In this study, two support tools are developed for construction of a dynamic simulation program for engineering systems (especially nuclear systems) by combining software modules. These are (1) a sub-system to support the module selection suitable for dynamic simulation and (2) a graphical user interface to support visual construction of simulation programs. The support tools are designed to be independent on the conception of software modules (data communication methods between modules). In the module selection sub-system of item 1, a module is characterized beforehand by keywords for several criteria. The similarity between the characteristic of requested module by users and that of registered modules in the module library is estimated by a weighted average of similarity indexes for criteria. In the module selection sub-system, the weights are flexibly extracted from users by applying the analytic hierarchy process. The graphical user interface helps users to specify both calling order of modules and data transfer between two modules. The availability of the support tools is evaluated by several sample problems of module selection and dynamic simulation model construction. The support tools will be a strong tool for the efficient usage of software modules.
It is important to verify the effectiveness of various control design methods by experiment. For this purpose, first, this paper proposes a new type of parallel inverted pendulum system for experimental use, whose controllability can be easily changed. Second, we analyze how the system characteristics depends on its physical parameters from the viewpoint of robust stability and controllability. Third, a two-degree-of-freedom controller is designed for the system based on the H∞ loop shaping design procedure. Finally, we evaluate the effectiveness of the controller by experiments, which includes the comparison with LQ optimal control method.
A trend towards improving automobile usage from safety, economic, efficiency and convenience points of view has actively come about. One of these trends involves the usage of computerized road net works. As a part of this study, we have studied investigation of round trip routes for supporting transportation systems. This paper has proposed a practical algorithm that finds the shortest round trip tour rounding arbitrary plural nodes on digital road maps. This method is based on our intuition. When we look at the road map and decide the shortest round trip routes, we should imagine a frame including all tour nodes. The frame is composed of a convex hull. The accuracy of the proposed algorithm and that of the former method is compared on the digital road maps. The time complexity of above algorithms are compared, also. From these results, it is shown that the proposed algorithm is effective for the round trip routes algorithm.
The machining process can be considered as a planned interaction of the workpiece and the cutting tool. In an unmanned manufacturing system, the results of this interaction are to be continuously monitored so that any changes in the machining environment can be sensed for corrective actions. In order to design the adaptive control for the turning operation, the adaptive control optimization and the process monitoring system for chip form identification, chatter vibration detection and built-up edge detection are proposed. Acoustic emission and force sensors are applied to identify the cutting state. The necessary action is provided by a decision table which has been derived from a number of experimental results. Several cutting tests have proved the validity of the proposed system in monitoring, controlling and optimizing the cutting process.
A concept of machining features of 3D free surfaces for process planning of removal operation is proposed. A modeling method for the removal form model defined by considering the concavity as machining features is suggested. In the removal form model, areas are classified and characterized by geometric shape and machining conditions. The proposed judgement method and algorithm for each area are explained concretely, and the effectiveness of them is also shown by examples. The connection relationships between each area are represented as graphs. Information on process planning is obtained from the graphs.