The kinematics of robots mainly analyses the transformational relation between links and the end-actuator position and orientation of robots,its two kinds of topics mainly include:direct kinematics topic and inverse k...The kinematics of robots mainly analyses the transformational relation between links and the end-actuator position and orientation of robots,its two kinds of topics mainly include:direct kinematics topic and inverse kinematics topic[1].This paper mainly researched the inverse kinematics of Six-DOF robots,built Six-DOF robots inverse kinematics model with D-H parameter model,and worked out the robot’s homogeneous transformation matrix[2].Now we will build the model and study to the inverse kinematics of RBT-6SO3S which from Jiang Su Hui-Bo Robots Company.展开更多
Real-time modeling and simulation of flight system are the key parts of simulator. After describing the architecture of simulator for a newer fighter, author presents the composition of flight system and its mathemati...Real-time modeling and simulation of flight system are the key parts of simulator. After describing the architecture of simulator for a newer fighter, author presents the composition of flight system and its mathematic models. In this paper, aircraft is regarded as an elastic flight body. And a new integrated algorithm which can remedy the shortcoming of Euler method and four-element method is used to calculate the Eulerian angles of aircraft. Finally, the software implementation of the flight system is given in the paper.展开更多
An improved STT (skid to turn) autopilot was developed to solve the problem of roll control saturation for the gliding missile with large aspect ratio. A lateral acceleration feedback was introduced in the roll channe...An improved STT (skid to turn) autopilot was developed to solve the problem of roll control saturation for the gliding missile with large aspect ratio. A lateral acceleration feedback was introduced in the roll channel of the autopilot to ensure that the roll angle could closely follow the lateral acceleration,so that the sideslip angle and the roll rudder deflection could be reduced,and the roll control saturation was avoided. A six-DOF ( degree of freedom) nonlinear simulation model was set up. The simulation results indicate that the model and the control scheme are effective.展开更多
We report a method for simultaneously and directly measuring all six-degrees-of-freedom(six-DOF) motion errors of a rotary axis. Such a method combines the principles of laser interferometry and laser collimation meas...We report a method for simultaneously and directly measuring all six-degrees-of-freedom(six-DOF) motion errors of a rotary axis. Such a method combines the principles of laser interferometry and laser collimation measurement. One reference rotary axis and two retro-reflectors are used to achieve simultaneous sensitivity to all six errors in a full-circle measuring range. As no separation models are required, our method is capable of dynamically measuring these errors in real time and conveniently determining the origin of the errors. An automatic measuring device is built. The effectiveness of our method is experimentally demonstrated.展开更多
Free-moving simulations of airplanes, submarines and other automobiles under extreme and emergency conditions are becoming increasingly important from operational and tactical perspectives. Such simulations are fairly...Free-moving simulations of airplanes, submarines and other automobiles under extreme and emergency conditions are becoming increasingly important from operational and tactical perspectives. Such simulations are fairly challenging due to the extreme unsteady motions and high Re(Reynolds) numbers. The aim of this study is to perform a six-DOF motion simulation of a 6:1prolate spheroid that is falling in a fluid field. Prior to conducting the six-DOF simulation, some verification simulations were performed. First, a laminar flow past an inclined prolate spheroid at a Re number of 1000 and incidence angle of 45. with a tetrahedral mesh was simulated to verify the relevant targeted discrete method for an unstructured mesh. Second, to verify the LES(large eddy simulation) models and dependent parameters for the DDES(delayed detached eddy simulation), a turbulent flow past a sphere was performed at a subcritical Re number of 10000. Third, a steady maneuvering problem about a prolate spheroid pitching up from 0. to 30. incidence at a uniform angular velocity was established based on a dynamic tetrahedral mesh with changing topology and the ALE(arbitrary Lagrangian-Eulerian) method of fluid-structure coupling at a Re number of 4.2 × 10~6.Finally, two six-DOF motions of an inclined 6:1 prolate spheroid at an initial incidence of 45. were simulated at different Re numbers of 10000 and 4.2 × 10~6.展开更多
文摘The kinematics of robots mainly analyses the transformational relation between links and the end-actuator position and orientation of robots,its two kinds of topics mainly include:direct kinematics topic and inverse kinematics topic[1].This paper mainly researched the inverse kinematics of Six-DOF robots,built Six-DOF robots inverse kinematics model with D-H parameter model,and worked out the robot’s homogeneous transformation matrix[2].Now we will build the model and study to the inverse kinematics of RBT-6SO3S which from Jiang Su Hui-Bo Robots Company.
文摘Real-time modeling and simulation of flight system are the key parts of simulator. After describing the architecture of simulator for a newer fighter, author presents the composition of flight system and its mathematic models. In this paper, aircraft is regarded as an elastic flight body. And a new integrated algorithm which can remedy the shortcoming of Euler method and four-element method is used to calculate the Eulerian angles of aircraft. Finally, the software implementation of the flight system is given in the paper.
文摘An improved STT (skid to turn) autopilot was developed to solve the problem of roll control saturation for the gliding missile with large aspect ratio. A lateral acceleration feedback was introduced in the roll channel of the autopilot to ensure that the roll angle could closely follow the lateral acceleration,so that the sideslip angle and the roll rudder deflection could be reduced,and the roll control saturation was avoided. A six-DOF ( degree of freedom) nonlinear simulation model was set up. The simulation results indicate that the model and the control scheme are effective.
基金supported by the National Natural Science Foundation of China(No.51527806)the Fundamental Research Funds for the Central Universities(No.2016RC019)
文摘We report a method for simultaneously and directly measuring all six-degrees-of-freedom(six-DOF) motion errors of a rotary axis. Such a method combines the principles of laser interferometry and laser collimation measurement. One reference rotary axis and two retro-reflectors are used to achieve simultaneous sensitivity to all six errors in a full-circle measuring range. As no separation models are required, our method is capable of dynamically measuring these errors in real time and conveniently determining the origin of the errors. An automatic measuring device is built. The effectiveness of our method is experimentally demonstrated.
基金supported by the National Natural Science Founation of China(Grant No.11572350)
文摘Free-moving simulations of airplanes, submarines and other automobiles under extreme and emergency conditions are becoming increasingly important from operational and tactical perspectives. Such simulations are fairly challenging due to the extreme unsteady motions and high Re(Reynolds) numbers. The aim of this study is to perform a six-DOF motion simulation of a 6:1prolate spheroid that is falling in a fluid field. Prior to conducting the six-DOF simulation, some verification simulations were performed. First, a laminar flow past an inclined prolate spheroid at a Re number of 1000 and incidence angle of 45. with a tetrahedral mesh was simulated to verify the relevant targeted discrete method for an unstructured mesh. Second, to verify the LES(large eddy simulation) models and dependent parameters for the DDES(delayed detached eddy simulation), a turbulent flow past a sphere was performed at a subcritical Re number of 10000. Third, a steady maneuvering problem about a prolate spheroid pitching up from 0. to 30. incidence at a uniform angular velocity was established based on a dynamic tetrahedral mesh with changing topology and the ALE(arbitrary Lagrangian-Eulerian) method of fluid-structure coupling at a Re number of 4.2 × 10~6.Finally, two six-DOF motions of an inclined 6:1 prolate spheroid at an initial incidence of 45. were simulated at different Re numbers of 10000 and 4.2 × 10~6.
