• Science of Emotion and Sensibility
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• v.7 no.4
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• pp.19-24
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• 2004

The purpose of this study is to evaluate the possibility of identifying joint damping property through commercially available isokinetic ergometer (BIODEX). The proposed method is to estimate the damping torque of the knee joint from the difference between the external joint torque for maintaining isokinetic movement and the gravity torque of the lower leg. The damping torque was estimated at various joint angular velocities, from which the damping property would be derived. Measurement setup was composed of the BIODEX system with an external force sensor and Labview system. Matlab was used in the analysis of the damping property. The experimental result showed that the small variation in angular velocity due to acceleration and deceleration of the crank arm resulted in greater change of inertial torque than the damping torque. Therefore, the estimation of damping property from the isokinetic movement is difficult.

• ICROS
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• v.2 no.3
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• pp.25-41
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• 1996

본 고에서는 고장에 대한 내성을 갖는 로봇 시스템에 관련된 전반적인 연구분야에 대한 소개를 하였으며 구조적인 측면에 중점을 두어 기술되었으나, 고장에 내성을 갖는 위치/속도 센서, 힘/토크 센서 그리고 로봇 제어에 관련된 하드웨어와 소프트웨어 등과 같은 로봇 구성 요소들의 개발에 관한 연구, 고장이 발생하였을 경우에 수행중인 작업을 지속적으로 그리고 성공적으로 수행할 수 있도록 하는 고장회복을 위한 제어기법 등에 관한 구체적인 방법 등에 대하여 매우 활발한 연구가 필요된다. 마지막으로, 이러한 고장에 대한 내성을 갖는 로봇 매니퓰레이터의 개발에 관한 중요성이 인식되어 국내에서도 높은 관심과 더불어 활발한 연구가 진행되었으면 한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1315-1316
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• 2013

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.299-300
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.367-368
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• 2011

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.1117-1118
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• 2011

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.1593-1594
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• 2011

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.1
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• pp.57-65
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• 2001

The speed control without a speed sensor is expected strongly to progress reliability, simplicity and cost performance of Induction Motor(I.M) systems. Also, it contributes to expansion of I.M systems into various industrial application fields. This paper investigates a novel speed sensorless control method of I.M considering the secondary resistance identification based on the transientless torque control technique. Especially, this paper aimed at the identification of the secondary resistance simultaneously with speed estimation superposing of sinusoidal flux wave to a constant flux value. Furthermore, the secondary flux with some frequency is controlled independently on torque control. The proposed speed estimation method is derived from a motor circuit equation theoretically and also it can be conducted easily by detecting primary motor currents and primary voltage commands at every sampling time. Some numerical simulations with the assumption of using a pulse width modulation(PWM) voltage source inverter are performed to verify the proposed method.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.4
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• pp.309-316
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• 2016

In this study, we described the design of a three-axis force/torque sensor for measuring the force and torque in a lower-limb rehabilitation robot. The three-axis force/torque sensor is composed of Fx force sensor, Fz force sensor and Tz torque sensor. The sensing element for Fx force sensor and Tz torque sensor is used in a two-step parallel plate beam, and that of Fz force sensor is used in a parallel plate beam. The rated loads of Fx force sensor, Tz torque sensor and Fz force sensor are 300 N, 15 N m and 100 N, respectively. The three-axis force/torque sensor was designed using the finite element method, and manufactured using strain-gauges. The three-axis force sensor was further characterized. As a result, the interference error of the three-axis force/torque sensor was < 1.24%, the repeatability error of each sensor was < 0.03%, and the non-linearity was < 0.02%.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.2
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• pp.170-177
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• 2012

A force/torque sensor using carbon fiber plate was designed and developed to make the sensor be able to measure a wide range of multi degree of force and torque. Using carbon fiber plate of 0.3 mm thickness, the sensor was designed and developed, which has a ${\mu}N$ level order of resolution and about 0.01 N ~ 390 N of wide measurement range. The elastic deformation part has a tripod plate structure and strain gauges are attached on the part to detect the force/torque. The coefficient of determination for the sensor is over 0.955 by the calibration experiment so that the linearity of the sensor is confirmed to be good. Also, experiments on applying 0.005 ~ 40 kg (0.05 ~ 390 N) to each axis were implemented and the sensor is proved to be safe under a high load. Finally, to verify the function calculating the direction of load vector, the directions of various load vectors which have the same magnitude but different directions and the directions of the calculated load vectors are compared and analyzed to accord well.