The accuracy of center height detection for corrugated beam guardrails is significantly affected by robot posture in the mobile highway guardrail detection systems based on structured light vision.To address the probl...The accuracy of center height detection for corrugated beam guardrails is significantly affected by robot posture in the mobile highway guardrail detection systems based on structured light vision.To address the problem,this paper proposes an integrated calibration method for structured light vision sensors.In the proposed system,the sensor is mounted on a crawler-type mobile robot,which scans and measures the center height of guardrails while in motion.However,due to external disturbances such as uneven road surfaces and vehicle vibrations,the posture of the robot may deviate,causing displacement of the sensor platform and resulting in spatial 3D measurement errors.To overcome this issue,the system integrates inertial measurement unit(IMU)data into the sensor calibration process,enabling realtime correction of posture deviations through sensor fusion.This approach achieves a unified calibration of the structured light vision system,effectively compensates for posture-induced errors,and enhances detection accuracy.A prototype was developed and tested in both laboratory and real highway environments.Experimental results demonstrate that the proposed method enables accurate center height detection of guardrails under complex road conditions,significantly reduces posture-related measurement errors,and greatly improves the efficiency and reliability of traditional detection methods.展开更多
With the rapid development of the intelligent manufacturing industry,the demand for technical talents in industrial robot technology has become increasingly urgent.Focusing on the application value of virtual simulati...With the rapid development of the intelligent manufacturing industry,the demand for technical talents in industrial robot technology has become increasingly urgent.Focusing on the application value of virtual simulation technology in the practical teaching of industrial robot major and combining with the national vocational education reform policies,this paper explores the innovative role of virtual simulation technology in the practical teaching model from four dimensions:teaching cost optimization,safety improvement,scenario expansion,and evaluation innovation.The research shows that virtual simulation technology can effectively solve the“three highs and three difficulties”problems in traditional practical teaching,promote the in-depth development of the integration of industry and education,and provide strong support for cultivating high-quality technical and skilled talent in the field of industrial robots.展开更多
Fluxgate current sensors(FGCSs)are increasingly employed in power systems due to their high-precision characteristics,yet their measurement flexibility remains constrained by conventional closed-core designs.To addres...Fluxgate current sensors(FGCSs)are increasingly employed in power systems due to their high-precision characteristics,yet their measurement flexibility remains constrained by conventional closed-core designs.To address this limitation,we proposed a split-core sensor structure comprising four magnetic core strips,which achieved non-intrusive current measurement while maintaining detection accuracy.An analytical model of the induced electromotive force was established based on the probe’s geometric configuration,followed by finite element simulations to optimize key parameters including core radius,core width,excitation coil turns,and sensing coil configuration.A complete prototype integrating the measurement probe,excitation circuit,and signal processing circuitry was developed and experimentally validated.The experimental results show a sensitivity of 0.1099 V/A,a hysteresis error of 0.559%,and a repeatability error of 1.574%over a measurement range of±10 A.After polynomial fitting-based error compensation,the nonlinearity error was reduced to 0.208%,achieving performance comparable to closed-core sensors.This work provided a practical solution for applications demanding both high measurement accuracy and installation flexibility.展开更多
This research paper tackles the complexities of achieving global fuzzy consensus in leader-follower systems in robotic systems,focusing on robust control systems against an advanced signal attack that integrates senso...This research paper tackles the complexities of achieving global fuzzy consensus in leader-follower systems in robotic systems,focusing on robust control systems against an advanced signal attack that integrates sensor and actuator disturbances within the dynamics of follower robots.Each follower robot has unknown dynamics and control inputs,which expose it to the risks of both sensor and actuator attacks.The leader robot,described by a secondorder,time-varying nonlinear model,transmits its position,velocity,and acceleration information to follower robots through a wireless connection.To handle the complex setup and communication among robots in the network,we design a robust hybrid distributed adaptive control strategy combining the effect of sensor and actuator attack,which ensures asymptotic consensus,extending beyond conventional bounded consensus results.The proposed framework employs fuzzy logic systems(FLSs)as proactive controllers to estimate unknown nonlinear behaviors,while also effectively managing sensor and actuator attacks,ensuring stable consensus among all agents.To counter the impact of the combined signal attack on follower dynamics,a specialized robust control mechanism is designed,sustaining system stability and performance under adversarial conditions.The efficiency of this control strategy is demonstrated through simulations conducted across two different directed communication topologies,underscoring the protocol’s adaptability,resilience,and effectiveness in maintaining global consensus under complex attack scenarios.展开更多
Based on the character of the modular self-reconfigurable （MSR） robot, a novel homogeneous and lattice MSR robot, M-Cubes, was designed. Each module unit of the robot has 12 freedoms and is composed of six rotary jo...Based on the character of the modular self-reconfigurable （MSR） robot, a novel homogeneous and lattice MSR robot, M-Cubes, was designed. Each module unit of the robot has 12 freedoms and is composed of six rotary joints and one cubic link. An attached/detached mechanism was designed on the rotary joints. A novel space transmitting system was placed on the inner portion of the cubic link. A motor separately transmitted torque to the six joints which were distributed equally on six surfaces of the cubic link. The example of a basic motion for the module was demonstrated. The result shows that the robot is concise and compact in structure, highly efficient in transmission, credible in connecting, and simple in controlling. At the same time, a simulator is developed to graphically design the system configuration, the reconfiguration process and the motion of cluster modules. The character of local action for the cellular automata （CA） is utilized. Each module is simplified as a cell. The transition rules of the CA are developed to combine with the genetic algorithm （GA） and applied to each module to accomplish distributed control. Simulation proves that the method is effective and feasible.展开更多
This paper proposes a method that rotation angle of servo motor and distance values of ultrasonic sensor are used for tracking an object in real-time while the robot keeps regular distance.Object detection distance wi...This paper proposes a method that rotation angle of servo motor and distance values of ultrasonic sensor are used for tracking an object in real-time while the robot keeps regular distance.Object detection distance widens by using ultrasonic sensors and object recognition,and movement of robot is controlled by angle of servo motor and distance of ultrasonic sensors.Not adopting the existing tracking methods:camera,laser-infrared(LRF)and many ultrasonic sensors,the proposed method proves that it is possible to track object using ultrasonic sensor and servo motor.Trajectory of robot is represented and analysed according to movement of object in limited conditions.展开更多
In this paper,three dimensions kinematics and kinetics simulation are discussed for hardware realization of a physical biped walking-chair robot.The direct and inverse close-form kinematics solution of the biped walki...In this paper,three dimensions kinematics and kinetics simulation are discussed for hardware realization of a physical biped walking-chair robot.The direct and inverse close-form kinematics solution of the biped walking-chair robot is deduced.Several gaits are realized with the kinematics solution,including walking straight on level floor,going up stair,squatting down and standing up.Zero Moment Point(ZMP)equation is analyzed considering the movement of the crew.The simulated biped walking-chair robot is used for mechanical design,gaits development and validation before they are tested on real robot.展开更多
Predicting the performance of intelligent multi-robot systems is advantageous because running physical experiments with teams of robots can be costly and time consuming. Controlling for every factor can be difficult i...Predicting the performance of intelligent multi-robot systems is advantageous because running physical experiments with teams of robots can be costly and time consuming. Controlling for every factor can be difficult in the presence of minor disparities (i.e. battery charge). Access to a variety of environmental configurations and hardware choices is prohibitive in many cases. With the eminent need for dependable robot controllers and algorithms, it is essential to understand when real robot performance can be accurately predicted. New prediction methods must account for the effects of digital and physical interaction between the robots that are more complex than just collision detection of 2D or physics-based 3D models. In this paper, we identify issues in predicting multi-robot performance and present examples of statistical and model-based simulation methods and their applicability to multi-robot systems. Even when sensor noise, latency and environmental configuration are modeled in some complexity, multi-robot systems interject interference and messaging latency, causing many prediction systems to fail to correlate to absolute or relative performance. We support this supposition by comparing results from 3D physics-based simulations to identical experiments with a physical robot team for a coverage task.展开更多
Soft robots have become important members of the robot community with many potential applications owing to their unique flexibility and security embedded at the material level.An increasing number of researchers are i...Soft robots have become important members of the robot community with many potential applications owing to their unique flexibility and security embedded at the material level.An increasing number of researchers are interested in their designing,manufacturing,modeling,and control.However,the dynamic simulation of soft robots is difficult owing to their infinite degrees of freedom and nonlinear characteristics that are associated with soft materials and flexible geometric structures.In this study,a novel multi-flexible body dynamic modeling and simulation technique is introduced for soft robots.Various actuators for soft robots are modeled in a virtual environment,including soft cable-driven,spring actuation,and pneumatic driving.A pneumatic driving simulation was demonstrated by the bending modules with different materials.A cable-driven soft robot arm prototype and a cylindrical soft module actuated by shape memory alley springs inspired by an octopus were manufactured and used to validate the simulation model,and the experimental results demonstrated adequate accuracy.The proposed technique can be widely applied for the modeling and dynamic simulation of other soft robots,including hybrid actuated robots and rigid-flexible coupling robots.This study also provides a fundamental framework for simulating soft mobile robots and soft manipulators in contact with the environment.展开更多
Robot＇s dynamic motion error and on-line compensation based on multi-axis force sensor are dealt with.It is revealed that the reasons of the error are formed and the relations of the error are delivered.A motion equa...Robot＇s dynamic motion error and on-line compensation based on multi-axis force sensor are dealt with.It is revealed that the reasons of the error are formed and the relations of the error are delivered.A motion equation of robot＇s termination with the error is established,and then,an error matrix and an error compensation matrix of the motion equation are also defined.An on-line error＇s compensation method is put forward to decrease the displacement error,which is a degree of millimeter,shown by the result of simulation of PUMA562 robot.展开更多
A mobile robot developed by Wuhan University for full-path hotline inspection on 220 kV transmission lines was presented. With 4 rotating joints and 2 translational ones, such robot is capable of traveling along non- ...A mobile robot developed by Wuhan University for full-path hotline inspection on 220 kV transmission lines was presented. With 4 rotating joints and 2 translational ones, such robot is capable of traveling along non- obstaclestraight-line segment and surmounting straight-line segment obstacles as well as transferring between two spans automatically. Lagrange’s equations were utilized to derive dynamic equations of all the links, including items of inertia, coupling inertia, Coriolis acceleration, centripetal acceleration and gravity. And a dynamic response experiment on elemental motions of robot prototype’s travelling along non-obstacle straight-line segment and surmounting obstacles was performed on 220 kV 1∶1 simulative overhanging transmission-line in laboratory. In addition, dynamic numerical simulation was conducted in the corresponding condition. Comparison and analysis on results of experiment and numerical simulation have validated theoretical model and simulation resolution. Therefore, the dynamic model formed hereunder can be used for the study of robot control.展开更多
The motion simulation of arc welding robot is the basis of the system of robot off-line programming, and it has been one of the important research directions. The UGNX 4. 0 is adopted to establish 3D simulating model ...The motion simulation of arc welding robot is the basis of the system of robot off-line programming, and it has been one of the important research directions. The UGNX 4. 0 is adopted to establish 3D simulating model of MOTOMAN-HP6 arc welding robot. The kinematic model under link-pole coordinate system is established by the second development function offered by UG/OPEN API and the method of programming using VC ＋＋ 6. 0. The methods of founding model and operational procedures are introduced, which provides a good basis for off-line programming technique under Unigraphies condition.展开更多
When robot is at singular configuration, the limited hand velocity wouldrequire some joints with infeasible speeds so as to lead unsafely of the system. A method of solvingthe approximate velocity of joint near singul...When robot is at singular configuration, the limited hand velocity wouldrequire some joints with infeasible speeds so as to lead unsafely of the system. A method of solvingthe approximate velocity of joint near singular configuration point by adding damped vector isproposed and a modified algorithm is provided. With the analysis of J^(-1) the singularconfigurations of 6R robot are divided into structure boundary singularity , boundary singularity ,inner singularity and wrist singularity. The conditions of singularities of the robot have beenascertained. The computer simulations of the singularities of the robot are developed, which havemany advantages over previous description methods of the singular configurations of robot. With thehelp of boundary singularity analysis, a application in welding trajectory planning checking of therobot has been carried out and the simulation result proved visualized and useful.展开更多
In order to provide a theoretical basis for methane sensor placement in the vertical direction of a tunnel,the software Fluent was used to simulate methane distribution. A geometric roadway model was established and d...In order to provide a theoretical basis for methane sensor placement in the vertical direction of a tunnel,the software Fluent was used to simulate methane distribution. A geometric roadway model was established and divided by grids. Methane distribution in both level and vertical sections was simulated using a realizable k-ε model with the Fluent software according to a conservation equation in a turbulent state,a turbulent kinetic energy equation and a turbulent dissipation rate equation. The realizable k-ε model and the Fluent software were used to simulate methane distribution according to the principle of the conservation equation in a state of turbulent flow. The results show that after overflow-ing,a methane level with a certain thickness is formed. Methane density curves at three specific levels were internally consistent and methane density at higher levels is denser than that at lower levels. Methane distribution becomes thinner in the direction of wind and methane in the vertical direction becomes uniform if wind speed is high. The distance be-tween sensors and roof should be less than 300 mm which is in agreement with mine safety regulations.展开更多
In the underwater environment, many visual sensors don’t work, and many sensors which work well for robots working in space or on land can not be used underwater. Therefore, an optical fiber slide tactile sensor was ...In the underwater environment, many visual sensors don’t work, and many sensors which work well for robots working in space or on land can not be used underwater. Therefore, an optical fiber slide tactile sensor was designed based on the inner modulation mechanism of optical fibers. The principles and structure of the sensor are explained in detail. Its static and dynamic characteristics were analyzed theoretically and then simulated. A dynamic characteristic model was built and the simulation made using the GA based neural network. In order to improve sensor response, the recognition model of the sensor was designed based on the ‘inverse solution’ principle of neural networks, increasing the control precision and the sensitivity of the manipulator.展开更多
In order to simulate the gait of human walking on different terrains a new robot with six degrees of freedom was proposed. Based on sand bearing characteristic compliance control was introduced to control system in ho...In order to simulate the gait of human walking on different terrains a new robot with six degrees of freedom was proposed. Based on sand bearing characteristic compliance control was introduced to control system in horizontal and vertical movement directions at the end of the robot,and position control in attitude. With Matlab/Simulink toolbox,the system control models were established,and the bearing characteristics of rigid ground,hard sand,soft sand and softer sand were simulated. The results show that 0,0.62,0.89 and 1.12 mm are the maximal subsidences of the four kinds of ground along the positive direction of x-axis,respectively,and 0,-0.96,-1.99 and -3.00 mm are the maximal subsidences along the negative direction of x-axis,respectively. Every subsidence along y-axis is negative,and 0,-4.12,-8.23 and -12.01 mm are the maximal subsidences of the four kinds of ground,respectively. Simulation results show that the subsidence of footboard points to inferior anterior in early stage of stand phase,while points to posterior aspect in late stage. The subsidence tends to point to posterior aspect in the whole. These results are basically consistent with the gait characteristics of human walking on sand. Gait simulation of the robot for human walking on sand is achieved.展开更多
A passive simulation method based on the six degrees of freedom(6-DOF)model and dynamic mesh is proposed according to the working principle to study the dynamic characteristics of the turbine flow sensors.This simulat...A passive simulation method based on the six degrees of freedom(6-DOF)model and dynamic mesh is proposed according to the working principle to study the dynamic characteristics of the turbine flow sensors.This simulation method controls the six degrees of freedom of the impeller using the user-defined functions(UDF)program so that it can only rotate under the impact of fluid.The impeller speed can be calculated in real-time,and the inlet speed can be set with time to obtain the dynamic performance of the turbine flow sensors.Based on this simulation method,three turbine flow sensors with different diameters were simulated,and the reliability of the simulation method was verified by both steady-state and unsteady-state experiments.The results show that the trend of meter factor with flow rate acquired from the simulation is close to the experimental results.The deviation between the simulation and experiment results is low,with a maximum deviation of 2.88%.In the unsteady simulation study,the impeller speed changed with the inlet velocity of the turbine flow sensor,showing good tracking performance.The passive simulation method can be used to predict the dynamic performance of the turbine flow sensor.展开更多
Because of the special underwater environment, many sensors used well in robots working in space or on the land can not be used in the underwater. So an optical fiber type slide tactile sensor is designed by the inner...Because of the special underwater environment, many sensors used well in robots working in space or on the land can not be used in the underwater. So an optical fiber type slide tactile sensor is designed by the inner modulation mechanism of the intensity type optical fiber. The principle and structure of the sensor are introduced in detail. The static and dynamic characteristics are analyzed theoretically and experimentally. The dynamic characteristic model is built and the simulation is made by using genetic algorithm based on neural network. In order to use the sensor perfectly, the recognition model of the sensor is built on the basis of the principle of “inverse solution” using neural networks. The control precision and sensitivity of the manipulator are improved.展开更多
The purpose of this article is to explore the cause of the over-response phenomenon of fiber x-ray sensor.The sensor is based on a length of PMMA fiber,whose end is filled with the scintillation material Gd_(2)O_(2)S:...The purpose of this article is to explore the cause of the over-response phenomenon of fiber x-ray sensor.The sensor is based on a length of PMMA fiber,whose end is filled with the scintillation material Gd_(2)O_(2)S:Tb.The Monte Carlo simulation software GEANT4 uses the phase space file provided by the International Atomic Energy Agency(IAEA),by irradiating the fiber x-ray sensor in the water phantom,counting the fluorescence signal of the optical fiber x-ray sensor after propagation through the fiber.In addition,the number of Cerenkov photons propagating through the fiber is also counted.Comparing this article with previous research,we believe that one of the reasons for the over-response of the fiber x-ray sensor is the non-linear response of the deposition energy of the scintillator to the fluorescence.By establishing a region of interest and counting the x-rays in this region,the simulation results show that the counted number of x-rays that may affect the fiber x-ray sensor is the biggest in the area of interest at a water depth of 5 cm.This result is close to the maximum dose point of the experimental and simulated percentage depth dose(PDD) curve of fiber x-ray sensor.Therefore,the second reason of the over-response phenomenon is believed to be fact that the inorganic materials such as Gd_(2)O_(2)S:Tb have larger effective atomic numbers,so the fiber x-ray sensors will cause more collisions with x-ray in a low energy region of 0.1 MeV-1.5 MeV.展开更多
In order to observe the change and fluctuation in flow and pressure of a hydraulic quadruped robot＇s hydraulic system when the robot walks on trot gait,a co-simulation method based on ADAMS and AMESim is proposed. Fi...In order to observe the change and fluctuation in flow and pressure of a hydraulic quadruped robot＇s hydraulic system when the robot walks on trot gait,a co-simulation method based on ADAMS and AMESim is proposed. Firstly,the change rule in each swing angle of the hydraulic quadruped robot＇s four legs is analyzed and converted to the displacement change of the hydraulic cylinder by calculating their geometric relationship.Secondly,the robot＇s dynamic model is built in ADAMS and its hydraulic and control system models are built in AMESim. The displacement change of the hydraulic cylinder in the hydraulic system is used as the driving function of the dynamics model in ADAMS,and the driving force of the dynamics model is used as the loads of the hydraulic system in AMESim. By introducing the PID closed-loop control in the control system,the co-simulation between hydraulic system and mechanical system is implemented. Finally,the curve of hydraulic cylinders＇ loads,flow and pressure are analyzed and the results show that they fluctuate highly in accordance with the real situation. The study provides data support for the development of a hydraulic quadruped robot＇s physical prototype.展开更多
基金Supported by the Special Fund for Basic Scientific Research of Central-Level Public Welfare Scientific Research Institutes(2024-9007)。
文摘The accuracy of center height detection for corrugated beam guardrails is significantly affected by robot posture in the mobile highway guardrail detection systems based on structured light vision.To address the problem,this paper proposes an integrated calibration method for structured light vision sensors.In the proposed system,the sensor is mounted on a crawler-type mobile robot,which scans and measures the center height of guardrails while in motion.However,due to external disturbances such as uneven road surfaces and vehicle vibrations,the posture of the robot may deviate,causing displacement of the sensor platform and resulting in spatial 3D measurement errors.To overcome this issue,the system integrates inertial measurement unit(IMU)data into the sensor calibration process,enabling realtime correction of posture deviations through sensor fusion.This approach achieves a unified calibration of the structured light vision system,effectively compensates for posture-induced errors,and enhances detection accuracy.A prototype was developed and tested in both laboratory and real highway environments.Experimental results demonstrate that the proposed method enables accurate center height detection of guardrails under complex road conditions,significantly reduces posture-related measurement errors,and greatly improves the efficiency and reliability of traditional detection methods.
文摘With the rapid development of the intelligent manufacturing industry,the demand for technical talents in industrial robot technology has become increasingly urgent.Focusing on the application value of virtual simulation technology in the practical teaching of industrial robot major and combining with the national vocational education reform policies,this paper explores the innovative role of virtual simulation technology in the practical teaching model from four dimensions:teaching cost optimization,safety improvement,scenario expansion,and evaluation innovation.The research shows that virtual simulation technology can effectively solve the“three highs and three difficulties”problems in traditional practical teaching,promote the in-depth development of the integration of industry and education,and provide strong support for cultivating high-quality technical and skilled talent in the field of industrial robots.
基金supported by Yunnan Fundamental Research Projects(No.202301AT070181)Yunnan Fundamental Research Projects(No.202401CF070126)+1 种基金Xingdian Talent Support Program of Yunnan Province(No.KKRD202203070)Yunnan High level Science and Technology Talents and Innovation Team Selection Special Project(No.202405AS350001).
文摘Fluxgate current sensors(FGCSs)are increasingly employed in power systems due to their high-precision characteristics,yet their measurement flexibility remains constrained by conventional closed-core designs.To address this limitation,we proposed a split-core sensor structure comprising four magnetic core strips,which achieved non-intrusive current measurement while maintaining detection accuracy.An analytical model of the induced electromotive force was established based on the probe’s geometric configuration,followed by finite element simulations to optimize key parameters including core radius,core width,excitation coil turns,and sensing coil configuration.A complete prototype integrating the measurement probe,excitation circuit,and signal processing circuitry was developed and experimentally validated.The experimental results show a sensitivity of 0.1099 V/A,a hysteresis error of 0.559%,and a repeatability error of 1.574%over a measurement range of±10 A.After polynomial fitting-based error compensation,the nonlinearity error was reduced to 0.208%,achieving performance comparable to closed-core sensors.This work provided a practical solution for applications demanding both high measurement accuracy and installation flexibility.
文摘This research paper tackles the complexities of achieving global fuzzy consensus in leader-follower systems in robotic systems,focusing on robust control systems against an advanced signal attack that integrates sensor and actuator disturbances within the dynamics of follower robots.Each follower robot has unknown dynamics and control inputs,which expose it to the risks of both sensor and actuator attacks.The leader robot,described by a secondorder,time-varying nonlinear model,transmits its position,velocity,and acceleration information to follower robots through a wireless connection.To handle the complex setup and communication among robots in the network,we design a robust hybrid distributed adaptive control strategy combining the effect of sensor and actuator attack,which ensures asymptotic consensus,extending beyond conventional bounded consensus results.The proposed framework employs fuzzy logic systems(FLSs)as proactive controllers to estimate unknown nonlinear behaviors,while also effectively managing sensor and actuator attacks,ensuring stable consensus among all agents.To counter the impact of the combined signal attack on follower dynamics,a specialized robust control mechanism is designed,sustaining system stability and performance under adversarial conditions.The efficiency of this control strategy is demonstrated through simulations conducted across two different directed communication topologies,underscoring the protocol’s adaptability,resilience,and effectiveness in maintaining global consensus under complex attack scenarios.
文摘Based on the character of the modular self-reconfigurable （MSR） robot, a novel homogeneous and lattice MSR robot, M-Cubes, was designed. Each module unit of the robot has 12 freedoms and is composed of six rotary joints and one cubic link. An attached/detached mechanism was designed on the rotary joints. A novel space transmitting system was placed on the inner portion of the cubic link. A motor separately transmitted torque to the six joints which were distributed equally on six surfaces of the cubic link. The example of a basic motion for the module was demonstrated. The result shows that the robot is concise and compact in structure, highly efficient in transmission, credible in connecting, and simple in controlling. At the same time, a simulator is developed to graphically design the system configuration, the reconfiguration process and the motion of cluster modules. The character of local action for the cellular automata （CA） is utilized. Each module is simplified as a cell. The transition rules of the CA are developed to combine with the genetic algorithm （GA） and applied to each module to accomplish distributed control. Simulation proves that the method is effective and feasible.
基金The MKE(The Ministry of Knowledge Economy),Korea,under the Human Resources Development Program for Robotics Support Program supervised by the NIPA(National IT Industry Promotion Agency)(NIPA-2012-H1502-12-1002)The MKE,Korea,under the ITRC(Infor mation Technology Research Center)Support Program supervised by the NIPA(NI-PA-2012-H0301-12-2006)
文摘This paper proposes a method that rotation angle of servo motor and distance values of ultrasonic sensor are used for tracking an object in real-time while the robot keeps regular distance.Object detection distance widens by using ultrasonic sensors and object recognition,and movement of robot is controlled by angle of servo motor and distance of ultrasonic sensors.Not adopting the existing tracking methods:camera,laser-infrared(LRF)and many ultrasonic sensors,the proposed method proves that it is possible to track object using ultrasonic sensor and servo motor.Trajectory of robot is represented and analysed according to movement of object in limited conditions.
基金The National Natural Science Foundation of China(No.60575049)
文摘In this paper,three dimensions kinematics and kinetics simulation are discussed for hardware realization of a physical biped walking-chair robot.The direct and inverse close-form kinematics solution of the biped walking-chair robot is deduced.Several gaits are realized with the kinematics solution,including walking straight on level floor,going up stair,squatting down and standing up.Zero Moment Point(ZMP)equation is analyzed considering the movement of the crew.The simulated biped walking-chair robot is used for mechanical design,gaits development and validation before they are tested on real robot.
文摘Predicting the performance of intelligent multi-robot systems is advantageous because running physical experiments with teams of robots can be costly and time consuming. Controlling for every factor can be difficult in the presence of minor disparities (i.e. battery charge). Access to a variety of environmental configurations and hardware choices is prohibitive in many cases. With the eminent need for dependable robot controllers and algorithms, it is essential to understand when real robot performance can be accurately predicted. New prediction methods must account for the effects of digital and physical interaction between the robots that are more complex than just collision detection of 2D or physics-based 3D models. In this paper, we identify issues in predicting multi-robot performance and present examples of statistical and model-based simulation methods and their applicability to multi-robot systems. Even when sensor noise, latency and environmental configuration are modeled in some complexity, multi-robot systems interject interference and messaging latency, causing many prediction systems to fail to correlate to absolute or relative performance. We support this supposition by comparing results from 3D physics-based simulations to identical experiments with a physical robot team for a coverage task.
基金Supported by the National Natural Science Foundation of China(Grant Nos.51822502 and 91948202)the National Key Research and Development Program of China(No.2019YFB1309500)the“111 Project”(Grant No.B07018).
文摘Soft robots have become important members of the robot community with many potential applications owing to their unique flexibility and security embedded at the material level.An increasing number of researchers are interested in their designing,manufacturing,modeling,and control.However,the dynamic simulation of soft robots is difficult owing to their infinite degrees of freedom and nonlinear characteristics that are associated with soft materials and flexible geometric structures.In this study,a novel multi-flexible body dynamic modeling and simulation technique is introduced for soft robots.Various actuators for soft robots are modeled in a virtual environment,including soft cable-driven,spring actuation,and pneumatic driving.A pneumatic driving simulation was demonstrated by the bending modules with different materials.A cable-driven soft robot arm prototype and a cylindrical soft module actuated by shape memory alley springs inspired by an octopus were manufactured and used to validate the simulation model,and the experimental results demonstrated adequate accuracy.The proposed technique can be widely applied for the modeling and dynamic simulation of other soft robots,including hybrid actuated robots and rigid-flexible coupling robots.This study also provides a fundamental framework for simulating soft mobile robots and soft manipulators in contact with the environment.
基金This project is supported by National Hi-tech Research and Development Program of China(863 Program,No.2001AAA423300)Provincial Natural Science Foundation of Anhui,China(No.00043310)
文摘Robot＇s dynamic motion error and on-line compensation based on multi-axis force sensor are dealt with.It is revealed that the reasons of the error are formed and the relations of the error are delivered.A motion equation of robot＇s termination with the error is established,and then,an error matrix and an error compensation matrix of the motion equation are also defined.An on-line error＇s compensation method is put forward to decrease the displacement error,which is a degree of millimeter,shown by the result of simulation of PUMA562 robot.
文摘A mobile robot developed by Wuhan University for full-path hotline inspection on 220 kV transmission lines was presented. With 4 rotating joints and 2 translational ones, such robot is capable of traveling along non- obstaclestraight-line segment and surmounting straight-line segment obstacles as well as transferring between two spans automatically. Lagrange’s equations were utilized to derive dynamic equations of all the links, including items of inertia, coupling inertia, Coriolis acceleration, centripetal acceleration and gravity. And a dynamic response experiment on elemental motions of robot prototype’s travelling along non-obstacle straight-line segment and surmounting obstacles was performed on 220 kV 1∶1 simulative overhanging transmission-line in laboratory. In addition, dynamic numerical simulation was conducted in the corresponding condition. Comparison and analysis on results of experiment and numerical simulation have validated theoretical model and simulation resolution. Therefore, the dynamic model formed hereunder can be used for the study of robot control.
基金Natural Science Foundation of Tianjin(No.07JCYBJC04400).
文摘The motion simulation of arc welding robot is the basis of the system of robot off-line programming, and it has been one of the important research directions. The UGNX 4. 0 is adopted to establish 3D simulating model of MOTOMAN-HP6 arc welding robot. The kinematic model under link-pole coordinate system is established by the second development function offered by UG/OPEN API and the method of programming using VC ＋＋ 6. 0. The methods of founding model and operational procedures are introduced, which provides a good basis for off-line programming technique under Unigraphies condition.
基金This project is supported by Natonal Natural Science Foundation of China (No.50128504).
文摘When robot is at singular configuration, the limited hand velocity wouldrequire some joints with infeasible speeds so as to lead unsafely of the system. A method of solvingthe approximate velocity of joint near singular configuration point by adding damped vector isproposed and a modified algorithm is provided. With the analysis of J^(-1) the singularconfigurations of 6R robot are divided into structure boundary singularity , boundary singularity ,inner singularity and wrist singularity. The conditions of singularities of the robot have beenascertained. The computer simulations of the singularities of the robot are developed, which havemany advantages over previous description methods of the singular configurations of robot. With thehelp of boundary singularity analysis, a application in welding trajectory planning checking of therobot has been carried out and the simulation result proved visualized and useful.
基金Projects 2005AA133070 supported by the National High Technology Research and Development Program of China[2005]688 and [2005]555 by the Devel-opment Fund for Electronic and Information Industry
文摘In order to provide a theoretical basis for methane sensor placement in the vertical direction of a tunnel,the software Fluent was used to simulate methane distribution. A geometric roadway model was established and divided by grids. Methane distribution in both level and vertical sections was simulated using a realizable k-ε model with the Fluent software according to a conservation equation in a turbulent state,a turbulent kinetic energy equation and a turbulent dissipation rate equation. The realizable k-ε model and the Fluent software were used to simulate methane distribution according to the principle of the conservation equation in a state of turbulent flow. The results show that after overflow-ing,a methane level with a certain thickness is formed. Methane density curves at three specific levels were internally consistent and methane density at higher levels is denser than that at lower levels. Methane distribution becomes thinner in the direction of wind and methane in the vertical direction becomes uniform if wind speed is high. The distance be-tween sensors and roof should be less than 300 mm which is in agreement with mine safety regulations.
文摘In the underwater environment, many visual sensors don’t work, and many sensors which work well for robots working in space or on land can not be used underwater. Therefore, an optical fiber slide tactile sensor was designed based on the inner modulation mechanism of optical fibers. The principles and structure of the sensor are explained in detail. Its static and dynamic characteristics were analyzed theoretically and then simulated. A dynamic characteristic model was built and the simulation made using the GA based neural network. In order to improve sensor response, the recognition model of the sensor was designed based on the ‘inverse solution’ principle of neural networks, increasing the control precision and the sensitivity of the manipulator.
基金Project(60575053) supported by the National Natural Science Foundation of China
文摘In order to simulate the gait of human walking on different terrains a new robot with six degrees of freedom was proposed. Based on sand bearing characteristic compliance control was introduced to control system in horizontal and vertical movement directions at the end of the robot,and position control in attitude. With Matlab/Simulink toolbox,the system control models were established,and the bearing characteristics of rigid ground,hard sand,soft sand and softer sand were simulated. The results show that 0,0.62,0.89 and 1.12 mm are the maximal subsidences of the four kinds of ground along the positive direction of x-axis,respectively,and 0,-0.96,-1.99 and -3.00 mm are the maximal subsidences along the negative direction of x-axis,respectively. Every subsidence along y-axis is negative,and 0,-4.12,-8.23 and -12.01 mm are the maximal subsidences of the four kinds of ground,respectively. Simulation results show that the subsidence of footboard points to inferior anterior in early stage of stand phase,while points to posterior aspect in late stage. The subsidence tends to point to posterior aspect in the whole. These results are basically consistent with the gait characteristics of human walking on sand. Gait simulation of the robot for human walking on sand is achieved.
基金The National Natural Science Foundation of China(No.62173122)the Hebei Key Project of Natural Science Foundation(No.F2021201031)。
文摘A passive simulation method based on the six degrees of freedom(6-DOF)model and dynamic mesh is proposed according to the working principle to study the dynamic characteristics of the turbine flow sensors.This simulation method controls the six degrees of freedom of the impeller using the user-defined functions(UDF)program so that it can only rotate under the impact of fluid.The impeller speed can be calculated in real-time,and the inlet speed can be set with time to obtain the dynamic performance of the turbine flow sensors.Based on this simulation method,three turbine flow sensors with different diameters were simulated,and the reliability of the simulation method was verified by both steady-state and unsteady-state experiments.The results show that the trend of meter factor with flow rate acquired from the simulation is close to the experimental results.The deviation between the simulation and experiment results is low,with a maximum deviation of 2.88%.In the unsteady simulation study,the impeller speed changed with the inlet velocity of the turbine flow sensor,showing good tracking performance.The passive simulation method can be used to predict the dynamic performance of the turbine flow sensor.
文摘Because of the special underwater environment, many sensors used well in robots working in space or on the land can not be used in the underwater. So an optical fiber type slide tactile sensor is designed by the inner modulation mechanism of the intensity type optical fiber. The principle and structure of the sensor are introduced in detail. The static and dynamic characteristics are analyzed theoretically and experimentally. The dynamic characteristic model is built and the simulation is made by using genetic algorithm based on neural network. In order to use the sensor perfectly, the recognition model of the sensor is built on the basis of the principle of “inverse solution” using neural networks. The control precision and sensitivity of the manipulator are improved.
基金Project supported by the Natural Science Foundation of Heilongjiang ProvinceChina(Grant No.ZD2019H003)+4 种基金the Joint Research Fund in Astronomy under Cooperative Agreement Between the National Natural Science Foundation of China and Chinese Academy of Sciences(Grant Nos.U1631239 and U1931206)the 111 ProjectChina(Grant No.B13015)the Fundamental Research Funds for the Central Universities to the Harbin Engineering UniversityChina。
文摘The purpose of this article is to explore the cause of the over-response phenomenon of fiber x-ray sensor.The sensor is based on a length of PMMA fiber,whose end is filled with the scintillation material Gd_(2)O_(2)S:Tb.The Monte Carlo simulation software GEANT4 uses the phase space file provided by the International Atomic Energy Agency(IAEA),by irradiating the fiber x-ray sensor in the water phantom,counting the fluorescence signal of the optical fiber x-ray sensor after propagation through the fiber.In addition,the number of Cerenkov photons propagating through the fiber is also counted.Comparing this article with previous research,we believe that one of the reasons for the over-response of the fiber x-ray sensor is the non-linear response of the deposition energy of the scintillator to the fluorescence.By establishing a region of interest and counting the x-rays in this region,the simulation results show that the counted number of x-rays that may affect the fiber x-ray sensor is the biggest in the area of interest at a water depth of 5 cm.This result is close to the maximum dose point of the experimental and simulated percentage depth dose(PDD) curve of fiber x-ray sensor.Therefore,the second reason of the over-response phenomenon is believed to be fact that the inorganic materials such as Gd_(2)O_(2)S:Tb have larger effective atomic numbers,so the fiber x-ray sensors will cause more collisions with x-ray in a low energy region of 0.1 MeV-1.5 MeV.
文摘In order to observe the change and fluctuation in flow and pressure of a hydraulic quadruped robot＇s hydraulic system when the robot walks on trot gait,a co-simulation method based on ADAMS and AMESim is proposed. Firstly,the change rule in each swing angle of the hydraulic quadruped robot＇s four legs is analyzed and converted to the displacement change of the hydraulic cylinder by calculating their geometric relationship.Secondly,the robot＇s dynamic model is built in ADAMS and its hydraulic and control system models are built in AMESim. The displacement change of the hydraulic cylinder in the hydraulic system is used as the driving function of the dynamics model in ADAMS,and the driving force of the dynamics model is used as the loads of the hydraulic system in AMESim. By introducing the PID closed-loop control in the control system,the co-simulation between hydraulic system and mechanical system is implemented. Finally,the curve of hydraulic cylinders＇ loads,flow and pressure are analyzed and the results show that they fluctuate highly in accordance with the real situation. The study provides data support for the development of a hydraulic quadruped robot＇s physical prototype.
