The paper presents a new algorithm for generating offset curve of two-dimensional contour that is combined of lines and circular arcs. In comparison with conventional Pairwise-intersection approach, the new algorithm needs less computation for offset curve generation and can generate the offset curve correctly for all possible cases. A cut-off machining, which can reduce non-productive preparatory operations before machining, is suggested for machining small size prismatic products. The offset curve generation algorithm proposed in this paper is applied to tool path generation in the cut-off machining. Based on the offset curve generation algorithm, an approach is presented for detecting uncut segments of two-dimensional contour in the cut-off machining.
This paper deals with a LQR problem for 2D (2-dimensional) systems in the case that one independent variable is bounded but the other is unbounded. First, we formulate the 2D LQR problem for Roesser model. Then it is shown that the problem can be reduced to an equivalent LQR problem for 1D systems, and thus, can be solved by 1D theory. The obtained controller has one direction causality. The relationship between the solvability conditions obtained for the equivalent 1D system and the practical stabilizability and detectability of the original 2D plant is clarified. Based on these results, its application to the design of an iterative learning control system is shown. Finally, a numerical example is also given to verify the effectiveness.
This paper proposes a method of ultra high-speed digital measurement and feedback control for treatment of the phenomenon that is moving or changing at near velocity of light. This method contains several important technologies for real-time processing and operations, those of high-speed random access control for memory system, high-speed parallel processing, high-speed input / output with high stability, means for keeping accuracy of the absolute time for control-interval and input/output timing, and so on. As one of the applications of ultra high-speed digital feed-back system, we tried to apply our method to the feed-back control system to control many bunches with large amount of electrons and positrons turning at near velocity of light in the inside of a colliding type accelerator consisting of two rings, one for electrons and one for positrons, crossing each other, and attempted a development of prototype system for said application and several kind of experiments to evaluate its performances. From results of the attempts, a prospect of realizing the application and a recognition of availabilities of our method have been obtained.
A comparison theorem for the solutions of two generalized algebraic Riccati equations (GAREs) coming from two different systems is presented in this paper. It is then shown that the so-called strong solutions, whose related pencils have all their finite eigenvalues in the closed left half plane, are maximal. The results obtained in this paper generalize the existing monotonicity results of algebraic Riccati equations. An application of the results is the derivation of the parameterization of all strong solutions of the GARE related to the singular spectral factorization of a proper transfer function with finite and infinite imaginary axis zeros.
This paper presents an optimization methodology for operating schedule of DHC (district heating and cooling) plants. The optimization models are constructed by input-output properties of the components into a mixed 0-1 linear programming problem. The advanced features of the method are dealing with 1) double-bundle heat pumps, 2) thermal storage tanks, and 3) peak-cut strategy. The computer simulation shows that the optimization results based on the method are an appropriate schedule for the DHC plant operation.
In our previous work we have developed fuzzy classifiers with ellipsoidal regions and with hyperbox regions. In this paper we discuss linear transformation invariance of these classifiers. First, we prove that the fuzzy classifier with ellipsoidal regions, which is based on the Mahalanobis distance, has invariance for linear transformation of input variables. Then we prove that the fuzzy classifier with hyperbox regions, whose surfaces are parallel to input axes, has limited scale invariance. Finally, we show the advantages of our classifiers over neural networks by the performance evaluation of benchmark data.
The feedback control of attitude changes for a spacecraft with two reaction wheels is considered. Rodriguez parameters are used for attitude expression, and the system is expressed in a simple non-holonomic form. Then a continuous feedback law is proposed for the three-axis control of spacecraft attitude. The stability of the closed-loop system is examined by an equivalent linearized system. The validity of the control law is verified by numerical simulations.