• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.768-771
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• 1997

Geometric probing addresses the problem of determining geometric aspects of a structure from the mathematics and results of a physical measuring device such as a probe. This paper presents a new algorithm to recognize the shape of an unknown object by using a robot hand with a force and torque sensor. The new algorithm is called S.E.P.(Shape Exploration Procedure) which finds the global shape of an unknown object. The proposed method is composed of three major parts, finding contact informations such as contact point, calculation of shape information such as curvature, and expression of global shape from these informations. Comparing with the conventional approaches, the advantages of the proposed method are explained and verified by conducting experiments with a 3-dof SCARA robot.

• Tribology and Lubricants
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• 제26권4호
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• pp.224-229
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• 2010

A new test rig is presented to measure friction losses at journal bearings in a reciprocating compressor. This rig consists of a test bearing, torque sensor, driving motor and loading parts especially for vertical shaft. Friction losses are obtained by measuring torque between motor and test bearing. The experiments are carried out at several rotational speeds and temperatures. The test results are presented and discussed.

• Journal of Advanced Marine Engineering and Technology
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• 제28권2호
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• pp.269-276
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• 2004

A marine diesel engine should realize optimal efficiency operation while reducing NOx. Fuel injection systems by electronic control can become effective means for that. Although it would be able to get more precise engine control compared to the mechanical injection system, it needs some accurate and instant information in order to bring its ability into full play while sailing on the sea. Very important information of them is shaft torque and continuous combustion pressure of all cylinders. The system presented in this report can deliver those data.

• Journal of Advanced Marine Engineering and Technology
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• 제24권6호
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• pp.34-42
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• 2000

In this paper conventional technique will be described, which can be used for the measuring various parameters of induction motor. This is followed by presenting some other, alternative, techniques. The two tests are described which are suitable to obtain the electrical parameters of symmetrical 1hp three-phase squirrel-cage induction motor. These are the blocked rotor test and no load test. By the application of these, it is possible to determine the parameters which are presented in the steady-state equivalent-circuit of determining an induction motor. One conventional method of determining the inertia of an induction motors is obtained by performing retardation tests. The angular rotor speed of the motor is monitored, following its disconnection from the stator supply. Since the inertia torque J dw/dt contains the inertia coefficient J and the friction and windage torque Bw contains the coefficient B, then J and B can be determined by performing retardation tests.

• Journal of Advanced Marine Engineering and Technology
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• 제23권1호
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• pp.19-24
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• 1999

In this paper the emission characteristic of the ship's diesel engine with CPP(Controllable Pitch Propeller) were investigated under the passage test on the sea. As the results it is confirmed that the NOx.$CO_x$ concentrations increase as the engine speed increases and the torque decreases. but the amount of NOx, COx emissions(g./k Wh) decrease as the torque increase regardless of the engine speed. Also it is compared with the NOx concentra-tions measured by the two method-ECC(Electrochemical Cell)and CLD(Chemiluminescence Detector)for the correct measurement and the ECC indicated higher value than the CLD.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.293-296
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• 2002

This paper presents an implementation of Direct torque control(DTC) of Reluctance Synchronous Motor(RSM) drives for an industrial servo drive system with stator current space vector. The estimation of the stator flux magnitude are obtained by using the neural network from measuring the modulus and angle of the stator current space vector. The develolled digitally high-performance control system are shown a good response characteristic of control results and high performance features using 1.0kW RSM.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 전력전자학술대회 논문집
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• pp.234-238
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• 1998

Parameter estimation of induction motor for vector control presented in this paper can be easily implemented and applied to inverters in the industrial field, because it needs no additional hardware such as voltage sensor and measuring equipment. At first, the stator resistance including switching loss of inverter is measured by simple voltage-current equation. Next, in pre-magnetization of machine by imposing the d-axis constant field-current, q-axis torque current is forced to the machine until its speed feedback reachs to pre-defined level of speed limit. At this time, we can measure the rotor time-constant by decreasing the distorted output-voltage of inverter. At last, stator inductance, transient inductance, and moment of inertia can be measured by the relationship of output voltage, output torque and speed feedback. The validity and usufulness of this method is verified by experimental results.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.431-432
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• 2006

In this study, the effect of the temperature of magnesium slurry was investigated by mechanical stirring method. The evaluations of rheological behavior of AM50A magnesium alloy were measuring of viscosity and microstructures in the semisolid state. The apparent viscosity was investigated at continuous cooling rate using a concentric cylinder viscometer. Measurement of viscosity measures torque that act to stirrer rotating in slurry doing continuous cooling using torque-meter and expressed by POWER-LAW. Microstructures were observed after mechanical stirring that enforce time at steady state temperature of solid fraction.

• 한국진공학회지
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• 제11권2호
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• pp.81-86
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• 2002

KSTAR 진공용기의 대형포트에 사용하려고 계획하고 있는 Helicoflex 개스킷의 특정 모델에 대해 플랜지 체결 특성 특히 토크(또는 선하중) 및 변형량과 기체누설률의 관계를 조사하여 기밀곡선을 구하는 실험을 수행했다. 그 결과 상온에서는 Ml8 볼트의 경우 토크 2500 kg.cm에서 Helicoflex를 채용한 플랜지의 기체누설률은 $2\times10^{-1}$ /mbar.L/s이하였다.

• 수산해양기술연구
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• 제55권4호
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• pp.402-410
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• 2019

This paper deals with the disturbance observer (DOB) based sliding mode control (SMC) for a DC motor to control motor rotating speed precisely and to ensure strong robustness against disturbance including load torque and parameter variation. The reason of steady state error in speed on conventional SMC without DOB is analyzed in detail. Especially, the suggested DOB is designed to prevent measuring noise and harmonics caused by derivative operation on rotating speed. The control performance of the DOB based SMC is evaluated by the various simulations. The simulation results showed that the DOB based SMC had more robust performance than the SMC system without DOB. Especially, precise speed control was possible even though motor parameter variation and load torque was added to the system.