• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.1073-1077
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• 1996

This paper presents a recoil and counter recoil(R&CR) motion measurement method using linear variable differential transformers(LVDT). The output of a LVDT is obtained from the differential voltage of the 2nd transformers. As a sensor core is attached at the motion body, the output is directly proportional to the core motion. Displacement, velocity and acceleration are measure from the core length. With a comparison between the measurement result and the known value which is obtained by the precision steel tape, the accuracy and the usefulness of the proposed scheme is validated.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.5
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• pp.455-460
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• 1997

This paper presents a recoil and counter recoil motion measurement method using linear variable differential transformers(LVDT). The output of a LVDT is obtained from the differential voltage of the 2nd transformers. As the sensor core is attached to the motion body, the output is directly proportional to the core motion. Displacement, velocity and acceleration are measured from the core length. A comparison between the measurement result and the known value, which is obtained by the precision steel tape, shows that the accuracy and the usefulness of the proposed scheme is validated.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1380-1383
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• 1996

This paper presents a recoil and counter recoil(R&CR) motion measurement method using linear variable differential transformers(LVDT). The output of a LVDT is obtained from the differential voltage of the 2nd transformers. As a sensor core is attached at the motion body, the output is directly proportional to the core motion. Displacement, velocity and acceleration are measure from the core length. With a comparison between the measurement result and the known value which is obtained by the precision steel tape, the accuracy and the usefulness of the proposed scheme is validated.

• Journal of the Korean Magnetics Society
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• v.25 no.3
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• pp.83-86
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• 2015

Nowadays the weapon systems are employed air bursting munition (ABM) as smart programmable 40 mm shells which have been developed in order to hit the target with programmed munition that can be air burst after a set distance in the battlefield. In order to improve the accuracy of such a bursting time, by measuring the speed of the munition from the barrel, weapon systems calculate the exact time of flight to the target and then the time information must be inputted to the munition. In this study, we introduce a device capable of detecting a shot at K4 40 mm automatic grenade. The shot is composed of a rotating copper band to convert linear motion into rotary motion when it passes through the barrel, the steel section is exert the effect of fragment and aluminum section to give fuze information. The aluminum section was used to detect munition using eddy current method. To measure muzzle velocity by means of non-contact method, two eddy current probes separated 10 cm was employed. Time interval between two eddy current probe detection times was used as muzzle velocity. The eddy current probe was fabricated U-shape Mn-Zn ferrite core with enamelled copper wire, and 200 kHz alternating current was used to detect inductance change. Measured muzzle velocity using the developed sensor was compared to the Doppler radar system. The difference was smaller than 1%.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.2
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• pp.47-53
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• 2024

Purpose : This study investigated the effects of concentric and eccentric contractions on muscle strength using an isokinetic dynamometer (ID) in college students in their 20s. It aimed to understand the impact of differences between the dominant and non-dominant sides on strength asymmetry and to elucidate the clinical implications of these differences to establish an appropriate posture and environment for patients. Methods : The experiment was conducted with 30 healthy adult participants. Prior to the experiment, participants underwent a warm-up targeting the shoulders, and efforts were made to eliminate factors that could potentially influence the measurement results. Subsequently, the maximum safe range of motion of shoulder joint abduction, extension, and flexion was measured using an isokinetic muscle function testing device. Muscle strength was assessed using concentric and eccentric contractions alternating between the dominant and non-dominant sides, and paired sample t-tests were used for the analysis. Results : There was no significant difference between bilateral peak torques for eccentric contraction in shoulder joint abduction, extension, and flexion (p>0.05). There was also no significant difference between bilateral peak torques for concentric contraction in shoulder joint abduction, extension and flexion (p>0.05). Conclusion : This study found no statistically significant difference in muscle strength between the dominant and non-dominant sides during concentric and eccentric contractions. However, previous studies have shown significant differences between the dominant and non-dominant sides during eccentric and concentric contractions during internal shoulder rotation in the general population, as well as significant differences in the upper trapezius muscle. Therefore, further research is needed to support the application of different intensities for bilateral muscle strengthening exercises in clinical practice.