A mechanical system, such as a robot system for man-robot cooperation, a master-slave manipulator system, a power-steering system, an extender etc. has interactions among the system, the operator and its environment. ...
详细信息
ISBN:
(纸本)0780307534
A mechanical system, such as a robot system for man-robot cooperation, a master-slave manipulator system, a power-steering system, an extender etc. has interactions among the system, the operator and its environment. How to control the interactions so that the desired interaction is realized, is one of the key issues for the control of such a mechanical system. The design of the controller of mechanical systems with man-machine interactions is discussed. The authors first model the mechanical system, which has interactions with its environment and an operator, then propose a control algorithm so that the desired interaction is realized. The proposed control system, consists of two controllers: one generates the desired motion of the mechanical system based on the force applied to the system, and the other one controls the interaction between the system and its environment. The proposed control algorithm specifies both force augmentation and maneuverability of the system. The algorithm is applied to a planar manipulator with one degree of freedom and the experimental system illustrates the concept of the system.
We investigate numerically totalistic cellular automata rules in four and five dimensions that have been recently proposed by Chaté and Manneville and that show periodic or quasiperiodic time sequences in the mag...
详细信息
We investigate numerically totalistic cellular automata rules in four and five dimensions that have been recently proposed by Chaté and Manneville and that show periodic or quasiperiodic time sequences in the magnetization. We show how to implement such rules fast on a Connection Machine. We confirm the proposed behavior by analyzing the time and size dependence of the distance from the attractor. Also the dependence of the initial configuration, the behavior of very small systems and mean-field calculations are presented.
Dynamic channel allocation can reduce the probability of blocking of cellular telephone networks. However, more is needed to achieve optimal performance. This paper aims at estimating the minimal blocking probability ...
详细信息
Dynamic channel allocation can reduce the probability of blocking of cellular telephone networks. However, more is needed to achieve optimal performance. This paper aims at estimating the minimal blocking probability for some simple cellular networks. Its contribution is three-fold: some dynamic channel allocation strategies are analyzed, the optimal performance (obtained by dynamic allocation and flow control) of some very simple networks is computed, simple bounds on optimal performance are presented. These results lead to a better understanding of cellular networks and can serve to evaluate new control algorithms.
There exist useful paradigms for establishing global convergence of adaptive controllers for linear, discrete-time, deterministic, and stochastic systems and linear continuous-time deterministic systems. More recently...
详细信息
There exist useful paradigms for establishing global convergence of adaptive controllers for linear, discrete-time, deterministic, and stochastic systems and linear continuous-time deterministic systems. More recently, global convergence of an indirect adaptive controller for continuous-time stochastic linear systems has been established. This paper completes this program by establishing global convergence and asymptotic properties of a direct adaptive controller for continuous-time stochastic linear systems. This result is comprehensive and covers many other existing results as special cases. It also has practical implications for the discrete-time case since it reveals how the existing discrete-time results must be modified so that they have meaningful limits as the sampling period decreases.
The visual information obtained from a camera and an image processing unit is incorporated in an adaptive control algorithm to make a robotic manipulator grasp a moving object. Because of the inherent time delay cause...
详细信息
The visual information obtained from a camera and an image processing unit is incorporated in an adaptive control algorithm to make a robotic manipulator grasp a moving object. Because of the inherent time delay caused by the image processing, the motion of the moving target is predicted in real-time and is used in the on-line planning of the trajectory for the manipulator motion. Since the dynamics of the target are assumed to be unknown, the prediction is accomplished by means of an auto-regressive (AR) discrete-time model. On the basis of the predicted motion of the object, the planner determines on-line at each control sampling instant the desired trajectory point (subgoal) for the controller. The subgoal point is tracked by controlling the end-effector with self-tuner until grasping occurs. A simulation study and laboratory experiments are presented to demonstrate the performance of this visual feedback system.
A thorough analysis of a new scalar control method for the operation of direct frequency changers using bidirectional switches operating at high switching frequencies is proposed. The method uses the instantaneous vol...
详细信息
A thorough analysis of a new scalar control method for the operation of direct frequency changers using bidirectional switches operating at high switching frequencies is proposed. The method uses the instantaneous voltage ratio of specific input phase voltages to generate the active and zero states of the various switches. A voltage transfer ratio as high as 0.87 is obtained under synchronous and asynchronous operation with a conventionally connected three phase load. Moreover, the converter operation can be set to produce almost any power displacement factor, independent of load power factor.
This note presents the proof for the exponential convergence of a class of learning and repetitive control algorithms for robot manipulators. The learning process involves the identification of the robot inverse dynam...
详细信息
This note presents the proof for the exponential convergence of a class of learning and repetitive control algorithms for robot manipulators. The learning process involves the identification of the robot inverse dynamics function by having the robot execute a set of tasks repeatedly. Using the concepts of functional persistence of excitation (PE) and functional uniform complete observability (UCO), it is shown that, when a training task is selected for the robot which is persistently exciting, the learning controllers are globally exponentially stable. Repetitive controllers are always exponentially stable.
A new method for large-scale numerical simulations of neural networks is proposed which reduces the computational effort by incrementally updating the local fields and thus restricting the operations to flipped spins ...
详细信息
A new method for large-scale numerical simulations of neural networks is proposed which reduces the computational effort by incrementally updating the local fields and thus restricting the operations to flipped spins only. A highly optimized multi-spin algorithm is described employing words oriented along the columns of the coupling matrix unlike the horizontal structure in existing high-speed algorithms. An effective rate of 35+109 couplings/s on a Cray-YMP can be attained which is about five times as fast as best existing multi-spin implementations.
暂无评论