• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.754-758
• /
• 1996

In this paper, a new method of position synchronizing control is proposed for multi-axes driving system. The proposed synchronizing control system is constituted with speed and synchronizing controller. The structure of synchronizing control system is varied by sign of synchronizing error. When a disturbance input becomes added to one axis, this axis becomes slave axis. The other axis is master axis. Therefore, master axis is not influenced by the disturbance. The speed controller of the first axis is designed by $H_{\infty}$ control theory. The speed controller of the second axis is designed by inverse dynamics of speed control system of the first axis. The speed control system designed with $H_{\infty}$ controller guarantees low sensitivity for the disturbance as well as robustness against model uncertainties. Especially, the synchronizing controller is designed to keep position error to minimize by controlling speed of slave axis. The effectiveness of the proposed method is successfully confirmed through several experiments.

• Composites Research
• /
• v.24 no.2
• /
• pp.14-21
• /
• 2011

In this paper, a dynamic model is proposed for multi-axis optical structure of an aircraft. Modal analysis, sine-wave analysis, and random vibration analysis are done using a multi-body dynamic program for the multi-axis optical structure. By applying Al 6061-T6 and two types of CFRP to the camera module, x, y, and z responses are found and compared according to each axis excitation. The results will be used for reducing the weight of the camera module.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.25 no.5
• /
• pp.313-320
• /
• 2016

The need for high-strength, multi-axis, and multi-functional machine tools has recently increased because of part complexity and workpiece strength. However, most of the machine tool manufacturers rely on experience for a detailed design because of the shortcomings in the existing design technology. This study uses a topology optimization method to more effectively design a large multi-functional machine tool considering static stiffness. The ram, saddle, and column parts are important structures in a machine tool. Hence, they are selected for the finite element method analysis. Based on this analysis, the optimized internal rib structure for those parts is designed for desirable rigidity and weight. This structure could possibly provide the required design technology for machine tool manufacturers.

• Proceedings of the KIPE Conference
• /
• 2000.07a
• /
• pp.641-644
• /
• 2000

Recently As the performance of the personal computer has been improving rapidly lots of research for the pc-based numerical computer actively progress in an easy repair maintenance and improving the performance with less cost. This paper presents the design using complex programmable logic device(CPLD). The CPU of Motion Controller that function as the real time control of the independent multi-axis motion the error-detect module and external I/O control made use of 80C196KC, In this paper The PC-NC effectively distributed to the load of NCK(numerical computer kernel) and have the advantage of high speed and precision.

• Proceedings of the KWS Conference
• /
• 2008.05a
• /
• pp.41-41
• /
• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1992.10a
• /
• pp.192-197
• /
• 1992

The position error in multi-axis machine tools are due to many elements, such as the static friction, servo lag, a nonlinear disturbance, the gain mismatch between multi-axis controllers. In the work, modeling for the plant was carried out through the velocity response by the step input signal. Digital PI controllers, LQ optimal controllers and feedforward controllers are designed for a high tracking performance based on the model. The results of experimentation showed that the controllers worked properly.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1994.10a
• /
• pp.336-342
• /
• 1994

This paper presents an useful technique for assessing the volumetric error in multi_axis machine tools using the kinematic double ball bar and 3 dimensional spherical contouring. The developed system proposes the 3 dimensional spherical contour for the error analysis. The developed system input the measured radial data, analysing the volumetric errors such as positional, strightness, angle, and squareness errors, etc. The developed system has been tested in a practical machine tool, and showed high

• Structural Engineering and Mechanics
• /
• v.38 no.6
• /
• pp.825-847
• /
• 2011

This paper investigates the design using wind-moment method for semi-rigid un-braced steel frames bending on weak axis. A limiting sway method has been proposed to reduce the frame sway. Allowance for steel section optimization between moment of inertia on minor axis column and major axis beam was used in conjunction with slope-deflection analysis to derive equations for optimum design in the proposed method. A series of un-braced steel frames comprised of two, four, and six bays ranging in height of two and four storey were studied on minor axis framing. The frames were designed for minimum gravity load in conjunction with maximum wind load and vice-versa. The accuracy of the design equation was found to be in good agreement with linear elastic computer analysis up to second order analysis. The study concluded that the adoption of wind-moment method and the proposed limiting sway method for semi-rigid steel frame bending on weak axis should be restricted to low-rise frames not more than four storey.

• Composites Research
• /
• v.36 no.5
• /
• pp.321-328
• /
• 2023

This study developed the in-situ stamp-forming process using the multi-axis robotic arm to fabricate thermal composite parts. Optimal fabrication parameters with the multi-axis robotic arm were determined using finite element analysis and these parameters were further refined through the practical manufacturing process. A comparison between the manufactured parts and finite element analysis results was conducted regarding thickness uniformity and wrinkle distribution to confirm the validity of the finite element analysis. Additionally, to evaluate the formability of the manufactured composite parts, measurements of crystallinity and porosity were taken. Consequently, this study establishes the feasibility of the In-situ stamp-forming consolidation using a robotic arm and verifies the potential for producing composite parts through this process.

• Journal of the Korean Society for Precision Engineering
• /
• v.29 no.2
• /
• pp.156-160
• /
• 2012

Recently, the demands of the large scale machine tools gradually increase to machine the large parts, such as large scale crankshaft, yaw and pitch bearings for the wind power generator and the vehicle or aircraft components. But the high technology is necessary in order to develop the huge machine tools. Furthermore, the global market of it has been monopolized by a few companies. So, we need to develop the large scale machine tools and study its core technology to rush into the increasing market. In this study, we carried out the researches for the important core technology of a multi-tasking, machine tool; a large scale 5-axis machine tool of gantry type for multi-task machining. This study is focused on the design of large size gantry type multi-axis machine. In the case of large size of machine the cross rail deflection in the X-axis is significant. To reduce the deflection due to the eccentric spindle head, a special hollow type design in the cross rail with outside ram is adapted in this study. Also, the Zig-Zag motion in the Y-axis is inevitable with the gantry geometry, which is by the un-balancing, different motion at the left and the right columns moving. We tried to reduce the influence of Zig-Zag motion using FEM with different loading conditions at the left and the right side column.