• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.360-361
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• 2006

This paper describes a wire and wireless network sensor for temperature and humidity measurements. The network sensor comprises PLC(Power Line Communication) and RF transmitter(433MHz) for acquiring an internal (on-board) sensor signal, and measured data is transmitted to a main processing unit. The network sensor module is consist of MEMS sensor, 10-bit A/D converter, pre-amp., gain-amp., ADUC812 one chip processor and PLC/RF transmitting unit. The temperature and humidity sensor is based on MEMS piezoelectric membrane structure and is implemented by using dual function sensor for smart home and smart building.

• Journal of Magnetics
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• 제18권2호
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• pp.159-162
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• 2013

We present how to optimize the operation condition including frequency of the orthogonal fluxgate sensor in this paper. The orthogonal fluxgate sensor was fabricated with a Co-based amorphous wire with 10 mm long and 100 ${\mu}m$ in the diameter and a 270-turn pickup coil wound on the amorphous wire. In order to investigate the frequency dependence of the sensitivity, output spectra of the sensor which was connected by using a coaxial cable with various lengths of 0.5-5 m were measured with a RF lock-in amplifier. The maximum sensitivities were obtained at different frequencies according to coaxial cable lengths. It was found that the optimal operation frequencies, at which maximum sensitivities were appeared, were almost identical to the frequencies of impedance resonance. The maximum sensitivity and optimal operation frequency were 1.1 V/Oe (${\approx}$ 11000 V/T) and 1.25 MHz respectively.

• 센서학회지
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• 제15권1호
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• pp.1-6
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• 2006

We fabricated Si nano-wire MOSFET by using the conventional photolithography with a $1.5{\mu}m$ resolution. Si nano-wire was fabricated by using reactive ion etching (RIE), anisotropic wet etching and thermal oxidation on a silicon-on-insulator (SOI) substrate, and its width is 30 nm. Logarithmic circuit consisting of a NMOSFET and Si nano-wire MOSFET has been constructed for application to high-sensitivity image sensor. Its sensitivity was 1.12 mV/lux. The output voltage swing was 1.386 V.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.609-612
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• 2001

To investigate the magnetic field distribution of power line, we used amorphous wire sensor. And we discuss extremely low frequency magnetic field distribution dependent upon arrangement of power line and shielding pipe made from iron or alumimum materials by both measurement and FEM(Finite Element Method) analysis. Appling current of single phase 60 [Hz] 15 [A] is supplied to copper wire coated enamel resign. As the results, we confirmed that linear characteristics of amorphous wire sensor is very excellent and measurement value agrees with FEM calculation. Magnetic field distribution due to shielding materials is changed by permeability and conductivity.

• 대한기계학회논문집
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• 제19권1호
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• pp.263-270
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• 1995

The use of the shape memory alloy, Nitinol wire, is investigated as an actuator for enhancing the damping in structural vibration systems. The first-order mathematical model of the Nitinol wire is obtained from the experimental data for an actuator. Finite element method is utilized for the strain gage sensor model, which is installed at the root of cantilever beam. A simple system, cantilever beam, is built as a flexible structural system to implement a control law with the Nitinol wire actuator. The system model including sensor and actuator is derived, which agrees with the experimental results. The actuator dynamics is augmented with the system so as to design PI controller and the one of robust controllers, LQG/LTR controller, and the control laws are implemented experimentally. The experimental study shows the feasibility of utilizing the Nitinol wire as an actuator for the purpose of vibration control.

• Interaction and multiscale mechanics
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• 제3권3호
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• pp.257-266
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• 2010

A novel resonance based proximity DC current sensor is proposed. The sensor consists of a piezo sensed and actuated cantilever beam with a permanent magnet mounted at its free end. When the sensor is placed in proximity to a wire carrying DC current, resonant frequency of the beam changes with change in current. This change in resonant frequency is used to determine the current through the wire. The structure is simulated in micro and meso scale using COMSOL Multi physics software and the sensor is found to be linear with good sensitivity.

• Coupled systems mechanics
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• 제5권2호
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• pp.191-201
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• 2016

Coupled structures are widely seen in civil and mechanical engineering. In coupled structures, monitoring the translational motion of its key components is of great importance. For instance, some coupled arms are equipped with a hydraulic piston to provide the stiffness along the piston axial direction. The piston moves back and forth and a distance sensing system is necessary to make sure that the piston is within its stroke limit. The measured motion data also give us insight into how the coupled structure works and provides information for the design optimization. This paper develops two distance sensing systems for coupled structures. The first system measures distance with ultrasonic sensor. It consists of an ultrasonic sensing module, an Arduino interface board and a control computer. The system is then further upgraded to a three-sensor version, which can measure three different sets of distance data at the same time. The three modules are synchronized by the Arduino interface board as well as the self-developed software. Each ultrasonic sensor transmits high frequency ultrasonic waves from its transmitting unit and evaluates the echo received back by the receiving unit. From the measured time interval between sending the signal and receiving the echo, the distance to an object is determined. The second distance sensing system consists of a wire draw encoder, a data collection board and the control computer. Wire draw encoder is an electromechanical device to monitor linear motion by converting a central shaft rotation into electronic pulses of the encoder. Encoder can measure displacement, velocity and acceleration simultaneously and send the measured data to the control computer via the data acquisition board. From experimental results, it is concluded that both the ultrasonic and the wire draw encoder systems can obtain the linear motion of structures in real-time.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.116.1-116
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• 2001

In the near future, drive-by-wire systems will replace mechanical systems of vehicles. Since there would be no mechanical redundancy in the x-by-wire subsystem, it needs to improve the reliability of the system using fault diagnosis of sensors and actuators. This paper proposes a Kalman filter based fault diagnosis method for the vehicle with the drive-by-wire system, which includes steer-by-wire, brake-by-wire and throttle-by-wire systems. We will show that the proposed method is successful in fault detection and isolation for single sensor/actuator faults of the vehicle system.

• Journal of Advanced Marine Engineering and Technology
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• 제28권3호
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• pp.531-537
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• 2004

In this paper, the static and dynamic characteristics in the sensor tube of a mass flow controller(MFC) were studied by experiments. In the sensor tube of MFC. the difference of temperature between inlet and outlet was necessary for calculating the mass flow rate. Therefore, the relations among flow rate, heat generated by heating wire. and sensor location were investigated to find optimized condition. Finally, the relation between sensor voltage through analog digital conversion(ADC) and flow rate in the sensor tube can be represented. Based on this study, static and dynamic characteristics of sensor tube can be used for design of mass flow controller.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.295-296
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• 2006

We developed wire frame drive unit based on SMA for the 3D Shape display. Our basic concept is wire frame combination connected with a chain form which can create various shapes and it compared with pin array mechanism which is not able to display mushroom shape. It imitates antagonist mechanism of human musculoskeletal system. we create similar motion using repair-relaxation mechanism and locking mechanism by SMA. Therefore, in this paper, we propose SMA control solution for actuating repair-relaxation mechanism and locking mechanism. In our control system. we use optical sensor and quantitative angle between wire frames for closed loop control. And we supply amplified current for SMA by circuit composed of transistor and apply PWM signal to circuit for efficient control. So, wire frame drive unit enable diversity angle control based on sensor data. And then combination of wire frame drive units will create various objects.