• Title/Summary/Keyword: neural network.

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Intelligent Control of Mobile robot Using Fuzzy Neural Network Control Method (퍼지-신경망 제어기법을 이용한 Mobile Robot의 지능제어)

  • 정동연;김용태;한성현
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.10a
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    • pp.235-240
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    • 2002
  • This paper presents a new approach to the design of cruise control system of a mobile robot with two drive wheel. The proposed control scheme uses a Gaussian function as a unit function in the fuzzy neural network, and back propagation algorithm to train the fuzzy neural network controller in the framework of the specialized learning architecture. It is proposed a learning controller consisting of two neural network-fuzzy based on independent reasoning and a connection net with fixed weights to simply the neural networks-fuzzy. The performance of the proposed controller is shown by performing the computer simulation for trajectory tracking of the speed and azimuth of a mobile robot driven by two independent wheels.

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An Intelligent Control of TRack Vehicle Using Fuzzy-Neural Network Control Method (퍼지-신경회로망 제어기법에 의한 궤도차량의 지능제어)

  • 신행봉;김용태;조길수;한성현
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.05a
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    • pp.210-215
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    • 1999
  • In this paper, a new approach to the dynamic control technique for track vehicle system using fuzzy-neural network control technique is proposed. The proposed control scheme uses a Gaussian function as a unit function in the neural network-fuzzy, and back propagation algorithm to train the fuzzy-neural network controller in the framework of the specialized learning architecture. It is proposed a learning controller consisting of two neural network-fuzzy based on independent reasoning and a connection net with fixed weights to simply the neural networks-fuzzy. The performance of the proposed controller is shown by simulation for trajectory tracking of the speed and azimuth of a track vehicle.

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Neural Network Parameter Estimation of IPMSM Drive using AFLC (AFLC를 이용한 IPMSM 드라이브의 NN 파라미터 추정)

  • Ko, Jae-Sub;Choi, Jung-Sik;Chung, Dong-Hwa
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.2
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    • pp.293-300
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    • 2011
  • A number of techniques have been developed for estimation of speed or position in motor drives. The accuracy of these techniques is affected by the variation of motor parameters such as the stator resistance, stator inductance or torque constant. This paper is proposed a neural network based estimator for torque and stator resistance and adaptive fuzzy learning contrroller(AFLC) for speed control in IPMSM Drives. AFLC is chaged fuzzy rule base by rule base modifier for robust control of IPMSM. The neural weights are initially chosen randomly and a model reference algorithm adjusts those weights to give the optimum estimations. The neural network estimator is able to track the varying parameters quite accurately at different speeds with consistent performance. The neural network parameter estimator has been applied to slot and flux linkage torque ripple minimization of the IPMSM. The validity of the proposed parameter estimator and AFLC is confirmed by comparing to conventional algorithm.

Internet Traffic Control Using Dynamic Neural Networks

  • Cho, Hyun-Cheol;Fadali, M. Sami;Lee, Kwon-Soon
    • Journal of Electrical Engineering and Technology
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    • v.3 no.2
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    • pp.285-291
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    • 2008
  • Active Queue Management(AQM) has been widely used for congestion avoidance in Transmission Control Protocol(TCP) networks. Although numerous AQM schemes have been proposed to regulate a queue size close to a reference level, most of them are incapable of adequately adapting to TCP network dynamics due to TCP's non-linearity and time-varying stochastic properties. To alleviate these problems, we introduce an AQM technique based on a dynamic neural network using the Back-Propagation(BP) algorithm. The dynamic neural network is designed to perform as a robust adaptive feedback controller for TCP dynamics after an adequate training period. We evaluate the performances of the proposed neural network AQM approach using simulation experiments. The proposed approach yields superior performance with faster transient time, larger throughput, and higher link utilization compared to two existing schemes: Random Early Detection(RED) and Proportional-Integral(PI)-based AQM. The neural AQM outperformed PI control and RED, especially in transient state and TCP dynamics variation.

Prediction of Nonlinear Sequences by Self-Organized CMAC Neural Network (자율조직 CMAC 신경망에 의한 비선형 시계열 예측)

  • 이태호
    • Journal of the Institute of Convergence Signal Processing
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    • v.3 no.4
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    • pp.62-66
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    • 2002
  • An attempt of using SOCMAC neural network for the prediction of a nonlinear sequence, which is generated by Mackey-Glass equation, is reported. The ,report shows the SOCMAC can handle a system with multi-dimensional continuous inputs, which has been considered very difficult, if not impossible, task to be implemented by a CMAC neural network because of a huge amount of memory required. Also, an improved training method based on the variable receptive fields is proposed. The Performance ranged somewhere around those of TDNN and BP neural networks.

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Neural Network Based Rudder-Roll Damping Control System for Ship

  • Nguyen, Phung-Hung;Jung, Yun-Chul
    • Journal of Navigation and Port Research
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    • v.31 no.4
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    • pp.289-293
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    • 2007
  • In this paper, new application of adaptive neural network to design a ship's Rudder-Roll Damping(RRD) control system is presented Firstly, the ANNAI neural network controller is presented. Secondly, new RRD control system using this neural network approach is developed. It uses two neural network controllers for heading control and roll damping control separately. Finally, Computer simulation of this RRD control system is carried out to compare with a linear quadratic optimal RRD control system; discussions and conclusions are provided. The simulation results show the feasibility of using ANNAI controller for RRD. Also, the necessity of mathematical ship model in designing RRD control system is removed by using NN control technique.

Precision Position Control of a Piezoelectric Actuator Using Neural Network (신경 회로망을 이용한 압전구동기의 정밀위치제어)

  • Kim, Hae-Seok;Lee, Byung-Ryong;Park, Kyu-Youl
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.11
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    • pp.9-15
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    • 1999
  • A piezoelectric actuator is widely used in precision positioning applications due to its excellent positioning resolution. However, the piezoelectric actuator lacks in repeatability because of its inherently high hysteresis characteristic between voltage and displacement. In this paper, a controller is proposed to compensate the hysteresis nonlinearity. The controller is composed of a PID and a neural network part in parallel manner. The output of the PID controller is used to teach the neural network controller by the unsupervised learning method. In addition, the PID controller stabilizes the piezoelectric actuator in the beginning of the learning process, when the neural network controller is not learned. However, after the learning process the piezoelectric actuator is mainly controlled by the neural netwok controller. In this paper, the excellent tracking performance of the proposed controller was verified by experiments and was compared with the classical PID controller.

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A neural network solver for differential equations

  • Wang, Qianyi;Aoyama, Tomoo;Nagashima, Umpei;Kang, Eui-Sung
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.88.4-88
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    • 2001
  • In this paper, we propose a solver for differential equations, using a multi-layer neural network. The multi-layer neural network is a transformer function originally where the function is differential and the explicit representation has been developed. The learning determines the response of neural networks; however, the response is not equal to the output values. The differential relations are also the response. The differential conditions can be also set as teaching data; therefore, there is a possibility to reach a new solver for the differential equations. Since it is unknown how to define the input data for the neural network solver during long terms, we could not derive the expressions. Recently, the analogue type neural network is known and it transforms any vector to another The "any" must be...

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A study on correspondence problem of stereo vision system using self-organized neural network

  • Cho, Y.B.;Gweon, D.G.
    • Journal of the Korean Society for Precision Engineering
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    • v.10 no.4
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    • pp.170-179
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    • 1993
  • In this study, self-organized neural network is used to solve the vorrespondence problem of the axial stereo image. Edge points are extracted from a pair of stereo images and then the edge points of rear image are assined to the output nodes of neural network. In the matching process, the two input nodes of neural networks are supplied with the coordi- nates of the edge point selected randomly from the front image. This input data activate optimal output node and its neighbor nodes whose coordinates are thought to be correspondence point for the present input data, and then their weights are allowed to updated. After several iterations of updating, the weights whose coordinates represent rear edge point are converged to the coordinates of the correspondence points in the front image. Because of the feature map properties of self-organized neural network, noise-free and smoothed depth data can be achieved.

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Mixed-input neural networks for daylight prediction

  • Thanh Luan LE;Sung-Ah KIM
    • International conference on construction engineering and project management
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    • 2024.07a
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    • pp.973-979
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    • 2024
  • In this research, we present the implementation of a mixed-input neural network for daylight prediction in the architectural design process. This approach harnesses the advantages of both image and numerical inputs to construct a robust neural network model. The hybrid model consists of two branches, each handling in-depth information about the building. Consequently, this model can effectively accommodate a wide range of building layouts, incorporating additional information for enhanced predictions. The building data was created utilizing PlanFinder in Rhino Grasshopper, while simulation data were generated using Honeybee and Ladybug. Weather data were collected from three distinct localities in Vietnam: Ha Noi, Da Nang, and Ho Chi Minh City. The neural network demonstrates outstanding performance, achieving an R-squared (R2) value of 0.95 and the overall percentage difference in the testing dataset ranges from 0 to 20.7%.