In this paper,a self-developed master-slave follow-up disc cutter is used to conduct rock-breaking tests on hard sandstone samples.Different working parameters were employed in the tests(e.g.cutting depth,cutting spee...In this paper,a self-developed master-slave follow-up disc cutter is used to conduct rock-breaking tests on hard sandstone samples.Different working parameters were employed in the tests(e.g.cutting depth,cutting speed,cutting angle,and rotational speed)in order to explore their influences on cutting performance.The results indicate that the thrust,torque,vibration velocity,and roughness all increased continuously with increase of the propulsion speed and cutting depth.At the same time,the specific energy consumption was found to decrease continuously.As the rotational speed was increased,the thrust increased at first and then decreased.In contrast,the torque and roughness continuously decreased,and the specific energy consumption and vibration speed continuously increased.When the cutting angle was increased,the thrust remained unchanged.However,the torque,specific energy consumption,and vibration speed all decreased continuously,and the roughness increased continuously.The temperature of the surface of the cutting tool was found to be relatively uniformly distributed during the rock-breaking process;the highest temperatures generated were in the range of 200-300℃.As the propulsion speed,cutting depth,and cutting angle were increased,the proportion of tensile fractures produced appeared to increase and the proportion of shear fractures decreased.As the rotational speed was increased,the proportion of tensile fractures decreased and the proportion of shear fractures increased.The results could provide useful information on the rock-breaking behavior involved and can be used to offer technical support for engineers using master-slave follow-up disc cutters in the field.展开更多
This paper investigates the problem of cluster synchronization of master-slave complex net-works with time-varying delay via linear and adaptive feedback pinning controls.We need not non-delayed and delayed coupling m...This paper investigates the problem of cluster synchronization of master-slave complex net-works with time-varying delay via linear and adaptive feedback pinning controls.We need not non-delayed and delayed coupling matrices to be symmetric or irreducible.We have the advantages of using adaptive control method to reduce control gain and pinning control technology to reduce cost.By con-structing Lyapunov function,some sufficient synchronization criteria are established.Finally,numerical examples are employed to illustrate the effectiveness of the proposed approach.展开更多
In order to eliminate the meshing interference between the flexspline and circular spline after the taper deformation of the flexspline,the radial deformation difference method,major and minor axis fitting method,and ...In order to eliminate the meshing interference between the flexspline and circular spline after the taper deformation of the flexspline,the radial deformation difference method,major and minor axis fitting method,and ellipse fitting method are used to modify the tooth thickness of the flexspline and analyze the performance indexes such as the assembly stress,transmission error,and fatigue life.Firstly,the conjugate tooth profile is solved based on the quadruple-circular-arc tooth profile and modified kinematic method.Then,based on the finite element radial deformation of the flexspline,the principle and characteristics of three modification methods are analyzed,and the modification amount of each section of the flexspline tooth is calculated.Finally,the influence of the three modification methods on the performance of the harmonic drive is compared.The results show that the radial deformation difference method can initially determine the modification amount.The minimum static assembly stress is 406.22 MPa by the major and minor axis fitting method.The ellipse fitting method has the best dynamic performance,small transmission error fluctuation,a peak-to-peak value of 3.060",and a maximum fatigue life of 10^(7.558)cycles.展开更多
This study develops a contact performance-driven method for skiving face gear drives using a single cutter,eliminating the traditional need for separate cutters to reduce production costs and time.First,the mathematic...This study develops a contact performance-driven method for skiving face gear drives using a single cutter,eliminating the traditional need for separate cutters to reduce production costs and time.First,the mathematical models of the tooth flanks for the face gear drives are established based on the gear skiving processes.Then,load tooth contact analysis(LTCA)model is established to calculate the contact performance data.Next,a two-stage optimization model is employed to determine the optimal parameters of the cutting edge with improved contact performances.The effectiveness of this method is validated through simulations and rolling tests.Compared with the traditional method,the proposed method can machine both the face gear and its mating pinion with a single cutter.Simulation results show that the proposed method avoids tooth surface edge contact,with the maximum tooth surface contact stress reduced by 31.7%,the contact ratio decreases by 21.5%,and the transmission error increases by 22.3%.Rolling tests verify the consistency of tooth surface contact patterns between simulations and experiments.The proposed method provides a reference for the cutting edge design of skiving cutters for face gear pairs.展开更多
Upon flaws of current blockchain platforms of heavyweight, large capacity of ledger, and time-consuming of synchronization of data, in this paper, we proposed a new paradigm of master-slave blockchain scheme(MSB) for ...Upon flaws of current blockchain platforms of heavyweight, large capacity of ledger, and time-consuming of synchronization of data, in this paper, we proposed a new paradigm of master-slave blockchain scheme(MSB) for pervasive computing that suitable for general PC, mobile device such as smart phones or PADs to participants in the working of mining and verification, in which we separated traditional blockchain model in 2 layer defined as master node layer and a series of slavery agents layer, then we proposed 2 approaches for partially computing model(PCM) and non-computing of model(NCM) in the MSB blockchain, Finally large amounts of simulations manifest the proposed master-slave blockchain scheme is feasible, extendible and suitable for pervasive computing especially in the 5 G generation environment, and can apply in the DRM-related applications.展开更多
This paper addresses a master-slave synchro- nization strategy for complex dynamic systems based on feedback control. This strategy is applied to 3-DOF pla- nar manipulators in order to obtain synchronization in such ...This paper addresses a master-slave synchro- nization strategy for complex dynamic systems based on feedback control. This strategy is applied to 3-DOF pla- nar manipulators in order to obtain synchronization in such complicated as chaotic motions of end-effectors. A chaotic curve is selected from Duffing equation as the trajectory of master end-effector and a piecewise approximation method is proposed to accurately represent this chaotic trajectory of end-effectors. The dynamical equations of master-slave manipulators with synchronization controller are derived, and the Lyapunov stability theory is used to determine the stability of this controlled synchronization system. In numer- ical experiments, the synchronous motions of end-effectors as well as three joint angles and torques of master-slave manipulators are studied under the control of the proposed synchronization strategy. It is found that the positive gain matrix affects the implementation of synchronization con- trol strategy. This synchronization control strategy proves the synchronization＇s feasibility and controllability for com- plicated motions generated by master-slave manipulators.展开更多
The networked synchronization problem of a class of master-slave chaotic systems with time-varying communication topologies is investigated in this paper. Based on algebraic graph theory and matrix theory, a simple li...The networked synchronization problem of a class of master-slave chaotic systems with time-varying communication topologies is investigated in this paper. Based on algebraic graph theory and matrix theory, a simple linear state feedback controller is designed to synchronize the master chaotic system and the slave chaotic systems with a time- varying communication topology connection. The exponential stability of the closed-loop networked synchronization error system is guaranteed by applying Lyapunov stability theory. The derived novel criteria are in the form of linear matrix inequalities （LMIs）, which are easy to examine and tremendously reduce the computation burden from the feedback matrices. This paper provides an alternative networked secure communication scheme which can be extended conveniently. An illustrative example is given to demonstrate the effectiveness of the proposed networked synchronization method.展开更多
As a key component of injection molding,multi-cavity hot runner(MCHR)system faces the crucial problem of polymer melt filling imbalance among the cavities.The thermal imbalance in the system has been considered as the...As a key component of injection molding,multi-cavity hot runner(MCHR)system faces the crucial problem of polymer melt filling imbalance among the cavities.The thermal imbalance in the system has been considered as the leading cause.Hence,the solution may rest with the synchronization of those heating processes in MCHR system.This paper proposes a’Master-Slave’generalized predictive synchronization control(MS-GPSC)method with’Mr.Slowest’strategy for preheating stage of MCHR system.The core of the proposed method is choosing the heating process with slowest dynamics as the’Master’to track the setpoint,while the other heating processes are treated as‘Slaves’tracking the output of’Master’.This proposed method is shown to have the good ability of temperature synchronization.The corresponding analysis is conducted on parameters tuning and stability,simulations and experiments show the strategy is effective.展开更多
A 3 DOF master-slave telerobot system is established for study on force telepresence technology. A force feedback and position control scheme is adopted in the bilateral force response control system,and force fidelit...A 3 DOF master-slave telerobot system is established for study on force telepresence technology. A force feedback and position control scheme is adopted in the bilateral force response control system,and force fidelity and controllability experiments demonstrate feasibility of the con-trol system.展开更多
The fluidic oscillator is an instrument that can continuously generate a spatially sweeping jet entirely based on its internal geometry without any moving parts.However,the traditional fluidic oscillator has an inhere...The fluidic oscillator is an instrument that can continuously generate a spatially sweeping jet entirely based on its internal geometry without any moving parts.However,the traditional fluidic oscillator has an inherent limitation,that is,the spreading angle cannot be controlled independently,rather by the jet volume flow rate and internal geometry.Accordingly,two types of fluidic oscillators based on the master-slave design are developed in current study to decouple this correlation.In both designs,the master layer inherits the similar oscillation mechanisms of a sweeping jet,and the slave layer resembles a steady jet channel.The difference between the two designs is that Design A has a short diverging exit in the slave layer,but Design B adds a long interaction chamber in the exit channel to intensify flow instability.The external flow fields and governing oscillation properties of these two designs are experimentally explored with time-resolved Particle Image Velocimetry(PIV),while the internal flow dynamics and driving oscillation mechanisms are numerically investigated.By fixing the total volume flow rate,the jet spreading angle of Design A can be increased smoothly from 0°to above 100°by increasing the proportion of master layer’s flow rate from 0 to 100%.For Design B,the control authority of the master layer is significantly enhanced by adding the interaction chamber in the slave layer.In addition,the added chamber causes notable jet oscillation even when the master layer has none input.展开更多
This paper proposes an adaptive synchronization problem for the master and slave structure of linear systems with nonlinear perturbations and mixed time-varying delays comprising different discrete and distributed tim...This paper proposes an adaptive synchronization problem for the master and slave structure of linear systems with nonlinear perturbations and mixed time-varying delays comprising different discrete and distributed time delays. Using an appropriate Lyapunov-Krasovskii functional, some delay-dependent sufficient conditions and an adaptation law including the master-slave parame- ters are established for designing a delayed synchronization law in terms of linear matrix inequalities（LMIs）. The time-varying controller guarantees the H ∞ synchronization of the two coupled master and slave systems regardless of their initial states. Particularly, it is shown that the synchronization speed can be controlled by adjusting the updated gain of the synchronization signal. Two numerical examples are given to demonstrate the effectiveness of the method.展开更多
Welding seam tracking precision was decreased due to human hand tremor during the master-slave welding teleoperation. To solve this problem, a master-slave robot remote welding system was built, the system consisted o...Welding seam tracking precision was decreased due to human hand tremor during the master-slave welding teleoperation. To solve this problem, a master-slave robot remote welding system was built, the system consisted of a master manipulator with six degree of freedom （ DOF ） , an industrial computer control system and a slave Motoman HP3 J robot, and human hand tremor and digital filtering were discussed. An optimal digital filter was designed to clean human tremor signal for improving the welding seam tracking precision. The experimental results show that the digital filter suppresses the operator＇ s tremor signal.展开更多
Aiming at the weaknesses of LON bus, combining the coexistence of fieldbus and DCS (Distribu ted Control Systems) in control networks, the authors introduce a hierarchical hybrid control network design based on LON an...Aiming at the weaknesses of LON bus, combining the coexistence of fieldbus and DCS (Distribu ted Control Systems) in control networks, the authors introduce a hierarchical hybrid control network design based on LON and master slave RS 422/485 protocol. This design adopts LON as the trunk, master slave RS 422/485 control networks are connected to LON as special subnets by dedicated gateways. It is an implementation method for isomerous control network integration. Data management is ranked according to real time requirements for different network data. The core components, such as control network nodes, router and gateway, are detailed in the paper. The design utilizes both communication advantage of LonWorks technology and the more powerful control ability of universal MCUs or PLCs, thus it greatly increases system response speed and performance cost ratio.展开更多
This study aims to address the feasibility of planned islanding operation and to investigate the effect of unplanned islanding using the master-slave islanding method for controlling the distributed generation units d...This study aims to address the feasibility of planned islanding operation and to investigate the effect of unplanned islanding using the master-slave islanding method for controlling the distributed generation units during grid-connected and islanding operation. Neplan desktop power simulation tool was used for the modelling and simulation of a realistic MV network with four different distributed generation technologies (diesel, gas, hydro and wind) along with their excitation and governor control systems, while an exponential model was used to represent the loads in the network. The dynamic and steady state behavior of the four distributed generation technologies were investigated during grid-connected operation and two transition modes to the islanding situation, planned and unplanned. The obtained results that validated through various case studies have shown that a suitable planned islanding transition could provide support to critical loads at the event of electricity utility outages.展开更多
Model predictive control(MPC)has been deemed as an attractive control method in motor drives by virtue of its simple structure,convenient multi-objective optimization,and satisfactory dynamic performance.However,the s...Model predictive control(MPC)has been deemed as an attractive control method in motor drives by virtue of its simple structure,convenient multi-objective optimization,and satisfactory dynamic performance.However,the strong reliance on mathematical models seriously restrains its practical application.Therefore,improving the robustness of MPC has attained significant attentions in the last two decades,followed by which,model-free predictive control(MFPC)comes into existence.This article aims to reveal the current state of MFPC strategies for motor drives and give the categorization from the perspective of implementation.Based on this review,the principles of the reported MFPC strategies are introduced in detail,as well as the challenges encountered in technology realization.In addition,some of typical and important concepts are experimentally validated via case studies to evaluate the performance and highlight their features.Finally,the future trends of MFPC are discussed based on the current state and reported developments.展开更多
This article provides a comprehensive exploration of the current research landscape in the field of soft actuation technology applied to bio-inspired soft robots. In sharp contrast to their conventional rigid counterp...This article provides a comprehensive exploration of the current research landscape in the field of soft actuation technology applied to bio-inspired soft robots. In sharp contrast to their conventional rigid counterparts, bio-inspired soft robots are primarily constructed from flexible materials, conferring upon them remarkable adaptability and flexibility to execute a multitude of tasks in complex environments. However, the classification of their driving technology poses a significant challenge owing to the diverse array of employed driving mechanisms and materials. Here, we classify several common soft actuation methods from the perspectives of the sources of motion in bio-inspired soft robots and their bio-inspired objects, effectively filling the classification system of soft robots, especially bio-inspired soft robots. Then, we summarize the driving principles and structures of various common driving methods from the perspective of bionics, and discuss the latest developments in the field of soft robot actuation from the perspective of driving modalities and methodologies. We then discuss the application directions of bio-inspired soft robots and the latest developments in each direction. Finally, after an in-depth review of various soft bio-inspired robot driving technologies in recent years, we summarize the issues and challenges encountered in the advancement of soft robot actuation technology.展开更多
The worm wheel whose undercutting characteristic is researched is a member of offsetting normal arc-toothed cylindrical worm drive.The tooth profile of the worm in its offsetting normal section is a circular arc.The n...The worm wheel whose undercutting characteristic is researched is a member of offsetting normal arc-toothed cylindrical worm drive.The tooth profile of the worm in its offsetting normal section is a circular arc.The normal vector used to calculate the first-type limit function is determined in the natural frame without the aid of the curvature parameter of worm helicoid.The first-type limit line is ascertained via solving the nonlinear equations iteratively.It is discovered that one first-type limit line exists on the tooth surface of worm wheel by numerical simulation,and such a line is normally located out of the meshing zone.Only one intersection point exists between the first and second-types of limit lines,and this point is a lubrication weak point.The undercutting mechanism is essentially that a part of the meshing zone near the conjugated line of worm tooth crest will come into the undercutting area and will be cut off during machining the worm wheel.The machining simulation verifies the correctness of undercutting mechanism.Moreover,a convenient and practical characteristic quantity is proposed to judge whether the undercutting exists in the whole meshing zone via computing the first-type limit function values on the worm tooth crest.展开更多
Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical...Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical arms.The performance of the servo drive,which encompasses the response to the torque,efficiency,control bandwidth and the steady-state positioning accuracy,significantly influences the performance of the aviation actuation.Consequently,enhancing the control bandwidth and refining the positioning accuracy of aviation electro-mechanical actuation servo drives have emerged as a focal point of research.This paper investigates the multi-source disturbances present in aviation electro-mechanical actuation servo systems and summarizes recent research on high-performance servo control methods based on active disturbance rejection control(ADRC).We present a comprehensive overview of the research status pertaining to servo control architecture,strategies for suppressing disturbances in the current loop,and ADRC-based strategies for the position loop.We delineate the research challenges and difficulties encountered by aviation electro-mechanical actuation servo drive control technology.展开更多
基金study was supported by the National Key Research and Development Program of China(Grant No.2023YFC2907202)the National Natural Science Foundation of China(Grant No.52404116)the Postdoctoral Fellowship Program of CPSF(Grant No.GZB20240129).
文摘In this paper,a self-developed master-slave follow-up disc cutter is used to conduct rock-breaking tests on hard sandstone samples.Different working parameters were employed in the tests(e.g.cutting depth,cutting speed,cutting angle,and rotational speed)in order to explore their influences on cutting performance.The results indicate that the thrust,torque,vibration velocity,and roughness all increased continuously with increase of the propulsion speed and cutting depth.At the same time,the specific energy consumption was found to decrease continuously.As the rotational speed was increased,the thrust increased at first and then decreased.In contrast,the torque and roughness continuously decreased,and the specific energy consumption and vibration speed continuously increased.When the cutting angle was increased,the thrust remained unchanged.However,the torque,specific energy consumption,and vibration speed all decreased continuously,and the roughness increased continuously.The temperature of the surface of the cutting tool was found to be relatively uniformly distributed during the rock-breaking process;the highest temperatures generated were in the range of 200-300℃.As the propulsion speed,cutting depth,and cutting angle were increased,the proportion of tensile fractures produced appeared to increase and the proportion of shear fractures decreased.As the rotational speed was increased,the proportion of tensile fractures decreased and the proportion of shear fractures increased.The results could provide useful information on the rock-breaking behavior involved and can be used to offer technical support for engineers using master-slave follow-up disc cutters in the field.
文摘This paper investigates the problem of cluster synchronization of master-slave complex net-works with time-varying delay via linear and adaptive feedback pinning controls.We need not non-delayed and delayed coupling matrices to be symmetric or irreducible.We have the advantages of using adaptive control method to reduce control gain and pinning control technology to reduce cost.By con-structing Lyapunov function,some sufficient synchronization criteria are established.Finally,numerical examples are employed to illustrate the effectiveness of the proposed approach.
文摘In order to eliminate the meshing interference between the flexspline and circular spline after the taper deformation of the flexspline,the radial deformation difference method,major and minor axis fitting method,and ellipse fitting method are used to modify the tooth thickness of the flexspline and analyze the performance indexes such as the assembly stress,transmission error,and fatigue life.Firstly,the conjugate tooth profile is solved based on the quadruple-circular-arc tooth profile and modified kinematic method.Then,based on the finite element radial deformation of the flexspline,the principle and characteristics of three modification methods are analyzed,and the modification amount of each section of the flexspline tooth is calculated.Finally,the influence of the three modification methods on the performance of the harmonic drive is compared.The results show that the radial deformation difference method can initially determine the modification amount.The minimum static assembly stress is 406.22 MPa by the major and minor axis fitting method.The ellipse fitting method has the best dynamic performance,small transmission error fluctuation,a peak-to-peak value of 3.060",and a maximum fatigue life of 10^(7.558)cycles.
基金Project(2024YFB3410402)supported by the National Key R&D Program of ChinaProject(52075558)supported by the National Natural Science Foundation of China+2 种基金Project(2021RC3012)supported by the Science and Technology Innovation Program of Hunan Province,ChinaProject(2023CXQD050)supported by the Central South University Innovation-Driven Research Program,ChinaProject(CX20230255)supported by the Fundamental Research Funds for the Central Universities,China。
文摘This study develops a contact performance-driven method for skiving face gear drives using a single cutter,eliminating the traditional need for separate cutters to reduce production costs and time.First,the mathematical models of the tooth flanks for the face gear drives are established based on the gear skiving processes.Then,load tooth contact analysis(LTCA)model is established to calculate the contact performance data.Next,a two-stage optimization model is employed to determine the optimal parameters of the cutting edge with improved contact performances.The effectiveness of this method is validated through simulations and rolling tests.Compared with the traditional method,the proposed method can machine both the face gear and its mating pinion with a single cutter.Simulation results show that the proposed method avoids tooth surface edge contact,with the maximum tooth surface contact stress reduced by 31.7%,the contact ratio decreases by 21.5%,and the transmission error increases by 22.3%.Rolling tests verify the consistency of tooth surface contact patterns between simulations and experiments.The proposed method provides a reference for the cutting edge design of skiving cutters for face gear pairs.
基金supported by the National Natural Science Foundation of China under Grant 61272519the Research Funds of Blockchain Joint Lab between BUPT and BCTthe joint Blockchain and Security Lab between BUPT and CAPSTONE
文摘Upon flaws of current blockchain platforms of heavyweight, large capacity of ledger, and time-consuming of synchronization of data, in this paper, we proposed a new paradigm of master-slave blockchain scheme(MSB) for pervasive computing that suitable for general PC, mobile device such as smart phones or PADs to participants in the working of mining and verification, in which we separated traditional blockchain model in 2 layer defined as master node layer and a series of slavery agents layer, then we proposed 2 approaches for partially computing model(PCM) and non-computing of model(NCM) in the MSB blockchain, Finally large amounts of simulations manifest the proposed master-slave blockchain scheme is feasible, extendible and suitable for pervasive computing especially in the 5 G generation environment, and can apply in the DRM-related applications.
基金supported by the Key Project of Chinese Ministry of Education(108037)the National Natural Science Foundation of China(10402008 and 50535010)
文摘This paper addresses a master-slave synchro- nization strategy for complex dynamic systems based on feedback control. This strategy is applied to 3-DOF pla- nar manipulators in order to obtain synchronization in such complicated as chaotic motions of end-effectors. A chaotic curve is selected from Duffing equation as the trajectory of master end-effector and a piecewise approximation method is proposed to accurately represent this chaotic trajectory of end-effectors. The dynamical equations of master-slave manipulators with synchronization controller are derived, and the Lyapunov stability theory is used to determine the stability of this controlled synchronization system. In numer- ical experiments, the synchronous motions of end-effectors as well as three joint angles and torques of master-slave manipulators are studied under the control of the proposed synchronization strategy. It is found that the positive gain matrix affects the implementation of synchronization con- trol strategy. This synchronization control strategy proves the synchronization＇s feasibility and controllability for com- plicated motions generated by master-slave manipulators.
基金supported by the National Natural Science Foundation of China (Grant Nos. 60904046, 60972164, 60974071, and 60804006)the Special Fund for Basic Scientific Research of Central Colleges, Northeastern University, China (Grant No. 090604005)+2 种基金the Science and Technology Program of Shenyang (Grant No. F11-264-1-70)the Program for Liaoning Excellent Talents in University (Grant No. LJQ2011137)the Program for Liaoning Innovative Research Team in University (Grant No. LT2011019)
文摘The networked synchronization problem of a class of master-slave chaotic systems with time-varying communication topologies is investigated in this paper. Based on algebraic graph theory and matrix theory, a simple linear state feedback controller is designed to synchronize the master chaotic system and the slave chaotic systems with a time- varying communication topology connection. The exponential stability of the closed-loop networked synchronization error system is guaranteed by applying Lyapunov stability theory. The derived novel criteria are in the form of linear matrix inequalities （LMIs）, which are easy to examine and tremendously reduce the computation burden from the feedback matrices. This paper provides an alternative networked secure communication scheme which can be extended conveniently. An illustrative example is given to demonstrate the effectiveness of the proposed networked synchronization method.
基金supported in part by National Natural Science Foundation of China(62203127)Basic and Applied Basic Research Project of Guangzhou City(2023A04J1712)+1 种基金The Foshan-HKUST Projects Program(FSUST19-FYTRI01)GDAS’Project of Science and Technology Development(2020GDASYL-20200202001).
文摘As a key component of injection molding,multi-cavity hot runner(MCHR)system faces the crucial problem of polymer melt filling imbalance among the cavities.The thermal imbalance in the system has been considered as the leading cause.Hence,the solution may rest with the synchronization of those heating processes in MCHR system.This paper proposes a’Master-Slave’generalized predictive synchronization control(MS-GPSC)method with’Mr.Slowest’strategy for preheating stage of MCHR system.The core of the proposed method is choosing the heating process with slowest dynamics as the’Master’to track the setpoint,while the other heating processes are treated as‘Slaves’tracking the output of’Master’.This proposed method is shown to have the good ability of temperature synchronization.The corresponding analysis is conducted on parameters tuning and stability,simulations and experiments show the strategy is effective.
文摘A 3 DOF master-slave telerobot system is established for study on force telepresence technology. A force feedback and position control scheme is adopted in the bilateral force response control system,and force fidelity and controllability experiments demonstrate feasibility of the con-trol system.
基金financial support from the National Natural Science Foundation of China(Nos.12072196 and 11702172)Science and Technology Commission of Shanghai Municipality(No.19JC1412900)+1 种基金Aeronautics Power Foundation(No.6141B09050393)Key Laboratory of Aerodynamic Noise Control(No.ANCL20190106)extended to this study。
文摘The fluidic oscillator is an instrument that can continuously generate a spatially sweeping jet entirely based on its internal geometry without any moving parts.However,the traditional fluidic oscillator has an inherent limitation,that is,the spreading angle cannot be controlled independently,rather by the jet volume flow rate and internal geometry.Accordingly,two types of fluidic oscillators based on the master-slave design are developed in current study to decouple this correlation.In both designs,the master layer inherits the similar oscillation mechanisms of a sweeping jet,and the slave layer resembles a steady jet channel.The difference between the two designs is that Design A has a short diverging exit in the slave layer,but Design B adds a long interaction chamber in the exit channel to intensify flow instability.The external flow fields and governing oscillation properties of these two designs are experimentally explored with time-resolved Particle Image Velocimetry(PIV),while the internal flow dynamics and driving oscillation mechanisms are numerically investigated.By fixing the total volume flow rate,the jet spreading angle of Design A can be increased smoothly from 0°to above 100°by increasing the proportion of master layer’s flow rate from 0 to 100%.For Design B,the control authority of the master layer is significantly enhanced by adding the interaction chamber in the slave layer.In addition,the added chamber causes notable jet oscillation even when the master layer has none input.
文摘This paper proposes an adaptive synchronization problem for the master and slave structure of linear systems with nonlinear perturbations and mixed time-varying delays comprising different discrete and distributed time delays. Using an appropriate Lyapunov-Krasovskii functional, some delay-dependent sufficient conditions and an adaptation law including the master-slave parame- ters are established for designing a delayed synchronization law in terms of linear matrix inequalities（LMIs）. The time-varying controller guarantees the H ∞ synchronization of the two coupled master and slave systems regardless of their initial states. Particularly, it is shown that the synchronization speed can be controlled by adjusting the updated gain of the synchronization signal. Two numerical examples are given to demonstrate the effectiveness of the method.
基金This research is supported by National Natural Science Foundation of China （No. 50905043）.
文摘Welding seam tracking precision was decreased due to human hand tremor during the master-slave welding teleoperation. To solve this problem, a master-slave robot remote welding system was built, the system consisted of a master manipulator with six degree of freedom （ DOF ） , an industrial computer control system and a slave Motoman HP3 J robot, and human hand tremor and digital filtering were discussed. An optimal digital filter was designed to clean human tremor signal for improving the welding seam tracking precision. The experimental results show that the digital filter suppresses the operator＇ s tremor signal.
文摘Aiming at the weaknesses of LON bus, combining the coexistence of fieldbus and DCS (Distribu ted Control Systems) in control networks, the authors introduce a hierarchical hybrid control network design based on LON and master slave RS 422/485 protocol. This design adopts LON as the trunk, master slave RS 422/485 control networks are connected to LON as special subnets by dedicated gateways. It is an implementation method for isomerous control network integration. Data management is ranked according to real time requirements for different network data. The core components, such as control network nodes, router and gateway, are detailed in the paper. The design utilizes both communication advantage of LonWorks technology and the more powerful control ability of universal MCUs or PLCs, thus it greatly increases system response speed and performance cost ratio.
文摘This study aims to address the feasibility of planned islanding operation and to investigate the effect of unplanned islanding using the master-slave islanding method for controlling the distributed generation units during grid-connected and islanding operation. Neplan desktop power simulation tool was used for the modelling and simulation of a realistic MV network with four different distributed generation technologies (diesel, gas, hydro and wind) along with their excitation and governor control systems, while an exponential model was used to represent the loads in the network. The dynamic and steady state behavior of the four distributed generation technologies were investigated during grid-connected operation and two transition modes to the islanding situation, planned and unplanned. The obtained results that validated through various case studies have shown that a suitable planned islanding transition could provide support to critical loads at the event of electricity utility outages.
基金supported in part by the National Natural Science Foundation of China under Grant 52077002。
文摘Model predictive control(MPC)has been deemed as an attractive control method in motor drives by virtue of its simple structure,convenient multi-objective optimization,and satisfactory dynamic performance.However,the strong reliance on mathematical models seriously restrains its practical application.Therefore,improving the robustness of MPC has attained significant attentions in the last two decades,followed by which,model-free predictive control(MFPC)comes into existence.This article aims to reveal the current state of MFPC strategies for motor drives and give the categorization from the perspective of implementation.Based on this review,the principles of the reported MFPC strategies are introduced in detail,as well as the challenges encountered in technology realization.In addition,some of typical and important concepts are experimentally validated via case studies to evaluate the performance and highlight their features.Finally,the future trends of MFPC are discussed based on the current state and reported developments.
基金Fundamental Research Funds for the Central Universities(No.2024JBMC011)Aeronautical Science Foundation of China(No.2024Z0560M5001).
文摘This article provides a comprehensive exploration of the current research landscape in the field of soft actuation technology applied to bio-inspired soft robots. In sharp contrast to their conventional rigid counterparts, bio-inspired soft robots are primarily constructed from flexible materials, conferring upon them remarkable adaptability and flexibility to execute a multitude of tasks in complex environments. However, the classification of their driving technology poses a significant challenge owing to the diverse array of employed driving mechanisms and materials. Here, we classify several common soft actuation methods from the perspectives of the sources of motion in bio-inspired soft robots and their bio-inspired objects, effectively filling the classification system of soft robots, especially bio-inspired soft robots. Then, we summarize the driving principles and structures of various common driving methods from the perspective of bionics, and discuss the latest developments in the field of soft robot actuation from the perspective of driving modalities and methodologies. We then discuss the application directions of bio-inspired soft robots and the latest developments in each direction. Finally, after an in-depth review of various soft bio-inspired robot driving technologies in recent years, we summarize the issues and challenges encountered in the advancement of soft robot actuation technology.
基金Projects(52205069,52075083,52304049)supported by the National Natural Science Foundation of ChinaProject(2021-BS-164)supported by the Liaoning Province Doctoral Research Startup Fund,China+2 种基金Project(LJKZ0264)supported by the Science and Technology Research Projects of Education Department of Liaoning Province,ChinaProject(G2022003010L)supported by the High-end Foreign Experts Recruitment Plan of ChinaProject(E2021203095)supported by the Natural Science Foundation for Young Scholars of Hebei Province,China。
文摘The worm wheel whose undercutting characteristic is researched is a member of offsetting normal arc-toothed cylindrical worm drive.The tooth profile of the worm in its offsetting normal section is a circular arc.The normal vector used to calculate the first-type limit function is determined in the natural frame without the aid of the curvature parameter of worm helicoid.The first-type limit line is ascertained via solving the nonlinear equations iteratively.It is discovered that one first-type limit line exists on the tooth surface of worm wheel by numerical simulation,and such a line is normally located out of the meshing zone.Only one intersection point exists between the first and second-types of limit lines,and this point is a lubrication weak point.The undercutting mechanism is essentially that a part of the meshing zone near the conjugated line of worm tooth crest will come into the undercutting area and will be cut off during machining the worm wheel.The machining simulation verifies the correctness of undercutting mechanism.Moreover,a convenient and practical characteristic quantity is proposed to judge whether the undercutting exists in the whole meshing zone via computing the first-type limit function values on the worm tooth crest.
基金supported by the National Natural Science Foundation of China(Nos.52177059 and 52407064).
文摘Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical arms.The performance of the servo drive,which encompasses the response to the torque,efficiency,control bandwidth and the steady-state positioning accuracy,significantly influences the performance of the aviation actuation.Consequently,enhancing the control bandwidth and refining the positioning accuracy of aviation electro-mechanical actuation servo drives have emerged as a focal point of research.This paper investigates the multi-source disturbances present in aviation electro-mechanical actuation servo systems and summarizes recent research on high-performance servo control methods based on active disturbance rejection control(ADRC).We present a comprehensive overview of the research status pertaining to servo control architecture,strategies for suppressing disturbances in the current loop,and ADRC-based strategies for the position loop.We delineate the research challenges and difficulties encountered by aviation electro-mechanical actuation servo drive control technology.
