OBF (Orthonormal Basis Function) Fuzzy models have shown to be a promising approach to the areas of nonlinear system identification and control since they exhibit several advantages over those dynamic model topologies...
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ISBN:
(纸本)9780769531960
OBF (Orthonormal Basis Function) Fuzzy models have shown to be a promising approach to the areas of nonlinear system identification and control since they exhibit several advantages over those dynamic model topologies usually adopted in the literature. Although encouraging application results have been obtained, no automatic procedure had yet been developed to optimize the design parameters of these models. This paper elaborates on the use of a genetic algorithm (GA) especially designed for this task, in which a fitness function based on the Akaike information criterion plays a key role by considering both model accuracy and parsimony aspects. The use of linear (actually affine) and nonlinear local models is also investigated. The proposed methodology is evaluated in the modeling of a real nonlinear magnetic levitation system.
This paper proposes the walking pattern generation method, the kinematic resolution method of CoM (center of mass) Jacobian with an embedded motion, and the walking controller design method for humanoid robots. First,...
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This paper proposes the walking pattern generation method, the kinematic resolution method of CoM (center of mass) Jacobian with an embedded motion, and the walking controller design method for humanoid robots. First, the walking pattern is generated using the simplified model for bipedal robot. Second, the kinematic resolution of CoM Jacobian with embedded motion makes a humanoid robot balanced automatically during the movement of the all other limbs. Actually, it offers the ability of whole body coordination to the humanoid robot. Third, the walking controller is composed of the CoM controller minus the ZMP (zero momentum position) controller. Also, we show that the proposed walking controller brings the disturbance input-to-state stability (ISS) for the simplified bipedal walking robot model. Finally, the effectiveness of the proposed kinematic resolution method and walking controller is shown through experiments in regard to humanoid robot dancing and walking
This paper presents an intuitive approach to precise solid modelling in virtual reality environments. A hierarchically structured model is established to handle the tasks of object definition, object creation, and obj...
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This paper presents an intuitive approach to precise solid modelling in virtual reality environments. A hierarchically structured model is established to handle the tasks of object definition, object creation, and object rendering with an integrated data structure. Constraints are organized at different levels on different objects and are embedded in the data structure. A constraint reasoning engine is developed to automatically determine allowable motions for precise manipulation of virtual objects with online assistance from constraints. Examples are presented to demonstrate the advantage of precise solid modelling through constraint-based manipulations in virtual environments.
This paper investigates a novel approach for partitional clustering of a large collection of text documents by using an improved version of the classical differential algorithm (DE). Fast and accurate clustering of do...
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This paper investigates a novel approach for partitional clustering of a large collection of text documents by using an improved version of the classical differential algorithm (DE). Fast and accurate clustering of documents plays an important role in the field of text mining and automatic information retrieval systems. The k-means has served as the most widely used partitional clustering algorithm for text documents. However, in most cases it provides only locally optimal solutions. In this work, the clustering problem has been formulated as an optimization task and is solved using a modified DE algorithm. To reduce the computational time, a hybrid k-means with DE method has also been proposed. The new algorithms were tested on a number of document datasets. Comparison with k-means, a state of the art PSO and one recently proposed real coded GA based text clustering methods reflects the superiority of the proposed techniques in terms of speed and quality of clustering.
In this paper, we propose a new closed-form dynamic model of interaction forces between two interacting robotic modules and a methodology to control the interaction forces by using inherent kinematic redundancy of rob...
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In this paper, we propose a new closed-form dynamic model of interaction forces between two interacting robotic modules and a methodology to control the interaction forces by using inherent kinematic redundancy of robotic systems. To show the usefulness of controlling interaction forces, two exemplary cases are introduced. The first example investigates the interaction force between a mobile platform and a serial robot mounted on the platform. The interaction force between the two modules is controlled so that the motion of the mobile platform can be controlled in a desired way. The second example deals with interaction between a serial robot and a human operator. An interaction force is controlled so that the human operator does not feel uncomfortable when the operator performs a designed trajectory motion in cooperation with the robot
This presentation builds on panel discussions that began at the ASEE 2004 National Conference and continued at the 2005 Conference. Our focus is on promoting diversity in engineering education, with an emphasis on gra...
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The steady national decline in women engineering students persists despite a plethora of programs and camps at engineering colleges around the country aimed at attracting girls into engineering and technical fields.1D...
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This paper analyzes the effect of custom error control schemes on the energy efficiency in Bluetooth sensor networks. The energy efficiency metric considers in just one parameter the energy and reliability constraints...
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This paper analyzes the effect of custom error control schemes on the energy efficiency in Bluetooth sensor networks. The energy efficiency metric considers in just one parameter the energy and reliability constraints of the wireless sensor networks. New packet types are introduced using some error control strategies in the AUX1 packet, such as Hamming and BCH codes, with and without CRC for error detection. Two adaptive techniques are proposed that change the error control strategy based on the number of hops traversed by a packet through the network. The performance results are obtained through simulations in a channel with Rayleigh fading for networks with different number of hops, showing that error control can improve the energy efficiency of a Bluetooth-based sensor network.
This article presents a framework to hybridize the rough set theory with a famous swarm intelligence algorithm known as Particle Swarm Optimization (PSO). The hybrid rough-PSO technique has been used for grouping the ...
This article presents a framework to hybridize the rough set theory with a famous swarm intelligence algorithm known as Particle Swarm Optimization (PSO). The hybrid rough-PSO technique has been used for grouping the pixels of an image in its intensity space. Medical and remote sensing satellite images become corrupted with noise very often. Fast and efficient segmentation of such noisy images (which is essential for their further interpretation in many cases) has remained a challenging problem for years. In this work, we treat image segmentation as a clustering problem. Each cluster is modeled with a rough set. PSO is employed to tune the threshold and relative importance of upper and lower approximations of the rough sets. Davies-Bouldin clustering validity index is used as the fitness function, which is minimized while arriving at an optimal partitioning.
Modules that are swapped dynamically at run-time on an FPGA have varying communication needs over time. In order to support this, we aim to generate a wiring infrastructure that caters for the dynamically-changing mod...
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Modules that are swapped dynamically at run-time on an FPGA have varying communication needs over time. In order to support this, we aim to generate a wiring infrastructure that caters for the dynamically-changing module interfaces. This, however, imposes a regular structure for laying out modules on a device, which may result in longer inter-module wiring paths as compared to traditional methods where the netlists are flattened. This paper studies placing modules within a structured layout to compare resulting circuit speeds with those obtained by traditional methods. Our results indicate that the difference in critical path delay is high at very low utilisation, but that the overhead is absorbed as the number of modules and interconnection density increases to realistic levels. The authors conclude that implementing such a wiring infrastructure has manageable overheads while having the added advantage of being amenable to dynamic reconfiguration
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