In this paper, redundancy resolution of a cable-driven parallel manipulator is solved by an iterative-analytic scheme. The method can be applied to all kind of redundant manipulators either parallel or serial with con...
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In this paper, redundancy resolution of a cable-driven parallel manipulator is solved by an iterative-analytic scheme. The method can be applied to all kind of redundant manipulators either parallel or serial with constraint caused through their dynamics. However, for sake of simulation the proposed method is implemented on a cable-driven redundant parallel manipulator (CDRPM). The redundancy resolution problem is formulated as a convex optimization with equality and non-equality constraints caused by manipulator structure and cables dynamics. Karush-Kuhn-Tucker theorem is used to analyze the optimization problem and to find an analytic solution. Subsequently, a tractable and iterative search algorithm is proposed to solve the redundancy resolution of such redundant mechanisms. Furthermore, it is shown through the simulation that, the elapsed time required to implement the analytical redundancy resolution scheme in a closed-loop structure is considerably less than that of other numerical optimization methods.
A prototype concurrent engineering tool has been developed for the preliminary design of composite topside structures for modern navy warships. This tool, named GELS for the Concurrent engineering of Layered Structure...
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A prototype concurrent engineering tool has been developed for the preliminary design of composite topside structures for modern navy warships. This tool, named GELS for the Concurrent engineering of Layered Structures, provides designers with an immediate assessment of the impacts of their decisions on several disciplines which are important to the performance of a modern naval topside structure, including electromagnetic interference effects (EMI), radar cross section (RCS), structural integrity, cost, and weight. Preliminary analysis modules in each of these disciplines are integrated to operate from a common set of design variables and a common materials database. Performance in each discipline and an overall fitness function for the concept are then evaluated. A graphical user interface (GUI) is used to define requirements and to display the results from the technical analysis modules. Optimization techniques, including feasible sequential quadratic programming (FSQP) and exhaustive search are used to modify the design variables to satisfy all requirements simultaneously. The development of this tool, the technical modules, and their integration are discussed noting the decisions and compromises required to develop and integrate the modules into a prototype conceptual design tool.
The problem of classification can be stated as: "Given a set of a attributes and the characterization of n objects by means of a attribute values for each object, find an optimal classification (partition) of the...
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The problem of classification can be stated as: "Given a set of a attributes and the characterization of n objects by means of a attribute values for each object, find an optimal classification (partition) of the n objects into classes". The first step in supervised classification is to find k, the number of classes into which the objects have to be split in order to obtain the optimum classification. The dynamic kernels algorithm searches for a classification which maximizes B [=/spl Sigma//sub j=1//sup k/n/sub j/d(G/sub j/,G), where d(G/sub j/,G) denotes the distance between the points G/sub j/ and G, G is the center of gravity of the n given points and G/sub j/ are the centers of gravity of the k classes]. Unfortunately, the maximum value of B is not the same for different values of k, so the Huygens theorem can only be used for comparing classifications of the given objects into a fixed number of classes. We propose an evolution program for this problem. It simultaneously searches for both the optimum number of classes and the optimal classification. So far, we have implemented our approach for the case of two attributes with continuous values. Straightforward adaptations are under way for allowing the user to input any reasonable number of (continuous or discrete) attributes.< >
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