In order to improve the trajectory tracking precision and reduce the synchronization error of a 6-DOF lightweight robot, nonlinear proportion-deviation (N-PD) cross-coupling synchronization control strategy based on...In order to improve the trajectory tracking precision and reduce the synchronization error of a 6-DOF lightweight robot, nonlinear proportion-deviation (N-PD) cross-coupling synchronization control strategy based on adjacent coupling error analysis is presented. The mathematical models of the robot, including kinematic model, dynamic model and spline trajectory planing, are established and verified. Since it is difficult to describe the real-time contour error of the robot for complex trajectory, the adjacent coupling error is analyzed to solve the problem. Combined with nonlinear control and coupling performance of the robot, N-PD cross-coupling synchronization controller is designed and validated by simulation analysis. A servo control experimental system which mainly consists of laser tracking system, the robot mechanical system and EtherCAT based servo control system is constructed. The synchronization error is significantly decreased and the maximum trajectory error is reduced from 0.33 mm to 0.1 mm. The effectiveness of the control algorithm is validated by the experimental results, thus the control strategy can improve the robot's trajectory tracking precision significantly.展开更多
To design a hyperchaotic generator and apply chaos into secure communication, a linear unidirectional coupling control is applied to two identical simplified Lorenz systems. The dynamical evolution process of the coup...To design a hyperchaotic generator and apply chaos into secure communication, a linear unidirectional coupling control is applied to two identical simplified Lorenz systems. The dynamical evolution process of the coupled system is investigated with variations of the system parameter and coupling coefficients. Particularly, the influence of coupling strength on dynamics of the coupled system is analyzed in detail. The range of the coupling strength in which the coupled system can generate hyperchaos or realize synchronization is determined, including phase portraits, Lyapunov exponents, and Poincare section. And the critical value of the system parameter between hyperchaos and synchronization is also found with fixed coupled strength. In addition, abundant dynamical behaviors such as four-wing hyperchaotic, two-wing chaotic, single-wing coexisting attractors and periodic orbits are observed and chaos synchronization error curves are also drawn by varying system parameter c. Numerical simulations are implemented to verify the results of these investigations.展开更多
为实现多轴伺服驱动压力机的同步控制,文章基于传统偏差耦合控制提出一种虚拟轴改进型偏差耦合同步控制方法,并搭建同步控制实验平台进行现场验证。基于压力机结构和控制模型实现模糊比例积分微分(proportional integral derivative,PID...为实现多轴伺服驱动压力机的同步控制,文章基于传统偏差耦合控制提出一种虚拟轴改进型偏差耦合同步控制方法,并搭建同步控制实验平台进行现场验证。基于压力机结构和控制模型实现模糊比例积分微分(proportional integral derivative,PID)位置跟踪控制;在传统偏差耦合控制结构中添加评价误差模块,搭建一种改进型偏差耦合同步控制方法,提高同步系统的抗扰动能力和同步精度;将虚拟轴引入改进型偏差耦合控制结构中,从而解除多轴间的直接耦合关系,简化改进型同步位移补偿结构。实验结果表明,该方法有效提高了压力机同步抗扰动能力和稳态同步精度。展开更多
大型同步调相机配套管道异常振动问题,不仅会降低管道的使用寿命,还会影响调相机润滑油和冷却液的供应,严重时甚至会造成重大安全事故,危害电力系统的稳定性。以某特高压换流站的同步调相机润滑油供油管道为研究对象,使用现场测量、流...大型同步调相机配套管道异常振动问题,不仅会降低管道的使用寿命,还会影响调相机润滑油和冷却液的供应,严重时甚至会造成重大安全事故,危害电力系统的稳定性。以某特高压换流站的同步调相机润滑油供油管道为研究对象,使用现场测量、流固耦合和谐响应分析等多种方法,研究了管道振动的产生原因和机制。结果表明,由调相机本身产生的周期性激振力是管道振动的主要原因。进一步提出基于调谐质量阻尼器(Tuned Mass Damper,TMD)的管道减振措施,试验和仿真数据表明,在润滑油供油管道系统4和5、6和7支吊架中间位置各安装一个TMD,减振效果最佳,可将该管系的振动加速度降低90%以上,具有良好的减振效果。展开更多
基金Project(2015AA043003)supported by National High-technology Research and Development Program of ChinaProject(GY2016ZB0068)supported by Application Technology Research and Development Program of Heilongjiang Province,ChinaProject(SKLR201301A03)supported by Self-planned Task of State Key Laboratory of Robotics and System(Harbin Institute of Technology),China
文摘In order to improve the trajectory tracking precision and reduce the synchronization error of a 6-DOF lightweight robot, nonlinear proportion-deviation (N-PD) cross-coupling synchronization control strategy based on adjacent coupling error analysis is presented. The mathematical models of the robot, including kinematic model, dynamic model and spline trajectory planing, are established and verified. Since it is difficult to describe the real-time contour error of the robot for complex trajectory, the adjacent coupling error is analyzed to solve the problem. Combined with nonlinear control and coupling performance of the robot, N-PD cross-coupling synchronization controller is designed and validated by simulation analysis. A servo control experimental system which mainly consists of laser tracking system, the robot mechanical system and EtherCAT based servo control system is constructed. The synchronization error is significantly decreased and the maximum trajectory error is reduced from 0.33 mm to 0.1 mm. The effectiveness of the control algorithm is validated by the experimental results, thus the control strategy can improve the robot's trajectory tracking precision significantly.
基金Supported by National Natural Science Foundation of China(60474029 60774045 60634020 61075065) the Graduate Degree Thesis Innovation Foundation of Central South University
基金Projects(61073187,61161006) supported by the National Nature Science Foundation of ChinaProject supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry,China
文摘To design a hyperchaotic generator and apply chaos into secure communication, a linear unidirectional coupling control is applied to two identical simplified Lorenz systems. The dynamical evolution process of the coupled system is investigated with variations of the system parameter and coupling coefficients. Particularly, the influence of coupling strength on dynamics of the coupled system is analyzed in detail. The range of the coupling strength in which the coupled system can generate hyperchaos or realize synchronization is determined, including phase portraits, Lyapunov exponents, and Poincare section. And the critical value of the system parameter between hyperchaos and synchronization is also found with fixed coupled strength. In addition, abundant dynamical behaviors such as four-wing hyperchaotic, two-wing chaotic, single-wing coexisting attractors and periodic orbits are observed and chaos synchronization error curves are also drawn by varying system parameter c. Numerical simulations are implemented to verify the results of these investigations.
文摘为实现多轴伺服驱动压力机的同步控制,文章基于传统偏差耦合控制提出一种虚拟轴改进型偏差耦合同步控制方法,并搭建同步控制实验平台进行现场验证。基于压力机结构和控制模型实现模糊比例积分微分(proportional integral derivative,PID)位置跟踪控制;在传统偏差耦合控制结构中添加评价误差模块,搭建一种改进型偏差耦合同步控制方法,提高同步系统的抗扰动能力和同步精度;将虚拟轴引入改进型偏差耦合控制结构中,从而解除多轴间的直接耦合关系,简化改进型同步位移补偿结构。实验结果表明,该方法有效提高了压力机同步抗扰动能力和稳态同步精度。
文摘大型同步调相机配套管道异常振动问题,不仅会降低管道的使用寿命,还会影响调相机润滑油和冷却液的供应,严重时甚至会造成重大安全事故,危害电力系统的稳定性。以某特高压换流站的同步调相机润滑油供油管道为研究对象,使用现场测量、流固耦合和谐响应分析等多种方法,研究了管道振动的产生原因和机制。结果表明,由调相机本身产生的周期性激振力是管道振动的主要原因。进一步提出基于调谐质量阻尼器(Tuned Mass Damper,TMD)的管道减振措施,试验和仿真数据表明,在润滑油供油管道系统4和5、6和7支吊架中间位置各安装一个TMD,减振效果最佳,可将该管系的振动加速度降低90%以上,具有良好的减振效果。