O. Phillips,Mingyong Xie 한국식품과학회 2017 Food Science and Biotechnology Vol.26 No.1

Four polysaccharides (named as P1, P2, and P3 from three natural Cordyceps sinensis and P4 from cultured C. sinensis) were obtained by hot-water extraction and ethanol precipitation and their structural characteristics as well as antioxidant potentials were compared. Results revealed that the backbone of P1, P2, and P3 comprised α-1,4-glucose, with a branching point mainly at position 6 and terminating at glucose. On the other hand, the structure of P4 was highly complex, mainly comprising glucose, galactose, and mannose, with 1,4-glucose and 1,4-galactose as the main chain. For in vitro antioxidant assays, all the four polysaccharides showed similar scavenging capacity against DPPH and hydroxyl radicals, whereas P1 had a relatively low ferric reducing ability, possibly related to a combination of factors such as the phenolic compounds and amino acids that conjugated in polysaccharides.

Application of Smart Technology in the Integrated Environmental Management of Urban Wetland Park

Xiaodan Zhao,Shaoping Wang 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.7

Wetland Park is one of the important ecological infrastructures. Besides providing the ecosystem service function and value, it is also an important place for leisure and entertainment. Efficient environmental management is an important measure to promote the sustainable development of the wetland park. By combining the smart technology with routine management method, the efficiency of the environmental management for the urban wetland park can be improved. The application of smart technology set the users' requirements as the basic goal, which is divided into four layers: perception layer, transport layer, support layer and application layer. The perception layer consists of sensor, camera, RFID, mobile terminal device and so on; the transport layer is composed of optical fiber, WIFI and 3G network; the support layer is composed of data management system, information open platform and service support system; and the application layer is composed of four modules including panoramic-view park, environmental maintenance, smart tourism and public participation. A wetland park located in Zhangzhou city, Fujian, China, was taken as a practice case.

A novel stress distribution analytical model of O-ring seals under different properties of materials

Di Wu,Shaoping Wang,Xingjian Wang 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.1

The elastomeric O-ring seals have been widely used as sealing elements in hydraulic systems. The sealing performance of O-ring seals is related to stress distribution. The stresses distribution depends on the squeeze rate and internal pressure, and would vary with properties of O-ring seals materials. Thus, in order to study the sealing performance of O-ring seals, it is necessary to describe the analytic relationship between stress distribution and properties of O-ring seals materials. For this purpose, a novel Stress distribution analytical model (SDAM) is proposed in this paper. The analytical model utilizes two stress complex functions to describe the stress distribution of O-ring seals. The proposed SDAM can express not only the analytical relationship between stress distribution and Young’s modulus, but also the one between stress distribution and Poisson’s ratio. Finally, compared results between finite element analysis and the SDAM validate that the proposed model can effectively reveal the stress distribution under different properties for O-ring materials.

Modeling, Analysis and Testing of Load Distribution for Planetary Gear Trains with 3D Carrier Pinhole Position Errors

Huimin Dong,Chu Zhang,Shaoping Bai,Delun Wang 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.8

A discrete model to study the load distribution behavior of helical planetary gear trains (PGTs) is developed, in which 3D planet position errors, induced by carrier pinhole position errors and tooth modifications, are duly considered. The model adopts a discrete approach with which the planetary gear train is discretized into a series of slice-units in order to ease the problem of gear meshing in 3D cases. In the modelling, compatibility conditions and discrete equilibrium are developed for the coupling among 3D planet position errors, tooth modifications, instantaneous meshing situations, elastic deformations and rigid body spatial motions. Upon the discrete model, a method for analysis of the load distribution is further developed. The influence of 3D planet position errors and tooth modifications on the load distribution was simulated for a helical PGT having three and four planets. Tests on the actual wind turbine PGTs were conducted with results agreed with the simulations obtained, which validate the proposed method.

A Novel Fixed Twin-Rotor Unmanned Aerial Vehicle with Variable Angle Louver Rudder

Yixin Zhang,Jianfeng Zhou,Shaoping Wang,Mengqi Yang,Shaoshi Li 제어로봇시스템학회 2021 제어로봇시스템학회 국제학술대회 논문집 Vol.2021 No.10

A novel fixed twin-rotor unmanned aerial vehicle (UAV) based on the variable angle louver rudder (VALR) is developed in this work. In view of the mechanical characteristics under the action of the louver rudder, specific kinematics and dynamics models are derived. The aerodynamic characteristics of the UAV are studied through computational fluid dynamics simulation, and a ground measurement system is designed to analyze the aerodynamic characteristics of the prototype. An attitude control model is proposed, and maneuvers such as take-off, landing, hovering, and braking are realized through flight experiments, which verify the feasibility of the prototype design. This research shows that the new layout with the VALR system, combined with the advantages of rudder control and vector control, can reduce the structural complexity and deadweight of the UAV while ensuring flight stability and improving maneuverability. Moreover, the novel UAV has higher energy efficiency and economy.