• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.10
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• pp.712-719
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• 2019

This paper explores an implementation of finite element analysis and experiment in the design process of a tape spring hinge used for various CubeSat missions. Tape spring hinges consist of short-length hardened-steel strips with one-sided curvature, and thus the behavior is subject to large deformation with unpredicted non-linearity. Precise dimensions of a commercial tape spring are traced by the use of high-resolution digital camera, and thin-shell FEM analysis is conducted using ABAQUS program. Based on the rotation-moment analysis suggested in previous studies, parametric analysis is conducted by adjusting the contributing factors such as strip thickness and the subtended angle of the cross section. Finally the behaviors are investigated by both analytical and non-linear finite element methods, and the results are compared with the simple measurements. Further studies suggest a possible application in dynamic characteristics of hinges during CubeSat operations.

• Journal of KSNVE
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• v.3 no.4
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• pp.325-330
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• 1993

The longitudinal vibration of the tape in the tape transport system influences the performance of the nagnetic tape-recording system. Generally it is controlled by a passive method with impedance roller which is easy to implement and cost-effective. Therefore the effect of the impedance roller in reducing the tape vibration was analyzed in this paper. The practical tape transport system was modelled mathematically as a mass-spring system. Both simulation and experimental study were carried out in order to show the vibration reduction effect of the impedance roller.

• Composites Research
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• v.34 no.4
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• pp.226-232
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• 2021

In this paper, development of tape-springs made of composite materials was conducted for the deployment structures along with design, analysis, fabrication, and numerical and experimental investigation of mechanical behavior of the tape-springs. To this end, the tape-springs were manufactured according to three stacking patterns, and numerical and experimental investigation were conducted to determine whether or not they were damaged during bending with various selected composite materials. Finally, optimal stacking patterns that do not cause damage were selected during bending. With this information, the four-point bending test was conducted to obtain the moment-rotation curves. From results, it was confirmed that the nonlinear hysteresis phenomenon of the tape-springs was properly realized according to folding and unfolding. Therefore, it was confirmed that the composite material tape spring was properly developed.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.09a
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• pp.21-30
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• 2002

According the difference of flex substrate, (reel tape), there are three kind assembly types of LCD driver IC is COG, TCP and COF, respectively. The TCP is the maturest in these types for stability of raw material supply and other specification. And TCP is the major assembly type of LCD driver IC and the huge demand from Taiwan's large TFT LCD panel house since this spring. But due to its package structure and the raw material applied in this package, there is some limitation in fine pitch application of this package type, (TCP). So, COF will be very potential in compact and portable application comparison with TCP in the future. There are three kinds assembly methods in COF, one is ACF by using the anisotropic conductive film to connect the copper lead of tape and gold bump of IC, another is eutectic bonding by using the thermo-pressure to joint the copper lead of tape and gold bump of IC, and last is NCP by using non-conductive paste to adhere the copper lead of tape and gold bump of IC. To have a global realization, this paper will briefly review the status of Taiwan's large TFT panel house, the internal driver IC design house, and the back-end assembly house in the beginning. The different material property of raw material, PI tape is also compared in the paper. The more detail of three kinds of COF assembly method will be described and compared in this paper.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.7
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• pp.583-591
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• 2018

In this paper, we propose a new deployment test equipment that is characterized for the deployment test of single large solar panel with tape spring hinge. To perform the deployment test on ground, a device that takes gravity compensation into account should be used to create a zero gravity environment similar to that in orbit. We analyzed the advantages and disadvantages of the most commonly used deployment test equipment in the past through simple conceptual design, analysis, and tests to judge whether it is applicable to the deployment of the solar panel to be tested. A dummy frame was proposed to reduce the air drag effect during on-ground test and a self-aligning ball bearing and adjusting screws were applied to the deployment test equipment to solve the alignment problem with the gravity axis. And a horizontal bearing for radial movement applied to compensate for the change of the axis of the tape spring hinge. From these, we solved the problems of the conventional deployment test equipment by developing and verifying the new deployment test equipment characterized for the solar panel to be deployed in this paper.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.3
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• pp.289-296
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• 1996

Effects of crustal species on the characteristics of ambient particles were studied by applying a gas-particle equilibrium model, SCAPE, to the measurements at Kosan, Cheju Island during the spring and summer, 1994. Two cases were simulated; the measured composition was used without any modification (case 1), and the metal ion concentrations originated from crust were subtracted from the measured particle composition (case 2). Total suspended particles (TSPs) were collected by an automatic high volume tape sampler during spring period and by high volume samplers during summer period. The fine particles, PM 2.5, and gaseous volatile species were collected using a filter pack smapler during summer period. The water soluble ion concentrations were analyzed from all the particle samples. According to the simulation results, the effect of crustal elements on the chemical composition of particles is negligible for both TSP particles and PM 2.5 particles. Acidity of particles measured at Kosan, however, is affected by the change of the concentrations of crustal species, stronger effects for TSP particles than for PM 2.5 particles during summer, and stronger effects during summer than spring for TSP particle. The average pH decrease due to the absence of crustal species was about 0.10 for PM 2.5 particle during summer and 1.51 and 0.85 for TSP particles during summer spring, respectively. Water contents of PM 2.5 particles for both cases are comparable to each other. Estimated water content of TSP particles for case 2 is higher than that for case 1 by about 4 $\sim 6 \mum/m^3$ because salts of metal ions are not hygroscopic.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.E4
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• pp.177-186
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• 2003

The total of 1,454 aerosol samples were collected by high volume tape sampler at the Gosan Site in Jeju Island from 1992 to 1999, and the major water-soluble ionic components were chemically analyzed. The mean concentrations of nss-S $O_4$$^{2-}$, N $H_4$$^{＋}$, and N $O_3$$^{[-10]}$ showed high values, which were 6.73, 1.45, and 1.45 ${\mu}{\textrm}{m}$/㎥, respectively, while $Ca^{2+}$ and $K^{+}$ concentrations were low with the values of 0.49 and 0.42 $\mu\textrm{g}$/㎥. The concentrations of most components increased in spring but decreased in summer, especially with the remarkable increase of $Ca^{2+}$ and N $O_3$$^{[-10]}$ concentrations in spring. The seasonal comparison of nss-S $O_4$$^{2-}$ concentrations showed higher values with the order of spring > fall 〉 winter〉 summer, but spring 〉 winter〉 fall 〉 summer for N $O_3$$^{[-10]}$ Meanwhile, the concentration levels of N $a^{+}$ and C $l^{[-10]}$ increased more in winter season. According to the investigation of wind direction effect, the concentrations of most aerosol ionic components showed higher values consistently at the westerly and northerly wind conditions. Based on the factor analysis, the atmospheric aerosols in the Gosan Site are considered to be largely affected by marine sources, followed by anthropogenic and soil sources.urces..

• International journal of advanced smart convergence
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• v.12 no.2
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• pp.76-83
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• 2023

Squatting of agricultural work can cause musculoskeletal disorders due to excessive pressure and rotational force on the knee joint In order to improve the assistive chair used in squatting agricultural work so that it can be used in a narrow groove, it is intended to improve the musculoskeletal harm of squatting work by attaching a spring on the assistive chair. Therefore, in the presenty study, 3D drawing was done using ProEngineer (3D), and a mock-up was produced and tested. Using pro-Engineer, it was judged that it was rare for plastic to be broken by a spring, so the analysis was conducted with a focus on springs. It was found that the structure that can absorb the shock according to the rigidity of the tape spring and balance the body is that the power to withstand the load of the weight is distributed as a whole when five springs are used. Electromyography was measured using ME600 (Mega Electronics, Finland) Measuring equipment attached to the waist, thighs, calves, and shins. EMG values were measured and compared with the prototype in two ways, when the worker did not wear the product and when he wore an existing product on the market. As a result of the experiment when using the prototype, the maximum EMG value for each part is considered to be helpful in preventing musculoskeletal diseases as the amount of muscle used is reduced in the waist, thighs, calves, and shins.

• Journal of Korean Society for Atmospheric Environment
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• v.11 no.3
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• pp.245-252
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• 1995

Atmospheric aerosols were collected by a High Volume Tape Sampler from March 1992 to December 1993 ar Korean, Cheju, Korea. The water soluble ion concentrations in aerosol were analyzed. The concentrations of cations (N $a^{+}$, $K^{+}$, $Ca^{2+}$, $Mg^{2+}$, N $H_{4}$$^{+}$) were determined by an Inductively Coupled Plazma(ICP) or an Atomic Absorption Spectrometer(AAS), and those of anions (C $l^{[-10]}$ , N $O_{3}$$^{[-10]}$ , S $O_{4}$$^{2-}$) were analayzed by the capillary electrophoresis method. The $Ca^{2+}$, S $O_{4}$$^{2-}$ and N $O_{3}$$^{[-10]}$ concentrations in spring were higher than those in other seasons. The lowest concentrations of these elements were found in summer, largely due to scavenging by frequent rains. Especially the $Ca^{2+}$ concentration on April was three to four times higher than the annual mean concentration. The enrichment factor(E.F.) of each element was calculated. The annual mean E.F. values of the $Ca^{2+}$, $Mg^{2+}$ and C $l^{[-10]}$ in 1992 were the same as those in 1993 except $k^{+}$ and S $O_{4}$$^{2-}$. The correlation formula between all cations and anions for the whole period was Anions = 0.759 * Cations + 0.066.Cations + 0.066.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.1
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• pp.63-70
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• 2017

In this paper, we design and fabricate a de-orbiter using drag-sail and evaluate deployment characteristics. Without employing an actuator to deploy, the de-orbiter is activated by the SMA wire based the release mechanism and driven by the restoring force of the tape-spring. For efficient storage and deployment of drag-sail, an origami method of original ISO flasher is chosen and low priced mylar film is used as the material of the drag-sail. In addition, through the fault tree analysis method which is one of the one-shot device reliability evaluation methods, we confirm the reliability of the de-orbiter(0.997572) and the Roller failure has the highest criticality. Finally, we find feasibility of the proposed de-orbiter through the deployment demonstration of drag-sail.