• Title/Summary/Keyword: run-by-run control

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Development of the autnomous road vehicle (무인 자동차 개발 연구)

  • 최진욱;한민홍
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10a
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    • pp.88-93
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    • 1993
  • This paper introduces an ARV(Autonomous Road Vehicle) system which can run on orads without help of a driver by detecting road boundaries through computer vision. This vehicle can also detect obstacles in front through sonar sensors and infrared sensors. This system largely consists of a handle steering module and a braking module. From road boundaries, the steering module determines handle turn angle. The braking module stops or decelerates to avoid collision depending on the relative speeds and distance to the obstacles detected by different sensors. This ARV system has been implemented in a small jeep and can run 30-40 km/h city traffic. In this paper, we illustrate the structure of the ARV systems and its operation principle.

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A study on the improvement of robustness of the controller by the supervision functions (감독기능에 의한 제어기의 견실성 향상에 관한 연구)

  • 이창구;김성중
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10a
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    • pp.1063-1067
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    • 1991
  • In this paper, we present a supervision and coordination level monitoring the adaptive controller and taking appropriate ,actions if malfunctions are detected. Supervision and coordination level are consist of start-up part and run-time part. The start-up part involves tasks for the configuration and the implementation of controllers, and the run-time part involves tasks for the supervision and coordination of the controllers in closed-loop operation. Also, we show how a supervision level and a coordination level can be designed and what basic elements should be included. Finally, we show the robustness of this scheme by experimental results for task model.

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Temperature and Property Control of High Strength Steel in Hot Strip Mills (열간압연 고강도강의 온도 및 재질제어)

  • Park, Cheol-Jae
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.20 no.6
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    • pp.817-823
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    • 2011
  • This paper proposes a cooling stop temperature control(CST) and a phase transformation control(PTR) which aim at obtaining the uniform temperature and quality along the longitudinal direction of the high strength steel on the run-out table(ROT) process. The problems of the temperature control are analyzed for the conventional steel and the new control concepts are derived from a time-temperature transformation(TTT) diagram. The proposed control technologies are verified from the simulation results under the temperature prediction model by the heat transfer governing equation, and the temperature estimation simulator. It is shown through the field test of the hot strip mills that the phase transformation ratio of the high strength steel is considerably improved by the proposed temperature controls.

Tool-Setup Monitoring of High Speed Precision Machining Tool

  • Park, Kyoung-Taik;Shin, Young-Jae;Kang, Byung-Soo
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.956-959
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    • 2004
  • Recently the monitoring system of tool setting in high speed precision machining center is required for manufacturing products that have highly complex and small shape, high precision and high function. It is very important to reduce time to setup tool in order to improve the machining precision and the productivity and to protect the breakage of cutting tool as the shape of product is smaller and more complex. Generally, the combination of errors that geometrical clamping error of fixing tool at the spindle of machining tool and the asynchronized error of driving mechanism causes that the run-out of tool reaches to 3$^{\sim}$20 times of the thickness of cutting chip. And also the run-out is occurred by the misalignment between axis of tool shank and axis of spindle and spindle bearing in high speed rotation. Generally, high speed machining is considered when the rotating speed is more than 8,000 rpm. At that time, the life time of tool is reduced to about 50% and the roughness of machining surface is worse as the run-out is increased to 10 micron. The life time of tool could be increased by making monitoring of tool-setup easy, quick and precise in high speed machining tool. This means the consumption of tool is much more reduced. And also it reduces the manufacturing cost and increases the productivity by reducing the tool-setup time of operator. In this study, in order to establish the concept of tool-setup monitoring the measuring method of the geometrical error of tool system is studied when the spindle is stopped. And also the measuring method of run-out, dynamic error of tool system, is studied when the spindle is rotated in 8,000${\sim}$60,000 rpm. The dynamic phenomena of tool-setup are analyzed by implementing the monitoring system of rotating tool system and the non-contact measuring system of micro displacement in high speed.

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Design St Implementation of a High-Speed Navigation Computer for Strapdown INS (스트랩다운 관성항법시스템 고속 항법컴퓨터 설계와 구현)

  • 김광진;최창수;이태규
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.29-29
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    • 2000
  • This paper describes the design and implementation of a high-speed navigation computer to achieve precision navigation performance with Strapdown INS. The navigation computer inputs are velocity and angular increment data from the ISA at the signal of the 2404Hz interrupt and performs the removal of gyro block motion and the compensation of high dynamic errors at the 200Hz. For high-speed and high-accuracy, the computer consists of the 68040 micro-processor, 128k Memories, FPGAs, and so on. We show that the computer satisfies the required performance by In-Run navigation tests.

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Sectoral Contribution to Economic Development in India: A Time-Series Co-Integration Analysis

  • SOLANKI, Sandip;INUMULA, Krishna Murthy;CHITNIS, Asmita
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.9
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    • pp.191-200
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    • 2020
  • This research paper examines the causal relationship between India's economic growth and sectoral contribution to Gross Domestic Product (GDP) and vice versa, in the short-run and long-run, over a 10 years time period. Johansen's method of cointegration is used to study the cointegration between the sectoral contributions to Indian GDP vis-à-vis India's economic growth. Further, the route of interconnection between economic growth and sectoral contribution is tested by using Vector Auto Regression (VAR) model. Special attention was given for investigating impulse responses of economic growth depending on the innovations in sectoral contribution using time-series data from 1960 to 2015. This paper highlighted a dynamic co-relationship among industrial sector contribution and agricultural sector contribution and economic development. In the long run, one percent change in industrial sector contribution causes an increase of 3.42 percent in the economic growth and an increase of 1.12 percent in the primary sector contribution, while in the short run industrial and service sector contributions showed significant impact on economic development and agriculture sector. The changing composition of sector contribution is going to be an important activity for the policymakers to monitor and control where the technology and integration of sectors play a significant role in economic development.

A Control Chart for Gamma Distribution using Multiple Dependent State Sampling

  • Aslam, Muhammad;Arif, Osama-H.;Jun, Chi-Hyuck
    • Industrial Engineering and Management Systems
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    • v.16 no.1
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    • pp.109-117
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    • 2017
  • In this article, a control chart based on multiple dependent (or deferred) state sampling for the gamma distributed quality characteristic is proposed using the gamma to normal transformation. The proposed control chart has two pairs of control limits, which can be determined by considering the in-control average run length (ARL). The shift in the scale parameter of a gamma distribution is considered and the out-of-control ARL is evaluated. The performance of the proposed chart has been shown for different levels of the parameters of the proposed control chart. It is also shown that the proposed chart is better than the Shewhart chart in terms of ARLs. A case study with a real data has been included for the practical usage of the proposed scheme.

A Study of Semiconductor Process Control using Dual Damping EWMA (Dual Damping EWMA를 이용한 효율적인 반도체 공정 제어에 관한 연구)

  • Kim, Seon-Eok;Ko, Hyo-Heon;Kim, Jih-Yun;Kim, Sung-Shick
    • IE interfaces
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    • v.21 no.2
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    • pp.141-150
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    • 2008
  • In this paper, an efficient control method for semiconductor fabrication process is presented. Generally, control is performed with data which is under the influence of process disturbance. EWMA is one of the most popular control methods in semiconductor fabrication that effectively deals with varying process condition. A new method using EWMA, called the Dual Damping EWMA, is presented in this study to reduce over-control by separating weight factor of input and output. The goal is to reflect Drift but reduce the effects of White noise in run to run control. Simulation is performed to evaluate the performance of DPEWMA and to compare with EWMA and Double EWMA.

Multivariate Process Control Chart for Controlling the False Discovery Rate

  • Park, Jang-Ho;Jun, Chi-Hyuck
    • Industrial Engineering and Management Systems
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    • v.11 no.4
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    • pp.385-389
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    • 2012
  • With the development of computer storage and the rapidly growing ability to process large amounts of data, the multivariate control charts have received an increasing attention. The existing univariate and multivariate control charts are a single hypothesis testing approach to process mean or variance by using a single statistic plot. This paper proposes a multiple hypothesis approach to developing a new multivariate control scheme. Plotted Hotelling's $T^2$ statistics are used for computing the corresponding p-values and the procedure for controlling the false discovery rate in multiple hypothesis testing is applied to the proposed control scheme. Some numerical simulations were carried out to compare the performance of the proposed control scheme with the ordinary multivariate Shewhart chart in terms of the average run length. The results show that the proposed control scheme outperforms the existing multivariate Shewhart chart for all mean shifts.

A Study Short Run Production Cusum Individual X Chart & Moving Range Chart (단납기 생산체계의 누계치 관리도와 유동성 관리도에 관한 연구)

  • Kim Je-Hong
    • Journal of the Korea Society of Computer and Information
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    • v.9 no.4 s.32
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    • pp.215-220
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    • 2004
  • Production management confronted the environment of infinite competition should be prepared to abrupt variations of management environment and have the ability to be changed in short term. It has to be studied, the control method of products that correspond to multi-functionalization and reduced product life which is caused by high-quality and varied customers demands. As a process control method, we most be able not only to control varies characteristic in a control at once but also to detected special values quickly for high-quality. In this paper a control method referred above is presented.

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