It is crucial for implementing force/position control of robotic manipulator under the constraint of unknown environment to determine the force control and the position control directions. This paper presents an on l...It is crucial for implementing force/position control of robotic manipulator under the constraint of unknown environment to determine the force control and the position control directions. This paper presents an on line algorithm to real timely estimate the tangent and the normal vectors of the constraint surface based on the measured contact force under the consideration of frictional force. A fuzzy synthesis policy is proposed to coordinate the conflict between the compliant force control and the stiff position control. An experimental study on an AdeptThree, a SCARA type robotic manipulator, is conducted. The experimental results show that the policy presented in the paper is effective.展开更多
Collision avoidance is always difficult in the planning path for a mobile robot. In this paper, the virtual force field between a mobile robot and an obstacle is formed and regulated to maintain a desired distance by ...Collision avoidance is always difficult in the planning path for a mobile robot. In this paper, the virtual force field between a mobile robot and an obstacle is formed and regulated to maintain a desired distance by hybrid force control algorithm. Since uncertainties from robot dynamics and obstacle degrade the performance of a collision avoidance task, intelligent control is used to compensate for the uncertainties. A radial basis function （RBF） neural network is used to regulate the force field of an accurate distance between a robot and an obstacle in this paper and then simulation studies are conducted to confirm that the proposed algorithm is effective.展开更多
如何快速地对永磁同步电机(permanent magnetic synchronous machine,PMSM)转子位置实现精确估计是实现PMSM无传感器控制的关键。然而,PMSM驱动系统的反电势谐波问题及其参数时变的特点影响基于锁相环(phase locked loop,PLL)转子位置...如何快速地对永磁同步电机(permanent magnetic synchronous machine,PMSM)转子位置实现精确估计是实现PMSM无传感器控制的关键。然而,PMSM驱动系统的反电势谐波问题及其参数时变的特点影响基于锁相环(phase locked loop,PLL)转子位置估计方法的速度和精度。由于PMSM定子反电势中包含大量谐波,已有基于锁相环的滤波方法无法根据转速变化自适应调节频率,导致变转速工况下转子位置估计精度降低。为此,提出一种基于自适应混合滤波器的PLL估计方法,在分析PMSM包含的反电势谐波成分后,设计一种调节参数的混合自适应滤波器(hybrid adaptive filter based PLL,HAF-PLL)。通过仿真实验验证了所提方法对反电势谐波具有良好的滤波效果,能够准确检测出PMSM的转子位置。展开更多
In order to meet the requirements of on-orbit servicing outside the cabin, a flexible, dexterous hand with easy grasping ability and strong loading capacity is designed. The dexterous hand is comprised of three finger...In order to meet the requirements of on-orbit servicing outside the cabin, a flexible, dexterous hand with easy grasping ability and strong loading capacity is designed. The dexterous hand is comprised of three fingers. Each finger is driven by a set of four linkages. Furthermore, two fingers have a set of axial rotational degrees of freedom. In order to achieve the position control and keep griping stability, the dexterous hand adopts a mechanism of hybrid force/position control. In the end, experimental results demonstrates that the on-orbit servicing dexterous hand has great adaptability and operational capability.展开更多
Antarctic scientific expedition has important strategic significance. It is an inevitable trend to apply robots to assist researchers during the Antarctic expedition. However, the robot manipula- tors at present have ...Antarctic scientific expedition has important strategic significance. It is an inevitable trend to apply robots to assist researchers during the Antarctic expedition. However, the robot manipula- tors at present have a series of problems and unable to meet the requirements of the Antarctic expe- dition. In this paper, a novel Antarctic modular robot manipulator is proposed, which has a compact structure with modular joints. The robot manipulator has high reliability, and quick assembling-and- disassembling ability. Through well wires arranging and thermal controlling, the manipulator can better adapt to the Antarctic environment. In addition, the work space of the manipulator is serious- ly analyzed, and a new hybrid position/force control method is adopted to make the manipulator per- form better. Simulation results validate the control method and show that the robot manipulator has a good performance to meet the requirements of Antarctic expedition.展开更多
文摘It is crucial for implementing force/position control of robotic manipulator under the constraint of unknown environment to determine the force control and the position control directions. This paper presents an on line algorithm to real timely estimate the tangent and the normal vectors of the constraint surface based on the measured contact force under the consideration of frictional force. A fuzzy synthesis policy is proposed to coordinate the conflict between the compliant force control and the stiff position control. An experimental study on an AdeptThree, a SCARA type robotic manipulator, is conducted. The experimental results show that the policy presented in the paper is effective.
基金Project supported by the Science and Technology Stress Projects of Hebei Province, China (Grant No 07213526)
文摘Collision avoidance is always difficult in the planning path for a mobile robot. In this paper, the virtual force field between a mobile robot and an obstacle is formed and regulated to maintain a desired distance by hybrid force control algorithm. Since uncertainties from robot dynamics and obstacle degrade the performance of a collision avoidance task, intelligent control is used to compensate for the uncertainties. A radial basis function （RBF） neural network is used to regulate the force field of an accurate distance between a robot and an obstacle in this paper and then simulation studies are conducted to confirm that the proposed algorithm is effective.
文摘如何快速地对永磁同步电机(permanent magnetic synchronous machine,PMSM)转子位置实现精确估计是实现PMSM无传感器控制的关键。然而,PMSM驱动系统的反电势谐波问题及其参数时变的特点影响基于锁相环(phase locked loop,PLL)转子位置估计方法的速度和精度。由于PMSM定子反电势中包含大量谐波,已有基于锁相环的滤波方法无法根据转速变化自适应调节频率,导致变转速工况下转子位置估计精度降低。为此,提出一种基于自适应混合滤波器的PLL估计方法,在分析PMSM包含的反电势谐波成分后,设计一种调节参数的混合自适应滤波器(hybrid adaptive filter based PLL,HAF-PLL)。通过仿真实验验证了所提方法对反电势谐波具有良好的滤波效果,能够准确检测出PMSM的转子位置。
基金Supported by the National Natural Science Foundation of China(61733001,61573063,61503029,U1713215)
文摘In order to meet the requirements of on-orbit servicing outside the cabin, a flexible, dexterous hand with easy grasping ability and strong loading capacity is designed. The dexterous hand is comprised of three fingers. Each finger is driven by a set of four linkages. Furthermore, two fingers have a set of axial rotational degrees of freedom. In order to achieve the position control and keep griping stability, the dexterous hand adopts a mechanism of hybrid force/position control. In the end, experimental results demonstrates that the on-orbit servicing dexterous hand has great adaptability and operational capability.
基金Supported by Beijing Science Foundation(4122065)National High Technology Research and Development Program of China("863" Program)(2011AA040202)National Science Foundation for Distinguished Young Scholar(60925014)
文摘Antarctic scientific expedition has important strategic significance. It is an inevitable trend to apply robots to assist researchers during the Antarctic expedition. However, the robot manipula- tors at present have a series of problems and unable to meet the requirements of the Antarctic expe- dition. In this paper, a novel Antarctic modular robot manipulator is proposed, which has a compact structure with modular joints. The robot manipulator has high reliability, and quick assembling-and- disassembling ability. Through well wires arranging and thermal controlling, the manipulator can better adapt to the Antarctic environment. In addition, the work space of the manipulator is serious- ly analyzed, and a new hybrid position/force control method is adopted to make the manipulator per- form better. Simulation results validate the control method and show that the robot manipulator has a good performance to meet the requirements of Antarctic expedition.
