• Title, Summary, Keyword: direct (inverse) system

Search Result 65, Processing Time 0.039 seconds

Neural Network Based Disturbance Canceler with Feedback Error Learning for Nonholonomic Mobile Robots

  • Izumi, Kiyotaka;Syam, Rafiuddin;Watanabe, Keigo;Kiguchi, Kazuo
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • /
    • pp.443-446
    • /
    • 2003
  • Conventional disturbance rejection methods have to derive the inverse model of a system. However, the inverse model of n nonholonomic system is not unique, because an inverse it changes depending on initial conditions and desired values. A kind of internal model control (IMC) using feedback error learning is discussed for the motion control of nonholonomic mobile robots in this paper, The present method is different from a conventional IMC whose control system consists of an inverse model, a direct model and a filter. The present disturbance rejection method need not use a direct model, where the remaining two elements are composed of the same inverse model based on neural networks.

  • PDF

A Study on the Sparse Matrix Method Useful to the Solution of a Large Power System (전력계통 해석에 유용한 "스파스"행렬법에 관한 연구)

  • 한만춘;신명철
    • 전기의세계
    • /
    • v.23 no.3
    • /
    • pp.43-52
    • /
    • 1974
  • The matrix inversion is very inefficient for computing direct solutions of the large spare systems of linear equations that arise in many network problems as a large electrical power system. Optimally ordered triangular factorization of sparse matrices is more efficient and offers the other important computational advantages in some applications with this method. The direct solutions are computed from sparse matrix factors instead of a full inverse matrix, thereby gaining a significant advantage is speed and computer memory requirements. In this paper, it is shown that the sparse matrix method is superior to the inverse matrix method to solve the linear equations of large sparse networks. In addition, it is shown that the sparse matrix method is superior to the inverse matrix method to solve the linear equations of large sparse networks. In addition, it is shown that the solutions may be applied directly to sove the load flow in an electrical power system. The result of this study should lead to many aplications including short circuit, transient stability, network reduction, reactive optimization and others.

  • PDF

A DIRECT INVERSE-BASED CROSS-TALK CANCELLATION METHOD FOR STEREO AUDIO SYSTEMS (직접 역필터 설계법을 이용한 스테레오 재생시스템의 Cross-talk 제거)

  • Kim, Sang-Myeong;Dogeun Han;Semyung Wang
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • /
    • pp.559-564
    • /
    • 2002
  • Cross-talk cancellation, inverse filter design or deconvolution in a generic term, is a vital process for a virtual sound realization in the stereo sound reproduction system. Most, if not all, of the design algorithms available for the inverse filter are based on a linearized model of the real physical plant. The result of such a plant-based design method, which may be referred to here as the indirect method, is biased due to both modelling and inversion errors. This paper presents a novel direct cross-talk cancellation method that may be free from the inversion error. The direct method can directly models the inverse filter by a suitable rearrangement of the input and output ports of the original plant so that no inversion is required here. Advantages are discussed with various experiments in an anechoic chamber using a PC soundcard. Binaural reproduction tests conducted showed that the conventional indirect method yields about 8 % reproduction performance error on both ear positions, whereas the direct method offers about 3 %.

  • PDF

DERIVED CUP PRODUCT AND (STRICTLY) DERIVED GROUPS

  • Lee, Dae-Woong
    • Bulletin of the Korean Mathematical Society
    • /
    • v.35 no.4
    • /
    • pp.791-807
    • /
    • 1998
  • The purpose of this paper is to construct a ring with unity under the derived cup product on the cochain groups of the inverse system and an isomorphism which is useful as the computation of a derived group by deleting the suitable terms in the directed set D. Moreover we apply these results to the K-theory.

  • PDF

Control Methodology of Inverse Response Process

  • Pratch, Tontirittiphol;Kiattisak, Kumwachara;Mongkol, Janchookiat
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.48.6-48
    • /
    • 2002
  • in this paper, each methodology, e.g. normal single PID controller, direct synthesis method and inverse response compensator, will be compared to determine the best inverse response plant control method, by based on the appearance of the control performance and robustness from the simulation results. The flexibility of being able to maintain the system stability during the presence of plant model mismatch is one of the criteria to measure the robustness of overall control system. Once, plant has changed the condition, the model will need to be updated. Hence, the designed controller will not work properly. The caused of plant model mismatch is stayed by definition unknown but the most possib...

  • PDF

A Study on the Application of SVD to an Inverse Problem in a Cantilever Beam with a Non-minimum Phase (비최소 위상을 갖는 외팔보에서 SVD를 이용한 역변환 문제에 관한 연구)

  • 이상권;노경래;박진호
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.11 no.9
    • /
    • pp.431-438
    • /
    • 2001
  • This paper present experimental results of source identification for non-minimum phase system. Generally, a causal linear system may be described by matrix form. The inverse problem is considered as a matrix inversion. Direct inverse method can\`t be applied for a non-minimum phase system, the reason is that the system has ill-conditioning. Therefore, in this study to execute an effective inversion, SVD inverse technique is introduced. In a Non-minimum phase system, its system matrix may be singular or near-singular and has one more very small singular values. These very small singular values have information about a phase of the system and ill-conditioning. Using this property we could solve the ill-conditioned problem of the system and then verified it for the practical system(cantilever beam). The experimental results show that SVD inverse technique works well for non-minimum phase system.

  • PDF

Analysis of Relationship between Body and Gimbal Motion Through Experiment of a Single-wheel Robot Based on an Inverse Gyroscopic Effect (외바퀴 로봇의 역자이로 효과에 의한 바디 모션과 김벌 모션의 실험을 통한 관계 분석)

  • Lee, Sang-Deok;Jung, Seul
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.21 no.11
    • /
    • pp.1064-1069
    • /
    • 2015
  • Control Moment Gyro (CMG) has been used as an indirect actuator of a single-wheel robot system GYROBO, developed at Chungnam National University. The flip motion of the gimbal system produces the gyroscopic motion onto the body system while the body motion also produces the gyroscopic motion onto the gimbal system inversely. In this paper, the intuitive equation of the inverse gyroscopic effect is derived as the direct relation between the rate of the body system and the rate of the gimbal system. Experiments on the inverse gyroscopic effect under the chaotically generated disturbance are conducted. Experimental data are approximated by a linear equation using the least square method.

Adaptive Position Controller Design of Electro-hydraulic Actuator Using Approximate Model Inversion (근사적 모델 역변환을 활용한 전기-유압 액추에이터의 적응 위치 제어기 설계)

  • Lee, Kyeong Ha;Baek, Seung Guk;Koo, Ja Choon
    • The Journal of Korea Robotics Society
    • /
    • v.11 no.2
    • /
    • pp.92-99
    • /
    • 2016
  • An electro-hydraulic actuator (EHA) is widely used in industrial motion systems and the increasing bandwidth of EHA position control is important issue. The model-inverse feedforward controller is known to extend the bandwidth of system. When the system has non-minimum phase (NMP) zeros, direct model inversion makes system unstable. To overcome this problem, an approximate model-inverse method is used. A representative approximate model inversion method is zero phase error tracking control (ZPETC). However, if zeros locate right half plane of z-plane, the approximate inverse model amplifies the high-frequency response. In this paper, to solve the problem of ZPETC, an adaptive model-inverse control is proposed. The adaptive algorithm updates feedforward term in real-time. The effectiveness of the proposed adaptive model-inverse position control strategy is verified by comparison with typical proportional-integral (PI) control and feedforward control by experiments. As a result, the proposed adaptive controller extends the bandwidth of EHA position control.

Composite adaptive neural network controller for nonlinear systems (비선형 시스템제어를 위한 복합적응 신경회로망)

  • 김효규;오세영;김성권
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.14-19
    • /
    • 1993
  • In this paper, we proposed an indirect learning and direct adaptive control schemes using neural networks, i.e., composite adaptive neural control, for a class of continuous nonlinear systems. With the indirect learning method, the neural network learns the nonlinear basis of the system inverse dynamics by a modified backpropagation learning rule. The basis spans the local vector space of inverse dynamics with the direct adaptation method when the indirect learning result is within a prescribed error tolerance, as such this method is closely related to the adaptive control methods. Also hash addressing technique, similar to the CMAC functional architecture, is introduced for partitioning network hidden nodes according to the system states, so global neuro control properties can be organized by the local ones. For uniform stability, the sliding mode control is introduced when the neural network has not sufficiently learned the system dynamics. With proper assumptions on the controlled system, global stability and tracking error convergence proof can be given. The performance of the proposed control scheme is demonstrated with the simulation results of a nonlinear system.

  • PDF

Target Marketing using Inverse Association Rule (역 연관규칙을 이용한 타겟 마케팅)

  • 황준현;김재련
    • Proceedings of the Korea Inteligent Information System Society Conference
    • /
    • /
    • pp.241-249
    • /
    • 2002
  • Making traditional plan of target marketing based on Association Rule has brought restriction to obtain the target of marketing. This paper is to present Inverse Association Rule as a new association rule for target marketing. Inverse Association Rule does not use information about relation between items that customers purchase like Association Rule, but use information about relation between items that customers do not pruchase. By adding Inverse Association Rule to target marketing, we generate new marketing rule to look for new target of marketing. From new marketing rule, this paper is to show direct marketing about target item and indirect marketing about another item associated with target item to sell target item. The reason is that sales of the item associated with target item have an influence on sales of target item.

  • PDF