The Experts below are selected from a list of 10620 Experts worldwide ranked by ideXlab platform
Akinori Saito - One of the best experts on this subject based on the ideXlab platform.
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a strategy for identifying static deviations in universal spindle head type multi axis Machining Centers
International Journal of Machine Tools & Manufacture, 2006Co-Authors: K. M Muditha Dassanayake, Masaomi Tsutsumi, Akinori SaitoAbstract:This research was conducted in order to investigate the effectiveness of the checking method specified in ISO 10791-6 and to propose an additional method for identifying the geometric deviations inherent to five-axis Machining Centers with a universal spindle head. The specified method is not sufficient for assessing the influence of individual geometric deviations. Therefore, additional measurements are needed in order to use this checking method effectively. The spherical motion in the additional measurements is a modified version of the ISO standard. Some of the deviations are presumed based on the result of the additional measurements, and so the method of identifying the remainder of the geometric deviations was designed by analyzing the link geometry of the machine. The identification procedure consists of three steps. In the first and second steps, after performing two measurements, six out of ten deviations are identified by means of an observation equation. In the third step, four of the ten deviations are identified by means of the link geometry. The exactness of the proposed procedure for identifying the deviations inherent to the five-axis machine is confirmed through simulations.
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A strategy for identifying static deviations in universal spindle head type multi-axis Machining Centers
International Journal of Machine Tools and Manufacture, 2006Co-Authors: K. M Muditha Dassanayake, Masahiro Tsutsumi, Akinori SaitoAbstract:This research was conducted in order to investigate the effectiveness of the checking method specified in ISO 10791-6 and to propose an additional method for identifying the geometric deviations inherent to five-axis Machining Centers with a universal spindle head. The specified method is not sufficient for assessing the influence of individual geometric deviations. Therefore, additional measurements are needed in order to use this checking method effectively. The spherical motion in the additional measurements is a modified version of the ISO standard. Some of the deviations are presumed based on the result of the additional measurements, and so the method of identifying the remainder of the geometric deviations was designed by analyzing the link geometry of the machine. The identification procedure consists of three steps. In the first and second steps, after performing two measurements, six out of ten deviations are identified by means of an observation equation. In the third step, four of the ten deviations are identified by means of the link geometry. The exactness of the proposed procedure for identifying the deviations inherent to the five-axis machine is confirmed through simulations. ?? 2005 Elsevier Ltd. All rights reserved.
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identification of angular and positional deviations inherent to 5 axis Machining Centers with a tilting rotary table by simultaneous four axis control movements
International Journal of Machine Tools & Manufacture, 2004Co-Authors: Masaomi Tsutsumi, Akinori SaitoAbstract:This paper describes a method for identifying the eight deviations inherent to five axis control Machining Centers by means of simultaneous four-axis control movements. Some methods to identify the deviations have been proposed. However, a simultaneous four-axis control technique using a ball bar instrument has not been applied to the measurement of relative displacements between the main spindle and the worktable. Furthermore, the method for assessing the deviations from the trajectories has not been proposed. Thus, in this paper, a calibration method based on the simultaneous four-axis control technique is proposed for five axis control Machining Centers with a tilting rotary table. To confirm the validity of the proposed method, simulations were conducted. The trajectories were obtained by means of a mathematical model into which the eight deviations were substituted. In the first step, four of the eight deviations were estimated by an observation equation for which two measurement trajectories and six reference ones were used. In the second step, the remaining four deviations were geometrically calculated using the values estimated by the observation equation. As a result, it was found that the proposed method was sufficient to identify the deviations accurately.
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identification and compensation of systematic deviations particular to 5 axis Machining Centers
International Journal of Machine Tools & Manufacture, 2003Co-Authors: Masaomi Tsutsumi, Akinori SaitoAbstract:Abstract This paper presents an algorithm for identifying particular deviations such as angular deviations around linear axes relating to rotary axes in 5-axis Machining Centers. In this study, three kinds of simultaneous three-axis control motions are designed for each rotary axis to identify the deviations. In the measurement, two translational axes and one rotary axis are simultaneously controlled keeping the distance between a tool and a worktable constant. Telescoping ball bar is an effective instrument for measuring the relative displacement to the reference length in the work volume because its attitude is freely changed. In these three-axis control motions, the sensitive direction of the ball bar is kept constant. In order to determine the deviations, we derive eight equations from the relationship between the eccentricities obtained from the measured circular trajectories and the approximations derived from the mathematical model based on the simulation. In the simulation, a mathematical model considering the particular deviations is developed and then the characteristic diagrams are prepared for every deviation and every three-axis control motion. Based on the results, we propose a procedure for identifying the particular deviations in 5-axis Machining Centers and its procedure has been applied to identify the deviations actually. From both the simulation and the experiment, it has been confirmed that the proposed method gives precision results and is able to apply to the measurement of 5-axis Machining center which is a tilting rotary table type.
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Development of Calibration Methods of 5-axis Controlled Machining Centers (3rd Report)-Measurement Methods for Various Structural Configurations of 5-axis Controlled Machining Centers-
Journal of The Japan Society for Precision Engineering, 2003Co-Authors: Akinori Saito, Masaomi Tsutsumi, Shigetaka Mikami, Souvannavong SisavathAbstract:In this paper, the structural configurations of 5-axis Machining Centers are researched, and a proposed method is applied to the measurement of the geometric deviations of the available machines, and the effectiveness of the method is discussed. The structural configurations of the 5-axis Machining Centers are divided into three types. The ball-bar technique is applied to the measurement of simultaneous 4-axis control motion, and the error motion is simulated using the motion analysis software. As the results, the geometric deviations in three types of 5-axis Machining Centers can be estimated by the proposed method. 5-axis control motion using a simplejig is proposed as alternative measurement method, and it is found that the proposed method is effective to evaluate the geometric deviations as well as 4-axis control motion.
Masaomi Tsutsumi - One of the best experts on this subject based on the ideXlab platform.
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enhancement of geometric accuracy of five axis Machining Centers based on identification and compensation of geometric deviations
International Journal of Machine Tools & Manufacture, 2013Co-Authors: Masaomi Tsutsumi, Noriyuki Kato, Shintaro Tone, Ryuta SatoAbstract:Abstract The present paper describes the enhancement of kinematic accuracy of five-axis Machining Centers with a tilting rotary table. Geometric deviations inherent to the five-axis machine are calibrated through the actual trajectories measured by two different settings of a ball bar in simultaneous three axis motion. Measurement using a cylindrical coordinate system is superior to measurement using a Cartesian coordinate system from the viewpoint of the number of measurements. In order to verify the effectiveness of the calibration method, the inherent geometric deviations measured on the cylindrical coordinate system were corrected through the post processing of NC data for cutting the cone-frustum. The relative displacement between the tool center point and the workpiece was detected by the ball bar. Based on the experimental results, it is confirmed that the radius, center position, and roundness of the three-dimensional circular trajectory are improved when the inherent geometric deviations are corrected.
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proposal of a Machining test of five axis Machining Centers using a truncated square pyramid
Key Engineering Materials, 2012Co-Authors: Katsunori Ohta, Zhi Meng Li, Masaomi TsutsumiAbstract:NAS 979 has been used for over 40 years as a performance evaluation standard for five-axis Machining Centers. This standard provides some finishing conditions of the cone-frustum under five-axis control, and prescribes the measuring methods and permissible tolerances of geometric deviations. However, this standard cannot be applied to the tilting rotary table type five-axis Machining center but to the universal spindle head type one. When the standard is applied to the tilting rotary table type, it is not clear yet that the effects of the geometric and synchronous deviations which influence the measured results. Thus, there are no methods for evaluating the accuracy of linear interpolation movement under simultaneous five-axis control. This paper proposes a Machining test method using a truncated square pyramid for checking the accuracy of the tilting rotary table type five-axis Machining Centers. In the simulation and experiment, the bottom of the truncated square pyramid with a half apex angle of 15° is mounted on a fixture with a slope of 10° or 20°, and feed velocity of each axis is analyzed by changing the center position.
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3d circular interpolation motion equivalent to cone frustum cutting in five axis Machining Centers and its sensitivity analysis
Procedia CIRP, 2012Co-Authors: Noriyuki Kato, Ryuta Sato, Masaomi TsutsumiAbstract:Abstract The present paper describes a testing method for five-axis Machining Centers using three-dimensional circular interpolation movement equivalent to cone-frustum cutting. In the present paper, the test conditions, such as the half apex angle of cone-frustum and the sensitive directions of the ball bar device were investigated. In addition, the sensitivity coefficient of each axis was investigated. It is found from the analysis of the sensitivity coefficient that the trajectory due to the errors of the axis of rotation is strongly affected by the sensitive direction of the ball bar for the case of a half apex angle of 45°
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compensation of quadrant glitches with two peaks in circular motions of Machining Centers
Transactions of the Japan Society of Mechanical Engineers. C, 2012Co-Authors: Takuro Higuchi, Ryuta Sato, Hiromichi Kunisada, Yoshinori Kunii, Masaomi TsutsumiAbstract:Quadrant glitches are one of the causes of deteriorating the Machining accuracy in NC machine tools because those leave streaky marks on the machined surfaces. The quadrant glitch is caused by friction of the ball screw and linear guides of feed drive systems. In this study, when the circular trajectories are precisely investigated by conducting the circular motions under various conditions, it is found that the preload in the ball screw affects the height and shape quadrant glitches at low feed speed. It is caused by the difference of contact points between balls and grooves of ball screws. It is also found that the quadrant glitch becomes one peak in case of oversize preload in ball screw, and two peaks in case of offset preload. In this study, a method for compensating two peaks observed in quadrant glitches due to the change of contact points between balls and grooves of a ball screw is proposed. A proposed compensating method can cancel the friction torque changes generated in the ball screws with a new mathematical model. It is confirmed that the proposed method can decrease the quadrant glitches in a wide feed speed range through simulation and experiment, and the proposed method can correct two peaks of the quadrant glitches in high accuracy. In addition, from circular motions with mass, it is confirmed that the proposed method can correct the quadrant glitches without deteriorating effect of mass.
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evaluation of synchronous motion in five axis Machining Centers with a tilting rotary table
Journal of Advanced Mechanical Design Systems and Manufacturing, 2007Co-Authors: Masaomi Tsutsumi, Daisuke Yumiza, Keizo Utsumi, Ryuta SatoAbstract:This paper proposes a new method for evaluating the synchronous inaccuracy of a translational axis and a rotational axis in five-axis controlled Machining Centers with a tilting rotary table. A circular trajectory whose shape is easy to evaluate the specific features is adopted for measuring the circular path described by the two axes. The influence of inaccurate synchronization on the circular path was simulated by changing the distance between the Centers of the rotary table and the circular path, the radius of the circular path and the feed speed. Measurement conditions were determined based on the simulation results, and then ball bar measurements and Machining experiments were conducted. From the simulation and experimental results, it is confirmed that the proposed method can be used for evaluating the inaccurate synchronization of a translational axis and a rotational axis. However, careful alignment of the center of the rotational axis and the machine coordinate origin is important for evaluating the synchronous accuracy. The ratio of the distance between both Centers of the rotational axis and the circular path to the radius provides useful information for the evaluation.
K. M Muditha Dassanayake - One of the best experts on this subject based on the ideXlab platform.
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a strategy for identifying static deviations in universal spindle head type multi axis Machining Centers
International Journal of Machine Tools & Manufacture, 2006Co-Authors: K. M Muditha Dassanayake, Masaomi Tsutsumi, Akinori SaitoAbstract:This research was conducted in order to investigate the effectiveness of the checking method specified in ISO 10791-6 and to propose an additional method for identifying the geometric deviations inherent to five-axis Machining Centers with a universal spindle head. The specified method is not sufficient for assessing the influence of individual geometric deviations. Therefore, additional measurements are needed in order to use this checking method effectively. The spherical motion in the additional measurements is a modified version of the ISO standard. Some of the deviations are presumed based on the result of the additional measurements, and so the method of identifying the remainder of the geometric deviations was designed by analyzing the link geometry of the machine. The identification procedure consists of three steps. In the first and second steps, after performing two measurements, six out of ten deviations are identified by means of an observation equation. In the third step, four of the ten deviations are identified by means of the link geometry. The exactness of the proposed procedure for identifying the deviations inherent to the five-axis machine is confirmed through simulations.
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A strategy for identifying static deviations in universal spindle head type multi-axis Machining Centers
International Journal of Machine Tools and Manufacture, 2006Co-Authors: K. M Muditha Dassanayake, Masahiro Tsutsumi, Akinori SaitoAbstract:This research was conducted in order to investigate the effectiveness of the checking method specified in ISO 10791-6 and to propose an additional method for identifying the geometric deviations inherent to five-axis Machining Centers with a universal spindle head. The specified method is not sufficient for assessing the influence of individual geometric deviations. Therefore, additional measurements are needed in order to use this checking method effectively. The spherical motion in the additional measurements is a modified version of the ISO standard. Some of the deviations are presumed based on the result of the additional measurements, and so the method of identifying the remainder of the geometric deviations was designed by analyzing the link geometry of the machine. The identification procedure consists of three steps. In the first and second steps, after performing two measurements, six out of ten deviations are identified by means of an observation equation. In the third step, four of the ten deviations are identified by means of the link geometry. The exactness of the proposed procedure for identifying the deviations inherent to the five-axis machine is confirmed through simulations. ?? 2005 Elsevier Ltd. All rights reserved.
Ryuta Sato - One of the best experts on this subject based on the ideXlab platform.
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workpiece setup simulation based on machinable space of five axis Machining Centers
Procedia CIRP, 2014Co-Authors: Mohammad Miradj Isnaini, Ryuta Sato, Keiichi ShiraseAbstract:Abstract An actual Machining center specification, e.g. the axes travel, the workpiece size allowance, etc., needs to be considered for constructing a Machining process plan. In this paper, a machinable space of a five-axis Machining center is proposed for simulating the workpiece setup. The machinable space is constructed by a table region and a tool cone. The tool cone is an allowance of the spindle diameter and the cutting tool length. By fitting in the visibility area from a total removal volume (TRV) of the Machining process plan, a TRV network can be established. The workpiece setup is estimated by positioning the TRV network within the table region. The positioning process can be used for estimating the number of setup changes on the corresponding machinable space.
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enhancement of geometric accuracy of five axis Machining Centers based on identification and compensation of geometric deviations
International Journal of Machine Tools & Manufacture, 2013Co-Authors: Masaomi Tsutsumi, Noriyuki Kato, Shintaro Tone, Ryuta SatoAbstract:Abstract The present paper describes the enhancement of kinematic accuracy of five-axis Machining Centers with a tilting rotary table. Geometric deviations inherent to the five-axis machine are calibrated through the actual trajectories measured by two different settings of a ball bar in simultaneous three axis motion. Measurement using a cylindrical coordinate system is superior to measurement using a Cartesian coordinate system from the viewpoint of the number of measurements. In order to verify the effectiveness of the calibration method, the inherent geometric deviations measured on the cylindrical coordinate system were corrected through the post processing of NC data for cutting the cone-frustum. The relative displacement between the tool center point and the workpiece was detected by the ball bar. Based on the experimental results, it is confirmed that the radius, center position, and roundness of the three-dimensional circular trajectory are improved when the inherent geometric deviations are corrected.
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3d circular interpolation motion equivalent to cone frustum cutting in five axis Machining Centers and its sensitivity analysis
Procedia CIRP, 2012Co-Authors: Noriyuki Kato, Ryuta Sato, Masaomi TsutsumiAbstract:Abstract The present paper describes a testing method for five-axis Machining Centers using three-dimensional circular interpolation movement equivalent to cone-frustum cutting. In the present paper, the test conditions, such as the half apex angle of cone-frustum and the sensitive directions of the ball bar device were investigated. In addition, the sensitivity coefficient of each axis was investigated. It is found from the analysis of the sensitivity coefficient that the trajectory due to the errors of the axis of rotation is strongly affected by the sensitive direction of the ball bar for the case of a half apex angle of 45°
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compensation of quadrant glitches with two peaks in circular motions of Machining Centers
Transactions of the Japan Society of Mechanical Engineers. C, 2012Co-Authors: Takuro Higuchi, Ryuta Sato, Hiromichi Kunisada, Yoshinori Kunii, Masaomi TsutsumiAbstract:Quadrant glitches are one of the causes of deteriorating the Machining accuracy in NC machine tools because those leave streaky marks on the machined surfaces. The quadrant glitch is caused by friction of the ball screw and linear guides of feed drive systems. In this study, when the circular trajectories are precisely investigated by conducting the circular motions under various conditions, it is found that the preload in the ball screw affects the height and shape quadrant glitches at low feed speed. It is caused by the difference of contact points between balls and grooves of ball screws. It is also found that the quadrant glitch becomes one peak in case of oversize preload in ball screw, and two peaks in case of offset preload. In this study, a method for compensating two peaks observed in quadrant glitches due to the change of contact points between balls and grooves of a ball screw is proposed. A proposed compensating method can cancel the friction torque changes generated in the ball screws with a new mathematical model. It is confirmed that the proposed method can decrease the quadrant glitches in a wide feed speed range through simulation and experiment, and the proposed method can correct two peaks of the quadrant glitches in high accuracy. In addition, from circular motions with mass, it is confirmed that the proposed method can correct the quadrant glitches without deteriorating effect of mass.
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evaluation of synchronous motion in five axis Machining Centers with a tilting rotary table
Journal of Advanced Mechanical Design Systems and Manufacturing, 2007Co-Authors: Masaomi Tsutsumi, Daisuke Yumiza, Keizo Utsumi, Ryuta SatoAbstract:This paper proposes a new method for evaluating the synchronous inaccuracy of a translational axis and a rotational axis in five-axis controlled Machining Centers with a tilting rotary table. A circular trajectory whose shape is easy to evaluate the specific features is adopted for measuring the circular path described by the two axes. The influence of inaccurate synchronization on the circular path was simulated by changing the distance between the Centers of the rotary table and the circular path, the radius of the circular path and the feed speed. Measurement conditions were determined based on the simulation results, and then ball bar measurements and Machining experiments were conducted. From the simulation and experimental results, it is confirmed that the proposed method can be used for evaluating the inaccurate synchronization of a translational axis and a rotational axis. However, careful alignment of the center of the rotational axis and the machine coordinate origin is important for evaluating the synchronous accuracy. The ratio of the distance between both Centers of the rotational axis and the circular path to the radius provides useful information for the evaluation.
Masahiro Tsutsumi - One of the best experts on this subject based on the ideXlab platform.
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A strategy for identifying static deviations in universal spindle head type multi-axis Machining Centers
International Journal of Machine Tools and Manufacture, 2006Co-Authors: K. M Muditha Dassanayake, Masahiro Tsutsumi, Akinori SaitoAbstract:This research was conducted in order to investigate the effectiveness of the checking method specified in ISO 10791-6 and to propose an additional method for identifying the geometric deviations inherent to five-axis Machining Centers with a universal spindle head. The specified method is not sufficient for assessing the influence of individual geometric deviations. Therefore, additional measurements are needed in order to use this checking method effectively. The spherical motion in the additional measurements is a modified version of the ISO standard. Some of the deviations are presumed based on the result of the additional measurements, and so the method of identifying the remainder of the geometric deviations was designed by analyzing the link geometry of the machine. The identification procedure consists of three steps. In the first and second steps, after performing two measurements, six out of ten deviations are identified by means of an observation equation. In the third step, four of the ten deviations are identified by means of the link geometry. The exactness of the proposed procedure for identifying the deviations inherent to the five-axis machine is confirmed through simulations. ?? 2005 Elsevier Ltd. All rights reserved.
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Reduction of run-out and vibration of high speed spindle for Machining Centers (1st Report) - Effectiveness of 3-plane balancing
Seimitsu Kogaku Kaishi Journal of the Japan Society for Precision Engineering, 2003Co-Authors: Futoshi Okumura, Masahiro TsutsumiAbstract:In this paper, a method for reducing the run-out and vibration of high speed spindles of Machining Centers is experimentally investigated. In the experiment, the run-out and vibration of a conventional spindle designed by one of authors have been measured by using two displacement sensors and a field balancer with two accelerometers. It is found from the experimental results that both of them can not be reduced at the same time. To overcome the problem, a new unit with a shorter spindle than the conventional one has been developed. The modified spindle unit was designed for high speed and high precision Machining Centers. This unit has three balancing planes to reduce the run-out and vibration due to the unbalance mass. Two balancing planes are arranged on both ends of spindle, and third one is arranged near to the rotor of motor between two support bearings. Using the modified . spindle unit, the run-out and vibration have been investigated. It is confirmed that the proposed method is useful to reduce the vibration and run-out at the same time. It is also found that a high speed spindle for Machining Centers should be considered as a flexible rotor system rather than a rigid one.
