• The Journal of the Convergence on Culture Technology
• /
• v.9 no.6
• /
• pp.919-925
• /
• 2023

Modern drones are equipped with miniaturized mission equipment capable of performing various tasks such as surveillance and reconnaissance. Consequently, these mission equipment are exposed to disturbances like wind loads and motor rotations, which can lead to instability in the operation of the Electro-Optical Targeting System (EOTS). Specifically, simple step inputs for changing the line of sight in EOTS can cause abrupt changes in speed, inducing overshoot and potentially creating instability along with other disturbances. To address this, a velocity profile was designed so that the angular velocity moves in a trapezoidal shape when changing the EOTS line of sight. A Double-loop controller was designed to apply this profile as an input to the external loop receiving position feedback. The system's stability was then compared, and the velocity profile was optimized within a stable range by varying maximum speed and acceleration.

• The Journal of the Korea Contents Association
• /
• v.17 no.6
• /
• pp.1-8
• /
• 2017

A smart leveling equipment was developed in this study by improving present leveling equipment. Both hardware and software of the equipment was developed and several accuracy tests of bench mark were conducted using various survey equipments. National control point (UO992-A), control points (15-00-06-24)-B and (15-00-06-23)-C were used for the accuracy test. As a result, the stable results in the range of errors were obtained in the cases of auto-level and digital level. Approximately 24mm error in the section of A-B and 26mm of B-C section was occurred in Smart Level equipment. This is due to the lack of technology completion and errors via relatively many numbers of installation tests. 46mm error of RMSE of smart level survey was occurred through the difference of section test. A small error was detected in short range but errors were accumulated far from the bench mark. It's concluded that an in-depth study emphasizing accuracy improvement can be practically applied to the various areas of industry.

• Journal of Advanced Navigation Technology
• /
• v.19 no.6
• /
• pp.473-483
• /
• 2015

This paper reports the single-input-single-output cascade control by using 1-axis attitude control test-bench for quad-rotor UAV. The test-bench was designed as a see-saw shape using 2 motors and propellers, and to enable changing the center of gravity with the center of gyration using ballast. The experiment was carried out by constructing a PID-PID controller having a cascade structure with the test-bench. The SIMC based PID gain tuning process, which makes PID gain tuning easy, was grafted to cascade control. To graft SIMC method, the system parameter estimation result was conducted with second order time delay model by using Matlab-Simulink. Gain tuning was conducted by simulating with estimated system parameter. In this paper, the conventional application of SIMC was conducted and improved application was proposed for improving stability at tuning process.

• Journal of the Korea Convergence Society
• /
• v.9 no.10
• /
• pp.257-263
• /
• 2018

The purpose of this study is to develop an automatic inspection system for a part of the differential drive gear into the transmission. This technology will make using the microvision automatic test equipment and automatic test equipment microlaser. This is that the operator intends to make the defect rate 0 in the inspection stage of the product which has been carelessly processed. The equipment developed in this research project will be applied to many areas. Packaging companies, nut bolt processing company, precisely supplier for printing on top of the semiconductor, SMT, etc. The company wants to sell the vision inspection equipment for various applications. If the defective rate of 0 is achieved through this research project, it is also possible to secure a stable supply from the parent company, and to lay the foundations for exporting based on product reliability. When the automatic inspection system is applied to domestic automobile parts processing companies, the reliability of automobiles in Korea will be greatly increased.

• Journal of Astronomy and Space Sciences
• /
• v.14 no.2
• /
• pp.259-268
• /
• 1997

We present the development process of a prototype CCD imaging system which is being built at Korea Astronomy Observatory(KAO) for astronomical applications. The CCD imaging system requires very low noise and high stability characteristics and is widely used for astronomical purposes from infrared to ultraviolet wavelength regions. However its system design, particularly for the controller design technique, as heart of the system, is not secured in Korea so far. The prototype electronics developed in this study consists of a signal chip controller which was implemented in an EPLD(Erasable Programable Logic Device) and an analog driver, a video processor with a LN2 cooling cryostat. A PC system was employed to control the whole system and to store the image data considering compatibility of the system. We have successfully obtained the first image in the laboratory with the prototype of this imaging system, and an image of the M15 at Sobaeksan Astronomy Observatory.

• Journal of Korea Society of Industrial Information Systems
• /
• v.20 no.5
• /
• pp.1-11
• /
• 2015

This paper is focused on how the trajectory of launch vehicle could be optimally estimated by the quadratic regression of trajectory data mining for the operation of telemetry ground system in NARO space center during real-time. To receive the telemetry data, the telemetry ground system has to track the space launch vehicle without tracking loss, and it is possible by the well-designed algorithm to estimate a flight position in real-time. For this reason, the quadratic regression model instead of interpolation was considered to estimate the exact position data of launch vehicle and the improvement of antenna performance. For analysis, the real trajectory data which had been logged during NARO 1st launch mission were used, the estimation result of launcher current position was analyzed by the mathematical modeling. In conclusion, the algorithm using quadratic regression based on trajectory data mining showed the better performance than previous interpolation algorithm to estimate the next flight position and the antenna driving performance.

• Journal of Digital Convergence
• /
• v.15 no.7
• /
• pp.223-229
• /
• 2017

Europe, the US and Japan have acquired test results on impact coefficient for a long time and applied it to equipment design to secure safety of structures. However, Korean enterprises use the impact factor held by advanced business to design equipment as it is difficult for them to obtain it through tests. In this paper, NX/NASTRAN, was used to perform static load analysis and impact load analysis of a PCB Handler, semiconductor test equipment, and the result was employed to study how to calculate the impact coefficient with the finite element analysis. The calculation method was applied to the JIS(Japanese Industrial Standard), and the impact coefficient of the PCB handler was calculated as 1.27 for the sudden start or stop. The impact coefficient generated by the analysis is expected to make a great contribution to the industry as it can be used to improve the equipment structure and develop on existing equipment in the future.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.41 no.4
• /
• pp.285-291
• /
• 2017

In this study, a case analysis for thermal design of electronic equipment using a phase change material(PCM) was performed numerically using ANSYS Fluent. Experiments were conducted to find the temperature increase(${\Delta}T_m$), melting temperature($T_m$), and volume expansion of the PCM under the melting process. To verify the accuracy of the Fluent solver model, $T_m$, ${\Delta}T_m$, and the melting time were compared with experimental results. To simulate the temperature stagnation phenomenon under the melting process, the equivalent specific heat method was applied to calculate the thermal properties of the PCM in the solver model. To determine the thermal stability of electronic equipment, we paid special attention to finding a thermal design for the PCM using fins. Further, an additional numerical analysis is currently underway to find an optimum design.

• Aerospace Engineering and Technology
• /
• v.7 no.1
• /
• pp.229-235
• /
• 2008

The ground flight termination system(GFTS) could be used for the termination of launch vehicle in flight motion when the launch vehicle deviates from the designated route due to the system malfunction or failure as well as the launch vehicle can't be tracked by the ground tracking system. This paper introduces the basic concept and design of the ground flight termination system to be used for KSLV launch mission in NARO space center. In order to design the optimal ground flight termination system for KSLV launch application, the operational concept reflected on the flight trajectory and system characteristics of KSLV launch vehicle should be considered. Moreover the RF link budget analysis, and the analysis for system availability and reliability are done. Based on the analysis above, the each subsystem of ground flight termination to transmit the termination signal in stable is designed for KSLV launch mission.

• Journal of the Society of Disaster Information
• /
• v.18 no.4
• /
• pp.699-705
• /
• 2022

Purpose: Sequence control is widely used by being applied to manufacturing, distribution, construction, and automation in the medical industry. With the development of the fourth industry, artificial intelligence convergence technology in the control field is becoming an important factor in the industry. In particular, it is required to evaluate the safety and innovation of facilities where microprocessors and artificial intelligence are fused to existing systems and develop reliable equipment, so it is intended to develop equipment for educational purposes and drive the development of the field. Method: The self-developed all-in-one artificial intelligence controller module is a device that combines artificial intelligence capabilities with existing sequence and PLC control circuits. As the performance evaluation items of this equipment, the recognition ability of motion, voice, text, color, etc. and the stability and reliability of the circuit were evaluated. Conclusion: After designing the sequence and PLC circuit, the performance evaluation items of the integrated integrated artificial intelligence controller module were all satisfied, and there was no problem in the safety and reliability of the circuit.