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Keum Shik Hong - One of the best experts on this subject based on the ideXlab platform.

  • Robust time-delay control of a Reclaimer
    KSME International Journal, 1999
    Co-Authors: Keum Shik Hong
    Abstract:

    In this paper, a robust time delay control for a Reclaimer is investigated. Supplying the same amount of raw material throughout the reclaimation process, from the raw yard to a sinter plant, is important to keep the quality of the molten steel uniform. As the parameter values of the Reclaimer are not available, the boom rotational dynamics. is modeled as a second order differential equation with unknown coefficients. The unknown parameters in the nominal model are estimated using recursive estimation method. Another important factor in the control problem of a Reclaimer is the large time delay in output measurement. Assuming a multiplicative uncertainty, that accounts for both the unstructured uncertainty neglected in the modeling and the structured uncertainty in the parameter estimation, a robust Smith predictor is designed. A robust stability criterion for the multiplicative uncertainty is derived. Following the work of Goodwin et al. (1992), a quantifying procedure of the multiplicative uncertainty bound, through experiments, is described. Experimental and simulation results are provided.

  • Automatic landing method of a Reclaimer on the stockpile
    IEEE Transactions on Systems Man and Cybernetics Part C (Applications and Reviews), 1999
    Co-Authors: Chintae Choi, Kitae Shin, Keum Shik Hong
    Abstract:

    Large excavation Reclaimers are used to dig ore and transfer it to the blast furnaces that refine the ore into pure metal form. The reclaiming job consists of two operations: (1) landing a Reclaimer bucket on the surface of a pile and (2) slewing its boom with rotating buckets to scoop the ore. An automatic landing method for choosing where to dig in a pile of raw ore is proposed to achieve autonomous reclaiming. The method comprises detecting the shape of a pile, extracting contour lines of the pile, obtaining the joint angles of the Reclaimer and determining an optimal landing point. A 3D range finder was developed with laser radar concepts to detect the shape and height of the ore pile. A series of image processing techniques for extracting the contour line from the 3D range data of a pile is suggested. A height map is obtained from the acquired range data for a pile and a contour map is obtained through image processing steps, including interpolation and edge following. The optimal landing point of the bucket on the contour line is determined so that an overload problem does not occur in the slewing operation and the reclaiming efficiency can be maximized. The algorithm for finding the landing point requires an inverse kinematics solution for the Reclaimer. The forward kinematics of the Reclaimer is first obtained. A constraint equation based on the geometrical relationship is suggested to solve the inverse kinematics of the Reclaimer with redundancy. The proposed method was successfully applied to a working Reclaimer. An autonomous Reclaimer is now being operated in the yards of Kwangyang Steelworks in Korea.

Łucarz M. - One of the best experts on this subject based on the ideXlab platform.

  • Influence of Reclamation Process on the Ecological Quality of Reclaim Sand
    Sciendo, 2017
    Co-Authors: Dereń M., Łucarz M., Roczniak A., Kmita A.
    Abstract:

    In this article, there were presented results of research on influence of reclamation process on the ecological quality of reclaim sand with furan resin used in nonferrous foundry. The quality of reclaimed sand is mainly define by two group of chemical substances from elution of reclaimed sand: Dissolves Organic Carbon (DOC) and Total Dissolves Solids (TDS). Reclaimed sand used in test was prepared in experimental thermal Reclaimer and mechanical vibration Reclaimer REGMAS installed in Faculty of Foundry Engineering at University Of Science and Technology in Krakow. The reference point is molding sand shaking out and crumble in jaw crusher. Test of elution was made in accredited laboratory in Center For Research and Environmental Control in Katowice up to the standard with Dissolves Organic Carbon (DOC) - PN-EN 1484:1999; Total Dissolves Solids (TDS) - PN-EN 15216:2010. The standard for elution test is PN-EN 12457- 4:2006. Except that we were made loss of ignition test, to check how many resin was rest on sand grains

  • Conditions of Thermal Reclamation Process Realization on a Sample of Spent Moulding Sand from an Aluminum Alloy Foundry Plant
    Sciendo, 2017
    Co-Authors: Łucarz M., Dereń M.
    Abstract:

    The results of investigations of thermal reclamation of spent moulding sands originating from an aluminum alloy foundry plant are presented in this paper. Spent sands were crushed by using two methods. Mechanical fragmentation of spent sand chunks was realized in the vibratory Reclaimer REGMAS. The crushing process in the mechanical device was performed either with or without additional crushing-grinding elements. The reclaimed material obtained in this way was subjected to thermal reclamations at two different temperatures. It was found that a significant binder gathering on grain surfaces favors its spontaneous burning, even in the case when a temperature lower than required for the efficient thermal reclamation of furan binders is applied in the thermal Reclaimer. The burning process, initiated by gas burners in the Reclaimer chamber, generates favorable conditions for self-burning (at a determined amount of organic binders on grain surfaces). This process is spontaneously sustained and decreases the demand for gas. However, due to the significant amount of binder, this process is longer than in the case of reclaiming moulding sand prepared with fresh components

  • Investigation of the Results of Combined Reclamation on the Particular Stages of Grain Matrix Recovery
    Sciendo, 2016
    Co-Authors: Łucarz M., Dereń M., Dańko R., Skrzyński M.
    Abstract:

    In this article, there were presented the results of research on combined mechanical and thermal regeneration of waste moulding sand with furfuryl resin originated from one of national foundries manufacturing aluminium alloys castings. Attempts of mechanical reclamation were led on the REGMAS Reclaimer enabling to realize preliminary and primary reclamation with use of two modes of mechanical interactions on waste moulding sand. In the first attempt the Reclaimer worked without any additional regenerating elements, and as the second solution, the Reclaimer operated with additional crushing and abrasive elements to increase the result of primary reclamation. Thermal reclamation was led in the prototypic thermal Reclaimer, enabling to fully control the process of grain matrix recovery. As a result of completed investigations the small efficiency of mechanical reclamation was determined. However, use of combined regeneration allowed for obtaining grain matrix of high purity. Thermal regeneration was conducted in prototypic thermal Reclaimer. Evaluation of reclaim (reclaimed material) quality was carried out in the way of iginition losses and grain-size analysis, surface morphology and also by executing of strength testing of moulding sand prepared on obtained grain matrix for the particular reclamation operations

  • Ecological Aspects of the Performed Thermal Reclamation
    Sciendo, 2015
    Co-Authors: Łucarz M.
    Abstract:

    The thermal analysis results of the selected group of binders and the thermal reclamation of one spent moulding sand with organic binder, are presented in the paper. The reclaiming process of the quartz matrix was performed on the basis of the own method of selecting the reclamation temperature. Taking into account thermogravimetric (TG) analysis results of the binder, the temperature range - required for performing the efficient reclamation of spent moulding sand containing this binder - was indicated. In order to confirm the assumptions, the thermal reclamation operations were carried out at a temperature similar to the determined on the TG basis and - for comparisons - at lower and higher temperatures. During the reclamation operation the reclaim samples were taken for the loss on ignition testing, aimed at the determination of the process efficiency. Temperature in the Reclaimer chamber and gas consumptions were also recorded. On the bases of the thermal analyses, loss on ignition, gas consumption and temperatures of the reclaimed moulding sand bed the recommendations for the realisation of the thermal reclamation were given. These recommendations will allow a better, than currently available, process control in an aspect of decreasing the pyrolysis effect and limiting the emission of substances harmful for the environment

Chintae Choi - One of the best experts on this subject based on the ideXlab platform.

  • Automatic landing method of a Reclaimer on the stockpile
    IEEE Transactions on Systems Man and Cybernetics Part C (Applications and Reviews), 1999
    Co-Authors: Chintae Choi, Kitae Shin, Keum Shik Hong
    Abstract:

    Large excavation Reclaimers are used to dig ore and transfer it to the blast furnaces that refine the ore into pure metal form. The reclaiming job consists of two operations: (1) landing a Reclaimer bucket on the surface of a pile and (2) slewing its boom with rotating buckets to scoop the ore. An automatic landing method for choosing where to dig in a pile of raw ore is proposed to achieve autonomous reclaiming. The method comprises detecting the shape of a pile, extracting contour lines of the pile, obtaining the joint angles of the Reclaimer and determining an optimal landing point. A 3D range finder was developed with laser radar concepts to detect the shape and height of the ore pile. A series of image processing techniques for extracting the contour line from the 3D range data of a pile is suggested. A height map is obtained from the acquired range data for a pile and a contour map is obtained through image processing steps, including interpolation and edge following. The optimal landing point of the bucket on the contour line is determined so that an overload problem does not occur in the slewing operation and the reclaiming efficiency can be maximized. The algorithm for finding the landing point requires an inverse kinematics solution for the Reclaimer. The forward kinematics of the Reclaimer is first obtained. A constraint equation based on the geometrical relationship is suggested to solve the inverse kinematics of the Reclaimer with redundancy. The proposed method was successfully applied to a working Reclaimer. An autonomous Reclaimer is now being operated in the yards of Kwangyang Steelworks in Korea.

  • ICRA - Automatic landing method of a Reclaimer on the stockpile
    Proceedings of International Conference on Robotics and Automation, 1997
    Co-Authors: Chintae Choi, Hyunsik Ahn, Lee Kwan-hee, Kitae Shin
    Abstract:

    The huge Reclaimers in the raw ore yard are used to dig ore and transfer it to the blast furnaces. In this paper, an automatic landing method of the Reclaimer is proposed to develop an autonomous Reclaimer. A 3-dimensional range finder which consists of a 2-dimensional scanner and an additional joint was developed with laser radar concepts and is installed on the roof of the Reclaimer to detect the ore pile. A height map is obtained from the acquired range data for an ore pile and a contour map for the pile is obtained through some image processing steps. The optimal landing point in the contour line is determined so that an overload problem does not occur in the slewing operation and reclaiming efficiency is maximized. The algorithm for finding the landing point needs an inverse kinematics solution for the Reclaimer. The Reclaimer has a redundancy due to the rotating buckets at the end of the its boom. A constraint equation for solving the inverse kinematics of the Reclaimer is also derived by the geometrical relationship.

  • Inverse kinematics of a Reclaimer: redundancy and solution
    1997 IEEE International Conference on Systems Man and Cybernetics. Computational Cybernetics and Simulation, 1997
    Co-Authors: Chintae Choi, Kitae Shin
    Abstract:

    The huge Reclaimers in the raw ore yard are used to dig ore and transfer it to the blast furnaces. When the buckets of the Reclaimer land on the stockpile, a method for solving inverse kinematics of a Reclaimer is presented in this paper. To detect the shape of the pile, a 3-dimensional range finder which consists of a 2-dimensional scanner and an additional joint is developed with laser radar concepts. The kinematic configuration of the Reclaimer is different from that of the commercial robot. The Reclaimer has a redundancy due to the rotating buckets at the end of the its boom. A constraint equation for solving the inverse kinematics of the Reclaimer is also derived by the geometrical relationship. A numerical method is used to obtain the joint angle of the Reclaimer.

Kmita A. - One of the best experts on this subject based on the ideXlab platform.

  • Influence of Reclamation Process on the Ecological Quality of Reclaim Sand
    Sciendo, 2017
    Co-Authors: Dereń M., Łucarz M., Roczniak A., Kmita A.
    Abstract:

    In this article, there were presented results of research on influence of reclamation process on the ecological quality of reclaim sand with furan resin used in nonferrous foundry. The quality of reclaimed sand is mainly define by two group of chemical substances from elution of reclaimed sand: Dissolves Organic Carbon (DOC) and Total Dissolves Solids (TDS). Reclaimed sand used in test was prepared in experimental thermal Reclaimer and mechanical vibration Reclaimer REGMAS installed in Faculty of Foundry Engineering at University Of Science and Technology in Krakow. The reference point is molding sand shaking out and crumble in jaw crusher. Test of elution was made in accredited laboratory in Center For Research and Environmental Control in Katowice up to the standard with Dissolves Organic Carbon (DOC) - PN-EN 1484:1999; Total Dissolves Solids (TDS) - PN-EN 15216:2010. The standard for elution test is PN-EN 12457- 4:2006. Except that we were made loss of ignition test, to check how many resin was rest on sand grains

  • Reclaiming Ability of Spent Sands with Modified, Hydrated Sodium Silicate
    Sciendo, 2014
    Co-Authors: Kamińska J., Kmita A.
    Abstract:

    The presented in the paper investigations were aimed at the determination of the reclaimed material (obtained in the dry mechanical reclamation process) addition influence on properties of moulding sands with hydrated sodium silicate modified by colloidal suspension of zinc oxide nanoparticles in propanol. Nanoparticles originated from the thermal decomposition of alkaline zinc carbonate, were used. The results of the reclamation of the spent moulding sand with hydrated sodium silicate performed in the AT-2 testing Reclaimer are presented in the paper. Both, spent sands from the Floster S technology and from the technology with the modified water-glass were subjected to the reclamation processes. The following determinations of the reclaimed material were performed: pH reaction, acid demand, ignition loss and Na2O content. The obtained reclaim was used as a matrix component of moulding sands with water-glass in the Floster S technology, in which it constituted 60% and 50% of the sand matrix. The strength properties of the prepared moulding sands were determined (bending strength Rgu, tensile strength Rm u) after samples storing times: 1h, 2h, 4h and 24 hours

Kitae Shin - One of the best experts on this subject based on the ideXlab platform.

  • Automatic landing method of a Reclaimer on the stockpile
    IEEE Transactions on Systems Man and Cybernetics Part C (Applications and Reviews), 1999
    Co-Authors: Chintae Choi, Kitae Shin, Keum Shik Hong
    Abstract:

    Large excavation Reclaimers are used to dig ore and transfer it to the blast furnaces that refine the ore into pure metal form. The reclaiming job consists of two operations: (1) landing a Reclaimer bucket on the surface of a pile and (2) slewing its boom with rotating buckets to scoop the ore. An automatic landing method for choosing where to dig in a pile of raw ore is proposed to achieve autonomous reclaiming. The method comprises detecting the shape of a pile, extracting contour lines of the pile, obtaining the joint angles of the Reclaimer and determining an optimal landing point. A 3D range finder was developed with laser radar concepts to detect the shape and height of the ore pile. A series of image processing techniques for extracting the contour line from the 3D range data of a pile is suggested. A height map is obtained from the acquired range data for a pile and a contour map is obtained through image processing steps, including interpolation and edge following. The optimal landing point of the bucket on the contour line is determined so that an overload problem does not occur in the slewing operation and the reclaiming efficiency can be maximized. The algorithm for finding the landing point requires an inverse kinematics solution for the Reclaimer. The forward kinematics of the Reclaimer is first obtained. A constraint equation based on the geometrical relationship is suggested to solve the inverse kinematics of the Reclaimer with redundancy. The proposed method was successfully applied to a working Reclaimer. An autonomous Reclaimer is now being operated in the yards of Kwangyang Steelworks in Korea.

  • ICRA - Automatic landing method of a Reclaimer on the stockpile
    Proceedings of International Conference on Robotics and Automation, 1997
    Co-Authors: Chintae Choi, Hyunsik Ahn, Lee Kwan-hee, Kitae Shin
    Abstract:

    The huge Reclaimers in the raw ore yard are used to dig ore and transfer it to the blast furnaces. In this paper, an automatic landing method of the Reclaimer is proposed to develop an autonomous Reclaimer. A 3-dimensional range finder which consists of a 2-dimensional scanner and an additional joint was developed with laser radar concepts and is installed on the roof of the Reclaimer to detect the ore pile. A height map is obtained from the acquired range data for an ore pile and a contour map for the pile is obtained through some image processing steps. The optimal landing point in the contour line is determined so that an overload problem does not occur in the slewing operation and reclaiming efficiency is maximized. The algorithm for finding the landing point needs an inverse kinematics solution for the Reclaimer. The Reclaimer has a redundancy due to the rotating buckets at the end of the its boom. A constraint equation for solving the inverse kinematics of the Reclaimer is also derived by the geometrical relationship.

  • Inverse kinematics of a Reclaimer: redundancy and solution
    1997 IEEE International Conference on Systems Man and Cybernetics. Computational Cybernetics and Simulation, 1997
    Co-Authors: Chintae Choi, Kitae Shin
    Abstract:

    The huge Reclaimers in the raw ore yard are used to dig ore and transfer it to the blast furnaces. When the buckets of the Reclaimer land on the stockpile, a method for solving inverse kinematics of a Reclaimer is presented in this paper. To detect the shape of the pile, a 3-dimensional range finder which consists of a 2-dimensional scanner and an additional joint is developed with laser radar concepts. The kinematic configuration of the Reclaimer is different from that of the commercial robot. The Reclaimer has a redundancy due to the rotating buckets at the end of the its boom. A constraint equation for solving the inverse kinematics of the Reclaimer is also derived by the geometrical relationship. A numerical method is used to obtain the joint angle of the Reclaimer.