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Motion/Posture Modeling and Simulation Verification of Physically Handicapped in Manufacturing System Design 被引量:3
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作者 FU Yan LI Shiqi CHEN Gwen-guo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期225-231,共7页
Non-obstacle design is critical to tailor physically handicapped workers in manufacturing system. Simultaneous consideration of variability in physically disabled users, machines and environment of the manufacturing s... Non-obstacle design is critical to tailor physically handicapped workers in manufacturing system. Simultaneous consideration of variability in physically disabled users, machines and environment of the manufacturing system is extremely complex and generally requires modeling of physically handicapped interaction with the system. Most current modeling either concentrates on the task results or functional disability. The integration of physical constraints with task constraints is far more complex because of functional disability and its extended influence on adjacent body parts. A framework is proposed to integrate the two constraints and thus model the specific behavior of the physical handicapped in virtual environment generated by product specifications. Within the framework a simplified model of physical disabled body is constructed, and body motion is generated based on 3 levels of constraints(effecter constraints, kinematics constraints and physical constraints). The kinematics and dynamic calculations are made and optimized based on the weighting manipulated by the kinematics constraints and dynamic constraints. With object transferring task as example, the model is validated in Jack 6.0. Modelled task motion elements except for squatting and overreaching well matched with captured motion elements. The proposed modeling method can model the complex behavior of the physically handicapped by integrating both task and physical disability constraints. 展开更多
关键词 physical handicapped motion/posture modeling manufacturing system design
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Nursing model of midwifery and postural and psychological interventions:Impact on maternal and fetal outcomes and negative emotions of primiparas 被引量:1
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作者 Ping Gao Cai-Qiong Guo +1 位作者 Ma-Yu Chen Hui-Ping Zhuang 《World Journal of Psychiatry》 SCIE 2023年第8期543-550,共8页
BACKGROUND Primiparas are usually at high risk of experiencing perinatal depression,which may cause prolonged labor,increased blood loss,and intensified pain,affecting maternal and fetal outcomes.Therefore,interventio... BACKGROUND Primiparas are usually at high risk of experiencing perinatal depression,which may cause prolonged labor,increased blood loss,and intensified pain,affecting maternal and fetal outcomes.Therefore,interventions are necessary to improve maternal and fetal outcomes and alleviate primiparas’negative emotions(NEs).AIM To discusses the impact of nursing responsibility in midwifery and postural and psychological interventions on maternal and fetal outcomes as well as primiparas’NEs.METHODS As participants,115 primiparas admitted to Quanzhou Maternity and Child Healthcare Hospital between May 2020 and May 2022 were selected.Among them,56 primiparas(control group,Con)were subjected to conventional midwifery and routine nursing.The remaining 59(research group,Res)were subjected to the nursing model of midwifery and postural and psychological interventions.Both groups were comparatively analyzed from the perspectives of delivery mode(cesarean,natural,or forceps-assisted),maternal and fetal outcomes(uterine inertia,postpartum hemorrhage,placental abruption,neonatal pulmonary injury,and neonatal asphyxia),NEs(Hamilton Anxiety/Depressionrating Scale,HAMA/HAMD),labor duration,and nursing satisfaction.RESULTS The Res exhibited a markedly higher natural delivery rate and nursing satisfaction than the Con.Additionally,the Res indicated a lower incidence of adverse events(e.g.,uterine inertia,postpartum hemorrhage,placental abruption,neonatal lung injury,and neonatal asphyxia)and shortened duration of various stages of labor.It also showed statistically lower post-interventional HAMA and HAMD scores than the Con and pre-interventional values.CONCLUSION The nursing model of midwifery and postural and psychological interventions increase the natural delivery rate and reduce the duration of each labor stage.These are also conducive to improving maternal and fetal outcomes and mitigating primiparas’NEs and thus deserve popularity in clinical practice. 展开更多
关键词 Nursing model of midwifery postural intervention PRIMIPARA Maternal and fetal outcomes Negative emotions
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A Realistic 3D Non-Stationary Channel Model for UAV-to-Vehicle Communications Incorporating Fuselage Posture
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作者 Boyu Hua Tongtong Zhou +3 位作者 Qiuming Zhu Kai Mao Junwei Bao Weizhi Zhong 《China Communications》 SCIE CSCD 2023年第6期277-290,共14页
Considering the unmanned aerial vehicle(UAV) three-dimensional(3D) posture, a novel 3D non-stationary geometry-based stochastic model(GBSM) is proposed for multiple-input multipleoutput(MIMO) UAV-to-vehicle(U2V) chann... Considering the unmanned aerial vehicle(UAV) three-dimensional(3D) posture, a novel 3D non-stationary geometry-based stochastic model(GBSM) is proposed for multiple-input multipleoutput(MIMO) UAV-to-vehicle(U2V) channels. It consists of a line-of-sight(Lo S) and non-line-of-sight(NLo S) components. The factor of fuselage posture is considered by introducing a time-variant 3D posture matrix. Some important statistical properties, i.e.the temporal autocorrelation function(ACF) and spatial cross correlation function(CCF), are derived and investigated. Simulation results show that the fuselage posture has significant impact on the U2V channel characteristic and aggravate the non-stationarity. The agreements between analytical, simulated, and measured results verify the correctness of proposed model and derivations. Moreover, it is demonstrated that the proposed model is also compatible to the existing GBSM without considering fuselage posture. 展开更多
关键词 channel model unmanned aerial vehicle NON-STATIONARY fuselage posture
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Human Body Modeling and Posture Simulating Based on 3D Surface Scan Data
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作者 马永有 张辉 +1 位作者 任少云 蒋寿伟 《Journal of Donghua University(English Edition)》 EI CAS 2003年第3期51-56,共6页
This paper presents a new approach for modeling the human body by considering the motion state and the shape of whole body. The body model consists of a skeleton kinematic model and a surface model. The former is used... This paper presents a new approach for modeling the human body by considering the motion state and the shape of whole body. The body model consists of a skeleton kinematic model and a surface model. The former is used to determine the posture of the body,and the latter is used to generate the body shape according to the given posture. The body surface is reconstructed with multi-segment B-spline surfaces based on the 3D scan data from a real human body.Using only a few joints parameters and the original surface scan data, the various body postures and the shape can be generated easily. The model has a strong potential of being used for ergonomic design,garment design, virtual reality environment, as well as creating human animation, etc. 展开更多
关键词 Human body Geometric madding Surface reconstruction Kinematic model posture simulating
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Error Modeling and Sensitivity Analysis of a Parallel Robot with SCARA(Selective Compliance Assembly Robot Arm) Motions 被引量:18
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作者 CHEN Yuzhen XIE Fugui +1 位作者 LIU Xinjun ZHOU Yanhua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第4期693-702,共10页
Parallel robots with SCARA(selective compliance assembly robot arm) motions are utilized widely in the field of high speed pick-and-place manipulation. Error modeling for these robots generally simplifies the parall... Parallel robots with SCARA(selective compliance assembly robot arm) motions are utilized widely in the field of high speed pick-and-place manipulation. Error modeling for these robots generally simplifies the parallelogram structures included by the robots as a link. As the established error model fails to reflect the error feature of the parallelogram structures, the effect of accuracy design and kinematic calibration based on the error model come to be undermined. An error modeling methodology is proposed to establish an error model of parallel robots with parallelogram structures. The error model can embody the geometric errors of all joints, including the joints of parallelogram structures. Thus it can contain more exhaustively the factors that reduce the accuracy of the robot. Based on the error model and some sensitivity indices defined in the sense of statistics, sensitivity analysis is carried out. Accordingly, some atlases are depicted to express each geometric error’s influence on the moving platform’s pose errors. From these atlases, the geometric errors that have greater impact on the accuracy of the moving platform are identified, and some sensitive areas where the pose errors of the moving platform are extremely sensitive to the geometric errors are also figured out. By taking into account the error factors which are generally neglected in all existing modeling methods, the proposed modeling method can thoroughly disclose the process of error transmission and enhance the efficacy of accuracy design and calibration. 展开更多
关键词 parallel robot selective compliance assembly robot arm(SCARA) motions error modeling sensitivity analysis parallelogram structure
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Physics-based Modeling and Simulation for Motional Cable Harness Design 被引量:6
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作者 LIU Jianhua ZHAO Tao +1 位作者 NING Ruxin LIU Jiashun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第5期1075-1082,共8页
The design work of motional cable in products is vital due to the difficulty in estimating the potential issues in current researches.In this paper,a physics-based modeling and simulation method for the motional cable... The design work of motional cable in products is vital due to the difficulty in estimating the potential issues in current researches.In this paper,a physics-based modeling and simulation method for the motional cable harness design is presented.The model,based on continuum mechanics,is established by analyzing the force of microelement in equilibrium.During the analysis procedure,three coordinate systems:inertial,Frenet and main-axis coordinate systems are used.By variable substitution and dimensionless processing,the equation set is discretized by differential quadrature method and subsequently becomes an overdetermined nonlinear equation set with boundary conditions solved by Levenberg-Marquardt method.With the profile of motional cable harness obtained from the integral of arithmetic solution,a motion simulation system based on"path"and"profile"as well as the experimental equipments is built.Using the same parameters as input for the simulation and the real cable harness correspondingly,the issue in designing,such as collision,can be easily found by the simulation system.This research obtains a better result which has no potential collisions by redesign,and the proposed method can be used as an accurate and efficient way in motional cable harness design work. 展开更多
关键词 motional cable harness physics-based modeling motion simulation Kirchhoff rod
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Modeling and Motion Simulation for A Flying-Wing Underwater Glider with A Symmetrical Airfoil 被引量:3
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作者 ZHAO Liang WANG Peng +1 位作者 SUN Chun-ya SONG Bao-wei 《China Ocean Engineering》 SCIE EI CSCD 2019年第3期322-332,共11页
The flying-wing underwater glider (UG), shaped as a blended wing body, is a new type of underwater vehicle and still requires further research. The shape layout and the configuration of the internal actuators of the f... The flying-wing underwater glider (UG), shaped as a blended wing body, is a new type of underwater vehicle and still requires further research. The shape layout and the configuration of the internal actuators of the flying-wing UG are different from those of "legacy gliders" which have revolving bodies, and these two factors strongly affect the dynamic performance of the vehicle. Considering these differences, we propose a new configuration of the internal actuators for the flying-wing UG and treat the flying-wing UG as a multi-body system when establishing its dynamic model. In this paper, a detailed dynamic model is presented using the Newton-Euler method for the flying-wing UG. Based on the full dynamic model, the effect of the internal actuators on the steady gliding motion of vehicle is studied theoretically, and the relationship between the state parameters of the steady gliding motion and the controlled variables is obtained by solving a set of equilibrium equations. Finally, the behaviors of two classical motion modes of the glider are analyzed based on the simulation. The simulation results demonstrate that the motion performance of the proposed flying-wing UG is satisfactory. 展开更多
关键词 flying-wing underwater GLIDER blended-wing-body dynamic modeling motion simulation STEADY motion
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Modeling and simulation of a mini AUV in spatial motion 被引量:6
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作者 王波 万磊 +1 位作者 徐玉如 秦再白 《Journal of Marine Science and Application》 2009年第1期7-12,共6页
Accurate modeling and simulation of autonomous underwater vehicle (AUV) is essential for autonomous control and maneuverability research. In this paper, a mini AUV- "MAUV-Ⅱ" was researched and the nonlinear mathe... Accurate modeling and simulation of autonomous underwater vehicle (AUV) is essential for autonomous control and maneuverability research. In this paper, a mini AUV- "MAUV-Ⅱ" was researched and the nonlinear mathematic model of the AUV in spatial motion was derived based on momentum theorem. The forces acting on AUV were resolved to several modules which were expressed in matrix form. Based on the motion model and combined with virtual reality technology, a motion simulation system was constructed. Considering the characteristic of "MAUV-Ⅱ ", the heading control and depth control were simulated by adopting S-surface control method. A long distance traveling simulation experiment based on target planning was also done. The simulation results show that the "MAUV-Ⅱ" has good spatial maneuverability, and verify the feasibility and reliability of control software. 展开更多
关键词 AUV kinematics model dynamics model motion control SIMULATION
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A Multi-Task Motion Generation Model that Fuses a Discriminator and a Generator
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作者 Xiuye Liu Aihua Wu 《Computers, Materials & Continua》 SCIE EI 2023年第7期543-559,共17页
The human motion generation model can extract structural features from existing human motion capture data,and the generated data makes animated characters move.The 3D human motion capture sequences contain complex spa... The human motion generation model can extract structural features from existing human motion capture data,and the generated data makes animated characters move.The 3D human motion capture sequences contain complex spatial-temporal structures,and the deep learning model can fully describe the potential semantic structure of human motion.To improve the authenticity of the generated human motion sequences,we propose a multi-task motion generation model that consists of a discriminator and a generator.The discriminator classifies motion sequences into different styles according to their similarity to the mean spatial-temporal templates from motion sequences of 17 crucial human joints in three-freedom degrees.And target motion sequences are created with these styles by the generator.Unlike traditional related works,our model can handle multiple tasks,such as identifying styles and generating data.In addition,by extracting 17 crucial joints from 29 human joints,our model avoids data redundancy and improves the accuracy of model recognition.The experimental results show that the discriminator of the model can effectively recognize diversified movements,and the generated data can correctly fit the actual data.The combination of discriminator and generator solves the problem of low reuse rate of motion data,and the generated motion sequences are more suitable for actual movement. 展开更多
关键词 Human motion DISCRIMINATOR GENERATOR human motion generation model multi-task processing performance motion style
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Inverted Modelling:An Effective Way to Support Motion Planning of Legged Mobile Robots
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作者 Chenyao Zhao Weizhong Guo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第1期268-279,共12页
This paper presents an effective way to support motion planning of legged mobile robots—Inverted Modelling,based on the equivalent metamorphic mechanism concept.The difference from the previous research is that we he... This paper presents an effective way to support motion planning of legged mobile robots—Inverted Modelling,based on the equivalent metamorphic mechanism concept.The difference from the previous research is that we herein invert the equivalent parallel mechanism.Assuming the leg mechanisms are hybrid links,the body of robot being considered as fixed platform,and ground as moving platform.The motion performance is transformed and measured in the body frame.Terrain and joint limits are used as input parameters to the model,resulting in the representation which is independent of terrains and particular poses in Inverted Modelling.Hence,it can universally be applied to any kind of legged robots as global motion performance framework.Several performance measurements using Inverted Modelling are presented and used in motion performance evaluation.According to the requirements of actual work like motion continuity and stability,motion planning of legged robot can be achieved using different measurements on different terrains.Two cases studies present the simulations of quadruped and hexapod robots walking on rugged roads.The results verify the correctness and effectiveness of the proposed method. 展开更多
关键词 Gait planning Inverted modelling Legged mobile robot motion planning WORKSPACE
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A nanoparticle formation model considering layered motion based on an electrical explosion experiment with AI wires
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作者 张江波 高红旭 +3 位作者 肖飞 刘威 梁泰鑫 马中亮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第1期135-146,共12页
To study the evolution of nanoparticles during Al wire electrical explosion,a nanoparticle formation model that considered layered motion was developed,and an experimental system was set up to carry out electrical exp... To study the evolution of nanoparticles during Al wire electrical explosion,a nanoparticle formation model that considered layered motion was developed,and an experimental system was set up to carry out electrical explosion experiments using 0.1 mm and 0.2 mm Al wires.The characteristic parameters and evolution process during the formation of nanoparticles were calculated and analyzed.The results show that the maximum velocities of the innermost and outermost layers are about 1200 m·s-1and 1600 m·s-1,and the velocity of the middle layer is about 1400 m·s-1,respectively.Most of the nanoparticles are formed in the temperature range of2600 K-2500 K.The characteristic temperature for the formation of Al nanoparticles is~2520K,which is also the characteristic temperature of other parameters.The size distribution range of the formed nanoparticles is 18 to 110 nm,and most of them are around 22 nm.The variation of saturated vapor pressure determines the temperature distribution range of particle nucleation.There is a minimum critical diameter of particles(~25 nm);particles smaller than the critical diameter can grow into larger particles during surface growth.Particle motion has an effect on the surface growth and aggregation process of particles,and also on the distribution area of larger-diameter particles.The simulation results are in good agreement with the experiments.We provide a method to estimate the size and distribution of nanoparticles,which is of great significance to understand the formation process of particles during the evolution of wire electrical explosion. 展开更多
关键词 electrical explosion NANOPARTICLES numerical model layered motion aluminum wire
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Technological advancements in the analysis of human motion and posture management through digital devices 被引量:2
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作者 Federico Roggio Silvia Ravalli +4 位作者 Grazia Maugeri Antonino Bianco Antonio Palma Michelino Di Rosa Giuseppe Musumeci 《World Journal of Orthopedics》 2021年第7期467-484,共18页
Technological development of motion and posture analyses is rapidly progressing,especially in rehabilitation settings and sport biomechanics.Consequently,clear discrimination among different measurement systems is req... Technological development of motion and posture analyses is rapidly progressing,especially in rehabilitation settings and sport biomechanics.Consequently,clear discrimination among different measurement systems is required to diversify their use as needed.This review aims to resume the currently used motion and posture analysis systems,clarify and suggest the appropriate approaches suitable for specific cases or contexts.The currently gold standard systems of motion analysis,widely used in clinical settings,present several limitations related to marker placement or long procedure time.Fully automated and markerless systems are overcoming these drawbacks for conducting biomechanical studies,especially outside laboratories.Similarly,new posture analysis techniques are emerging,often driven by the need for fast and non-invasive methods to obtain high-precision results.These new technologies have also become effective for children or adolescents with non-specific back pain and postural insufficiencies.The evolutions of these methods aim to standardize measurements and provide manageable tools in clinical practice for the early diagnosis of musculoskeletal pathologies and to monitor daily improvements of each patient.Herein,these devices and their uses are described,providing researchers,clinicians,orthopedics,physical therapists,and sports coaches an effective guide to use new technologies in their practice as instruments of diagnosis,therapy,and prevention. 展开更多
关键词 motion capture Gait analysis Inertial measurement unit Wearable devices Rasterstereography posture
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Complex Motion Modeling and State Estimation in Road Coordinates 被引量:1
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作者 Keyi Li Xi Chen Gongjian Zhou 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第1期19-25,共7页
Constrained modeling and state estimation have attracted much attention in recent years. This paper focuses on target motion modeling and tracking in road coordinates. An improved initialization method,which uses the ... Constrained modeling and state estimation have attracted much attention in recent years. This paper focuses on target motion modeling and tracking in road coordinates. An improved initialization method,which uses the optimal fusion of the position measurements in different directions,is presented for the constraint coordinate Kalman filter(CCKF). The CCKF is evaluated with a comprehensive comparison to the state-of-art linear equality constraint estimation methods. Numerical simulation results demonstrate the better performance of the CCKF. Then the interacting multiple model CCKF(IMM-CCKF) is proposed to manifest the advantages of the CCKF in complex motion modeling and state estimations. The effectiveness of the IMM-CCKF in maneuvering target tracking with spatial equality constraints is demonstrated by numerical experiments. 展开更多
关键词 Ground Targets motion modeling Road Constraints INITIALIZATION IMM
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Integrated modeling of spacecraft relative motion dynamics using dual quaternion 被引量:1
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作者 PENG Xuan SHI Xiaoping GONG Yupeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期367-377,共11页
To realize high accurate control of relative position and attitude between two spacecrafts, the coupling between position and attitude must be fully considered and a more precise model should be established. This pape... To realize high accurate control of relative position and attitude between two spacecrafts, the coupling between position and attitude must be fully considered and a more precise model should be established. This paper breaks the traditional divide and conquer idea, and uses a mathematical tool, namely dual quaternion to establish the integrated 6 degree-of-freedom(6-DOF) model of relative position and attitude, which describes the coupled relative motion in a compact and efficient form and needs less information of the target. Considering the complex operation rules and the unclarity of the current relative motion model in dual quaternion, necessary mathematical foundations are given at first, followed by clear and detailed modeling process and analysis. Finally a generalized proportion-derivative(PD) controller law is designed. The simulation results show that based on the integrated model established by dual quaternion, this control law can achieve a high control accuracy of relative motion. 展开更多
关键词 relative motion dual quaternion position and attitude coupling integrated modeling
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Strong motion simulation by the composite source modeling:A case study of 1679 M8.0 Sanhe-Pinggu earthquake 被引量:1
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作者 刘博研 史保平 张健 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第3期319-331,共13页
In this study, a composite source model has been used to calculate the realistic strong ground motions in Beijing area, caused by 1679 Ms8.0 earthquake in Sanhe-Pinggu. The results could provide us the useful physical... In this study, a composite source model has been used to calculate the realistic strong ground motions in Beijing area, caused by 1679 Ms8.0 earthquake in Sanhe-Pinggu. The results could provide us the useful physical parameters for the future seismic hazard analysis in this area. Considering the regional geological/geophysical background, we simulated the scenario earthquake with an associated ground motions in the area ranging from 39.3°N to 41. 1°N in latitude and from 115.35°E to 117.55°E in longitude. Some of the key factors which could influence the characteristics of strong ground motion have been discussed, and the resultant peak ground acceleration (PGA) distribution and the peak ground velocity (PGV) distribution around Beijing area also have been made as well. A comparison of the simulated result with the results derived from the attenuation relation has been made, and a sufficient discussion about the advantages and disadvantages of composite source model also has been given in this study. The numerical results, such as the PGA, PGV, peak ground displacement (PGD), and the three-component time-histories developed for Beijing area, have a potential application in earthquake engineering field and building code design, especially for the evaluation of critical constructions, government decision making and the seismic hazard assessment by financial/insurance companies. 展开更多
关键词 composite source model synthetic ground motion seismic hazard analysis
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AUV Modeling and Motion Control Strategy Design 被引量:1
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作者 王芳 万磊 +1 位作者 苏玉民 徐玉如 《Journal of Marine Science and Application》 2010年第4期379-385,共7页
To provide a suitable model for AUV simulation and control purposes, a general nonlinear dynamic model including a novel thruster hydrodynamics model was derived. Based on the modeling method, the "AUV-XX" s... To provide a suitable model for AUV simulation and control purposes, a general nonlinear dynamic model including a novel thruster hydrodynamics model was derived. Based on the modeling method, the "AUV-XX" simulation platform was established to carry out fundamental tests on its motion characteristics, stability, and controllability. A motion control strategy consisting of both position and speed control in a horizontal plane was designed for different task assignments of underwater vehicles. Combined control of heave and pitch was adopted to compensate for the reduction of vertical tunnel thrusters when the vehicle is moving at a high speed. An improved S-surface controller based on the capacitor plate model was developed with flexible gain selections made possible by different forms of restricting the error and changing the rate of the error. Simulation results show that the derived general mathematical model together with simulation platform can provide a test bed for fundamental tests of motion control. Additionally, the capacitor plate model S-surface control shows a good performance in guiding the vehicle to achieve the desired position and speed with sufficient accuracy. 展开更多
关键词 AUV general dynamic model hydrodynamics modeling simulation platform motion control
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Regional Finite-Fault Source Model for Development of Ground Motion Attenuation Relationship in Sichuan, China
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作者 Wei Jiang Zelin Cao 《Structural Durability & Health Monitoring》 EI 2023年第1期37-54,共18页
The attenuation relationship of ground motion based on seismology has always been a front subject of engineering earthquake.Among them,the regional finite-fault source model is very important.In view of this point,the... The attenuation relationship of ground motion based on seismology has always been a front subject of engineering earthquake.Among them,the regional finite-fault source model is very important.In view of this point,the general characteristics of regional seism-tectonics,including the dip and depth of the fault plane,are emphasized.According to the statistics of regional seism-tectonics and focal mechanisms in Sichuan,China,and the sensitivity of estimated peak ground acceleration(PGA)attenuation is analyzed,and the dip angle is taken as an average of 70°.Based the statistics of the upper crustal structure and the focal depth of regional earthquakes,the bottom boundary of the sedimentary cover can be used as the upper limit for estimating the depth of upper-edge.The analysis shows that this value is sensitive to PGA.Based on the analysis of geometric relations,the corresponding calculation formula is used,and a set of concepts and steps for building the regional finite-fault source model is proposed.The estimation of source parameters takes into account the uncertainty,the geometric relationship among parameters and the total energy conservation.Meanwhile,a set of reasonable models is developed,which lay a foundation for the further study of regional ground motion attenuation based on seismology. 展开更多
关键词 Ground motion attenuation relationship dip angle upper-edge depth of rupture plane source parameter regional finite-fault source model
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Takagi–Sugeno Fuzzy Modeling and Control for Effective Robotic Manipulator Motion 被引量:1
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作者 Izzat Al-Darraji Ayad AKakei +5 位作者 Ayad Ghany Ismaeel Georgios Tsaramirsis Fazal Qudus Khan Princy Randhawa Muath Alrammal Sadeeq Jan 《Computers, Materials & Continua》 SCIE EI 2022年第4期1011-1024,共14页
Robotic manipulators are widely used in applications that require fast and precise motion.Such devices,however,are prompt to nonlinear control issues due to the flexibility in joints and the friction in the motors wit... Robotic manipulators are widely used in applications that require fast and precise motion.Such devices,however,are prompt to nonlinear control issues due to the flexibility in joints and the friction in the motors within the dynamics of their rigid part.To address these issues,the Linear Matrix Inequalities(LMIs)and Parallel Distributed Compensation(PDC)approaches are implemented in the Takagy–Sugeno Fuzzy Model(T-SFM).We propose the following methodology;initially,the state space equations of the nonlinear manipulator model are derived.Next,a Takagy–Sugeno Fuzzy Model(T-SFM)technique is used for linearizing the state space equations of the nonlinear manipulator.The T-SFM controller is developed using the Parallel Distributed Compensation(PDC)method.The prime concept of the designed controller is to compensate for all the fuzzy rules.Furthermore,the Linear Matrix Inequalities(LMIs)are applied to generate adequate cases to ensure stability and control.Convex programming methods are applied to solve the developed LMIs problems.Simulations developed for the proposed model show that the proposed controller stabilized the system with zero tracking error in less than 1.5 s. 展开更多
关键词 Nonlinear robot manipulator precise fast robot motion flexible joints motor friction Takagy-Sugeno fuzzy control modeling nonlinear flexible robot system
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Three-Rigid-Body-Particle Modeling and Optimization of Trajectory and Posture for Alpine Skiing
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作者 ZHANG Yijia FEI Qing +3 位作者 YAO Xiaolan SUN Jian ZHANG Yanjun CHEN Zhen 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2024年第2期581-608,共28页
This paper presents a new study on modeling and optimization of trajectory and posture for the super-giant(SG)slalom of alpine skiing.It is the first time that a Three-Rigid-Body-Particle model based on rigorous deriv... This paper presents a new study on modeling and optimization of trajectory and posture for the super-giant(SG)slalom of alpine skiing.It is the first time that a Three-Rigid-Body-Particle model based on rigorous derivations and stability analysis is established to represent skiers trajectory and posture characteristics,as it is more accurate than the single-rigid-body model which is commonly used in existing studies.In addition,the Radau pseudospectral method is applied to solve the trajectory and posture optimization problem in order to obtain better skiing trajectory,skiing posture,and some key kinematic parameters of skiers.Moreover,this paper analyzes the effects of different body types,minimum turning radii,and flexor and extensor strength of knees and hip joint on skiing performance.Finally,based on the findings of the study,some advice about how to improve the performance of the SG slalom in view of science and technology is given to skiers and coaches for reference. 展开更多
关键词 Alpine skiing modeling posture optimization Three-Rigid-Body-Particle model trajectory optimization
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Modeling of Multi-Freedom Ship Motions in Irregular Waves with Fuzzy Neural Networks
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作者 余建星 陆培毅 +1 位作者 高喜峰 夏锦祝 《海洋工程:英文版》 2003年第2期255-264,共10页
In this paper, the neural network technology is combined with the fuzzy set theory to model the wave-induced ship motions in irregular seas. This combination makes possible the handling of a non-linear dynamic system ... In this paper, the neural network technology is combined with the fuzzy set theory to model the wave-induced ship motions in irregular seas. This combination makes possible the handling of a non-linear dynamic system with insufficient input information. The numerical results from the strip theory are used to train the networks and to demonstrate the validity of the proposed procedure. 展开更多
关键词 strip theory ship motions neural network fuzzy logic system modeling
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