• Journal of the Korean Society for Precision Engineering
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• v.22 no.9 s.174
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• pp.147-154
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• 2005

A precision hi-directional actuator for a high precision leveling system with $Z{\Theta}_x{\Theta}_y$ motions is proposed and designed in this paper. The actuator is composed of a force generation structure, a guide mechanism, and a symmetric structure. At first, its driving force is generated by a change of flux in air gaps by permanent and changeable flux. The permanent flux is generated by a permanent magnet. The changeable flux is created by variable current flowing through coil. The combination of permanent and changeable flux makes various flux densities in air gaps between moving part and fixed yokes. And then, the difference between flux densities in lower and upper gaps creates forces fur the $bi-direction({\pm}z)$ motion. The guide mechanism of this actuator is composed of two circular plates and one shaft. Reducing motions generated by forces except z-motion, these circular plates endow the actuator with high stiffness for fast settling time. And the function of the shaft is to transfer motion to an object. At last, total body has a symmetric structure to be stable on thermal error. The actuator is designed by MAXWELL 2D and ProMECHANICA. The designed actuator is evaluated by 8nm laser doppler vibrometer, dynamic signal analyzer, and simple PID controller.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.9
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• pp.886-891
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• 2009

One of the important functions of prosthetic foot is the foot inversion-eversion which is so important when walking on uneven surfaces. The aim of our study was to evaluate the effect of foot eversion angle especially on knee and ankle joint for transtibial amputees by motion analysis. The experimental data were collected from three transtibial amputees and then ten healthy individuals. To simulate walking on side sloping ground, we used custom-made slope (5, 10, 15 degrees). Motion analysis was performed by 3-dimensional motion analyzer for 6 dynamic prosthetic feet. The results showed that knee abduction moments of amputated leg were decreased but those of sound leg were mainly increased as foot eversion angle increased. And ankle abduction moments of sound leg were inconsistent in magnitude and tendency between control and experimental group. Therefore foot eversioncharacteristics should be considered to develop advanced prosthetic foot.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.5
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• pp.1-6
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• 2007

This paper presents a new experimental Servo-Parameter tuning technique for a 6-axes articulated robot manipulator, especially considering robot's dynamics. First of all, investigation for proportional gain of velocity control loop by using a Dynamic Signal Analyzer(DSA) is performed. Using the FUNCTION characteristic of DSA based on the Bode plot, the Bode plot of open loop transfer function can be obtained. In turn, the integral gain of a servo controller can be found out by using the integration time constant extracted from the Bode plot of open loop transfer function. In the meanwhile, the positional gain of the servo controller can be obtained by using the Bode plot of the closed loop transfer function. Using the experimental gain tuning technique proposed in this paper, the testing linear motion of DR6-II robot has been shown to be more accurate rather than the motion with a conventional(empirical) gain tuning technique in Doosan Mecatec Co., Ltd., by improving the dynamic response of the robot as well as synchronizing each joint velocity according to the positional command of an end-effector.

• The Journal of Korean Physical Therapy
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• v.15 no.3
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• pp.166-172
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• 2003

The aim of this study is to present the basic reference data of age and specific gait parameters for comparisons of the gait characteristics depended on amputation length of the Unilateral Trans-Tibial Prostheses. The basic gait parameters were extracted from 10 Adult, and 20 below knee(B/K) patients, 50 to 60 years of age using VICON 512 Motion Analyzer. The results were as follows; 1. The mean Cadence of the above knee(A/K) patients and below knee(B/K) patients were $87.77{\pm}8.64$ steps/min, to $99.84{\pm}11.14$ steps/min.(p<0.05) 2. The mean Walking Speed of the above knee(A/K) patients and below knee(B/K) patients were $0.84{\pm}0.15$ m/s, to $0.96{\pm}0.25$ m/s.(p>0.05) 3. The mean Stride Length of the above knee(A/K) patients and below knee(B/K) patients were $1.14{\pm}0.14\;m$, to $1.14{\pm}0.22m$.(p>0.05) 4. The mean maximal angles of joint on the hip flexion motion for different above knee(A/K) patients and below knee(B/K) patients were $34.75{\pm}10.18_{\circ}$, to $32.32{\pm}6.34_{\circ}$.(p>0.05) 5. The mean maximal angles of joint on the knee flexion motion for different above knee(A/K) patients and below knee(B/K) patients were $66.97{\pm}15.08_{\circ}$, to $52.65{\pm}9.21_{\circ}$. (p<0.05) 6. The mean maximal angles of joint on the ankle dorsi-flexion motion for different above knee(A/K) patients and below knee(B/K) patients were $14.41{\pm}4.82_{\circ}$, to $10.04{\pm}3.49_{\circ}$.(p>0.05) 7. The mean maximal angles of joint on the ankle plantar-flexion motion for different above knee(A/K) patients and below knee(B/K) patients were $5.77{\pm}3.17_{\circ}$, to $2.75{\pm}4.49_{\circ}$.(p>0.05)

• Journal of Korean Physical Therapy Science
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• v.8 no.2
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• pp.961-965
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• 2001

The aim of this study is to present the basic reference data of age and specipic gait parameters for Korean Adult. The basic gait parameters were extracted from 20 Adult, 10 men and 10 women, 21 to 24 years of age using VICON 512 Motion Analyzer. The temporal gait parameters and kinematic parameters of Korean Adult similar to other western reference data. The results were as follows: 1) The mean Cadence of the male to the female were 113.5 steps/min to 117.6 steps/min. 2) The mean Walking Speed of the male to the female were 1.30 m/s, to 1.27 m/s. 3) The mean Stride Length of the male to the female were 1.35 m, to 1.30 m. 4) The mean maximal angles of pint on the pelvic tilt motion for different male to the female were $9.80^{\circ}$ to $7.75^{\circ}$. (p<0.05) 5) The mean maximal angles of pint on the hip flexion motion for different male to the female were $22.62^{\circ}$ to $27.65^{\circ}$. (p<0.05) 6) The mean maximal angles of pint on the knee flexion motion for different male to the female were $55.78^{\circ}$ to $55.49^{\circ}$. (p>0.05) 7) The mean maximal angles of pint on the ankle dorsiflexion motion for different male to the female were $12.47^{\circ}$ to $13.39^{\circ}$. (p>0.05).

• The Journal of Korean Physical Therapy
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• v.16 no.2
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• pp.108-115
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• 2004

The aim of this study is to present the basic reference data of age and specipic gait parameters for comparisons of the gait characteristics depended on Unilateral Trans-Femoral or Trans-Tibial Prostheses. The basic gait parameters were extracted from 10 Adult, 10 above knee(A/K) patients and 10 below knee(B/K) patients, 50 to 60 years of age using VICON 512 Motion Analyzer. The results were as follows; 1) The mean Cadence of the above knee(A/K) patients and below knee(B/K) patients were $87.77{\pm}8.64$ steps/min, to $99.84{\pm}11.14$ steps/min.(p<0.05) 2) The mean Walking Speed of the above knee(A/K) patients and below knee(B/K) patients were $0.84{\pm}0.15$ m/s, to $0.96{\pm}0.25$ m/s.(p>0.05) 3) The mean Stride Length of the above knee(A/K) patients and below knee(B/K) patients were $1.14{\pm}0.14$ m, to $1.14{\pm}0.22$m.(p>0.05) 4) The mean maximal angles of joint on the hip flexion motion for different above knee(A/K) patients and below knee(B/K) patients were $34.75{\pm}10.18_{\circ}$, to $32.32{\pm}6.34_{\circ}$ .(p>0.05) 5) The mean maximal angles of joint on the knee flexion motion for different above knee(A/K) patients and below knee(B/K) patients were $66.97{\pm}15.08_{\circ}$, to $52.65{\pm}9.21_{\circ}$ .(p<0.05) 6) The mean maximal angles of joint on the ankle dorsiflexion motion for different above knee(A/K) patients and below knee(B/K) patients were $14.41{\pm}4.82_{\circ}$, to $10.04{\pm}3.49_{\circ}$ .(p>0.05) 7) The mean maximal angles of joint on the ankle plantarflexion motion for different above knee(A/K) patients and below knee(B/K) patients were $5.77{\pm}3.17_{\circ}$, to $2.75{\pm}4.49_{\circ}$ .(p>0.05)

• Transactions of the KSME C: Technology and Education
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• v.1 no.2
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• pp.193-198
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• 2013

The horseback riding simulator, an exercise training machine providing a simplified horse riding motion has been developed for aiming at healthcare. The purpose of this study was to estimate the energy expenditure without measuring bio-signals using the simulator. The test protocol was consisted of increase up to maximal intensity(Motion 9) and decrease down to minimal intensity(Motion 4) during 25 minutes, and energy expenditure was measured by portable cardiopulmonary exercise testing analyzer. There were significant differences in energy expenditure according to each riding motion. The result will be able to estimate energy expenditure using motion level, exercise time, age and gender during the riding.

• The Journal of Korean Physical Therapy
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• v.14 no.3
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• pp.129-135
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• 2002

The aim of this study is to present the basic reference data of age and specipic gait parameters for Hemiplegia Patients. The basic gait parameters were extracted from 30 Adult Hemiplegia Patients and 30 normal adult, 50 to 60 years of age using VICON 512 Motion Analyzer. The results were as follows; 1) The mean Cadence of the adult to the hemiplegia were $108.50\pm11.67$ steps/min, to $77.57\pm22.71$ steps/min. 2) The mean Walking Speed of the adult to the hemiplegia were $1.07\pm0.18m/s$, to $0.44\pm0.14m/s.$. 3) The mean Stride Length of the adult to the hemiplegia were $1.17\pm0.12m$, to $0.69\pm0.21m.$ 4) The mean maximal angles of joint on the pelvic tilt for different adult or hemiplegia Were $7.60\pm3.91.,\;to\;9.63\pm4.94.\;(P<0.05)$ 5) The mean maximal angles of joint on the hip flexion motion for different adult or hemiplegia were $29.53\pm5.03.,\;to\;25.30\pm9.94.\;(p<0.05)$ 6) The mean maximal angles of joint on the knee flexion motion for different adult or hemiplegia were $56.36\pm5.81.,\;to\; 41.64\pm17.21.(P<0.05)$ 7) The mean maximal angles of joint on the ankle dorsiflexion motion for different adult or hemiplegia were $16.65\pm2.72.,\;to\;16.53\pm7.45$(P>0.05) 8) The mean maximal angles of joint on the ankle plantarflexion motion for different adult or hemiplegia were $7.11\pm5.42.,\;to\;2.81\pm6.14.$(p<0.05)

• Journal of Korean Physical Therapy Science
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• v.9 no.1
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• pp.129-134
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• 2002

The aim of this study is to present the basic reference data of age and specipic gait parameters for Hemiplegia Patients. The basic gait parameters were extracted from 10 Adult Hemiplegia Patients, 5 left Hemiplegia Patients and 5 right Hemiplegia Patients, 50 to 60 years of age using VICON 512 Motion Analyzer. The results were as follows; 1) The mean Cadence of the left to the right hemiplegia were $75.81{\pm}28.10\;steps/min$, to $68.47{\pm}9.93\;steps/min$. 2) The mean Walking Speed of the left to the right hemiplegia were $0.45{\pm}0.28\;m/s$, to $0.44{\pm}0.14\;m/s$. 3) The mean Stride Length of the left to the right hemiplegia were $0.66{\pm}0.31\;m$, to $0.76{\pm}0.17m$. 4) The mean. maximal angles of joint on the pelvic tilt for different right or left hemiplegia were $8.59{\pm}5.13^{\circ}$, to $11.85{\pm}5.23^{\circ}$.(p>0.05) 5) The mean maximal angles of joint on the hip flexion motion for different right or left hemiplegia were $23.98{\pm}8.45^{\circ}$, to $25.81{\pm}5.39^{\circ}$.(p>0.05) 6) The mean maximal angles of joint on the knee flexion motion for different right or left hemiplegia were $29.52{\pm}10.24^{\circ}$, to $28.38{\pm}14.48^{\circ}$.(p>0.05) 7) The mean maximal angles of joint on the ankle dorsiflexion motion for different right or left hemiplegia were $14.68{\pm}5.03^{\circ}$, to $9.90{\pm}7.26^{\circ}$.(p>0.05) 8) The mean maximal angles of joint on the ankle plantarflexion motion for different right or left hemiplegia were $2.10{\pm}5.17^{\circ}$, to $8.63{\pm}5.81^{\circ}$.(p>0.05)

• International journal of advanced smart convergence
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• v.11 no.4
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• pp.57-67
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• 2022

The demand for personal training (PT), through which high exercise effects can be achieved within short-term, has recently increased. PT can achieve an exercise amount improvement effect, only if accurate postures are maintained upon performing PT, and exercise with inaccurate postures can cause injuries. However, research is insufficient on exercise amount comparisons and judging exercise accuracy on PT. This study proposes an exercise accuracy measurement algorithm and compares differences in exercise amounts according to exercise postures through experiments using a respiratory gas analyzer. The exercise accuracy measurement algorithm acquires Euler anglesfrom major body parts operated upon exercise through a motion device, based on which the joint angles are calculated. By comparing the calculated joint angles with each reference angle in each exercise step, the status of exercise accuracy is judged. The calculated results of exercise accuracy on squats, lunges, and push-ups showed 0.02% difference in comparison with actually measured results through a goniometer. As a result of the exercise amount comparison experiment according to accurate posture through a respiratory gas analyzer, the exercise amount was higher by 45.19% on average in accurate postures. Through this, it was confirmed that maintaining accurate postures contributes to exercise amount improvement.