• Title/Summary/Keyword: Redundancy analysis

Search Result 382, Processing Time 0.027 seconds

Landing Motion Analysis of Human-Body Model Considering Impact and ZMP Condition (충격과 ZMP 조건을 고려한 인체 모델의 착지 동작 해석)

  • So Byung Rok;Kim Wheekuk;Yi Byung-Ju
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.11 no.6
    • /
    • pp.543-549
    • /
    • 2005
  • This paper deals with modeling and analysis fer the landing motion of a human-body model. First, the dynamic model of a floating human body is derived. The external impulse exerted on the ground as well as the internal impulse experienced at the joints of the human body model is analyzed. Second, a motion planning algorithm exploiting the kinematic redundancy is suggested to ensure stability in terms of ZMP stability condition during a series of landing phases. Four phases of landing motion are investigated. In simulation, the external and internal impulses experienced at the human joints and the ZMP history resulting from the motion planning are analyzed for two different configurations. h desired landing posture is suggested by comparison of the simulation results.

Mobility Analysis and Flexible Motion Control of Mobile Manipulator System (이동 매니퓰레이터 시스템의 운동성 해석과 유연한 동작 제어)

  • Lim, Mee-Seub;Oh, Sang-Rok;Kim, Kwang-Bae;Yi, Byung-Ju;Lim, Joon-Hong
    • Proceedings of the KIEE Conference
    • /
    • 2000.07d
    • /
    • pp.2735-2737
    • /
    • 2000
  • In this paper, we deal with modeling and analysis for mobile manipulator systems. In order to avoid the difficulties occurring due to slippage or unevenness of the terrain, we propose the utilization of minimum actuators. In this case, the resulting systems typically possess kinematic redundancies which can be beneficially employed for correcting the position error. A simple PD control method along with kinematic redundancy is employed to recover position errors for trajectory control in task space. Several primary and secondary criteria utilizing kinematic redundancy of the mobile manipulator system are tested through graphic animation.

  • PDF

High Repair Efficiency BIRA Algorithm with a Line Fault Scheme

  • Han, Tae-Woo;Jeong, Woo-Sik;Park, Young-Kyu;Kang, Sung-Ho
    • ETRI Journal
    • /
    • v.32 no.4
    • /
    • pp.642-644
    • /
    • 2010
  • With the rapid increase occurring in both the capacity and density of memory products, test and repair issues have become highly challenging. Memory repair is an effective and essential methodology for improving memory yield. An SoC utilizes built-in redundancy analysis (BIRA) with built-in self-test for improving memory yield and reliability. This letter proposes a new heuristic algorithm and new hardware architecture for the BIRA scheme. Experimental results indicate that the proposed algorithm shows near-optimal repair efficiency in combination with low area and time overheads.

Reliability Analysis and Fault Tolerance Strategy of TMR Real-time Control Systems (TMR 실시간 제어 시스템의 내고장성 기법 및 신뢰도 해석)

  • Kwak, Seong-Woo;You, Kwan-Ho
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.10 no.8
    • /
    • pp.748-754
    • /
    • 2004
  • In this paper, we propose the Triple Modular Redundancy (TMR) control system equipped with a checkpoint strategy. In this system, faults in a single processor are masked and faults in two or more processors are detected at each checkpoint time. When faults are detected, the rollback recovery is activated to recover from faults. The conventional TMR control system cannot overcome faults in two or more processors. The proposed system can effectively cope with correlated and independent faults in two or more processors. We develop a reliability model for this TMR control system under correlated and independent transient faults, and derive the reliability equation. Then we investigate the number of checkpoints that maximizes the reliability.

Efficient non-linear analysis and optimal design of biomechanical systems

  • Shojaei, I.;Kaveh, A.;Rahami, H.;Bazrgari, B.
    • Biomaterials and Biomechanics in Bioengineering
    • /
    • v.2 no.4
    • /
    • pp.207-223
    • /
    • 2015
  • In this paper a method for simultaneous swift non-linear analysis and optimal design/posture of mechanical/biomechanical systems is presented. The method is developed to get advantages of iterations in non-linear analysis and/or generations in genetic algorithm (GA) for the purpose of efficient analysis within the optimal design/posture. The method is applicable for both size and geometry optimizations wherein material and geometry non-linearity are present. In addition to established mechanical systems, the method can solve biomechanical models of human musculoskeletal system. Optimization-based procedures are popular methods for resolving the redundancy at joints wherein the number of unknown muscle forces is far more than the number of equilibrium equations. These procedures involve optimization of a cost function(s) which is assumed to be consistent with the central nervous system's strategy when activating muscles to assure equilibrium. However, because of the complexity of biomechanical problems (i.e., due to non-linear biomaterial, large deformation, redundancy of the problem and so on) efficient analysis are required within optimization procedures as suggested in this paper.

Reliability Analysis of Redundant Architecture of Dependable Control System (다중화 구조 제어시스템에 대한 신뢰도 분석)

  • Noh, Jinpyo;Park, Jaehyun;Son, Kwang-Seop;Kim, Dong-Hoon
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.19 no.4
    • /
    • pp.328-333
    • /
    • 2013
  • Since a slight malfunction of control systems in a nuclear power plant may cause huge catastrophes, such control systems usually have multiple redundancy and reliable features, and their reliability and availability should be analyzed and verified thoroughly. This paper performed the reliability analysis of the SPLC (Safety Programmable Logic Controller) that is under developed as the control systems for the next generation nuclear power plant. One of the key features of SPLC is that it has multiple redundancy modes as faults happen, which means the reliability analysis for one fixed redundant model is not enough to analyze the reliability of SPLC. With considering this reconfigurable concept, FTA (Fault Tree Analysis) was used to capture fault-relationship among sub-modules. The analysis results show that MTTF (Mean Time to Fault) of SPLC is 45,080 hours, which is a about 4.5 times longer than the regulation, 10,000 hours.

An Analysis Region Virtualization Scheme for Built-in Redundancy Analysis Considering Faulty Spares (불량 예비셀을 고려한 자체 내장 수리연산을 위한 분석 영역 가상화 방법)

  • Jeong, Woo-Sik;Kang, Woo-Heon;Kang, Sung-Ho
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.47 no.12
    • /
    • pp.24-30
    • /
    • 2010
  • In recent memories, repair is an unavoidable method to maintain its yield and quality. The probability of defect occurence on spare lines has been increased through the growth of the density of recent memories with 2 dimensional spare architecture. In this paper, a new analysis region virtualization scheme is proposed. the analysis region virtualization scheme can be applied with any BIRA (built-in redundancy analysis) algorithms without the loss of their repair rates. The analysis region virtualization scheme can be a viable solution for BIRA considering the faulty spare lines of the future high density memories.

Hardware and Software Dependability Analysis of Embedded AVTMR(All Voting Triple Modular Redundancy) System (내장형 AVTMR 시스템의 하드웨어 및 소프트웨어 신뢰성 분석)

  • Kim, Hyun-Ki
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.34 no.7B
    • /
    • pp.744-750
    • /
    • 2009
  • In this paper, the unified Markov modeling of hardware and software for AVTMR(AlI Voting Triple Modular Redundancy) system is proposed and the dependability is analyzed. In hardware case, a failure rate is fixed to no time varying parameter. But, in software case, failure rate is applied with time varying parameter. Especially, the dependability(Reliability, Availability, Maintainability, Safety) of software is analyzed with G-O/NHPP for Markov modeling. The dependability of single and AVTMR system is analyzed and simulated with a unified Markov modeling method, and the characteristic of each system is compared accroding to failure rate. This kind of fault tolerat system can be applied to an airplane and life critical system to meet the requirement for a specific requirement.

Optimization of Redundancy by using Genetic Algorithm for Reliability of Plant Protection Controller (플랜트 보호 제어기의 신뢰도분석과 유전알고리듬을 이용한 다중성의 최적화)

  • Yu, Dong-Wan;Kim, Dong-Hun;Park, Hui-Yun;Gu, In-Su;Seo, Bo-Hyeok
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.49 no.9
    • /
    • pp.504-511
    • /
    • 2000
  • The reliability of system is to become a important concern in developed industry. The controller based on the reliability is so important position. PPC(Plant Protection Controller) is for plant protection and human life by fault detection and control action against the transient condition of plant. The protection system of the nuclear reactor and chemical reactor are representative of PPC. This paper presents analysis of PPC relaibility formal problem statement of optimal redundancy based on the reliability for PPC. And the problem is optimized by genetic algorithm, The genetic algorithms is useful algorithm in case of large searching complex gradient existence local minimum. The genetic algorithms is useful algorithm is case of large searching complex gradient existence local minimum. The ability and effectiveness of the proposed optimization is demonstrated by the target reliability of one channel. PPC. using the failure rate based on the MIL-HDBK-217

  • PDF

Optimum Inner and Outer Code Rates for Concatenated Codes in Gaussian Binary Symmetric Channels (가우시안 이진 대칭 채널에서 쇄상부호의 최적 내.외 부호율에 관한 연구)

  • Lee, Ye Hoon
    • Journal of Satellite, Information and Communications
    • /
    • v.9 no.2
    • /
    • pp.110-113
    • /
    • 2014
  • In this paper, we address a problem of finding the optimum inner and outer code rates for a concatenated code in Gaussian binary symmetric channels. Clearly, as the inner code rate decreases, the error detection capability of the inner code increases. However, decreasing the inner code rate implies a decrease in error-correction capability of the outer code when overall code rate is fixed. With this notion in mind, we examine the optimum distribution of redundancy on the outer and inner codes to achieve a maximum performance gain in the concatenated coding scheme. Our analysis shows that the maximum coding gain can be obtained when the inner code rate is maximized and the outer code rate is minimized under the constraint of total code rate is fixed.