• Proceedings of the KIPE Conference
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• 2003.11a
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• pp.132-136
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• 2003

Generally, PM BLDC drive system is necessary that the three Hall-ICs evenly be distributed around the stator circumference and encoder be installed in case of the 3 phase motor. So, the Hall-ICs are set up in this motor to detect the main flux from the rotor, and the output signal from Hall-ICs is used to drive a power transistor to control the winding current. However, instead of using three Hall-ICs and encoder, we used only two Hall-ICs for the permanent magnet rotor position and for the speed feedback signals, and also for a micro controller of 16-bit type (80C196KC) with the 3 phase PM BLDC whose six stator and two rotor designed. Two Hall-IC Hc and $H_B$ are placed on the endplate at 120 degree intervals, and with these elements, we estimated information of the others phase in sequence through a rotating rotor.

• Journal of ILASS-Korea
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• v.21 no.1
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• pp.1-6
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• 2016

A gasoline injector rig which can measure cumulative injected fuel mass under a vehicle driving condition was developed. The measurement system consists of an engine control unit (ECU), data acquisition (DAQ) and injected fuel collection system using loadcells. By supplying reconstructed sensor signals which simulate the real vehicle's sensor signals to the ECU, the ECU drives injectors as if they were driven in the vehicle. The vehicle's performance was computer simulated by using $GT-Suite^{(R)}$ software based on both engine part load performance and automatic transmission shift map. Throttle valve position, engine and vehicle speed, air mass flow rate et al. were computer simulated. The used vehicle driving pattern for the simulation was FTP-75 mode. For reconstructing the real vehicle sensor signals which are correspondent to the $GT-Suite^{(R)}$ simulated vehicle's performance, the DAQ systems were used. The injected fuel was collected with mess cylinders. The collected fuel mass in the mess cylinder with elapsed time after starting FTP-75 driving mode was measured using loadcells. The developed method shows highly improved performance in fast timing and accuracy of the cumulative injected fuel mass measurement under the vehicle driven condition.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.1 no.2
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• pp.81-92
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• 2006

Objectives: To review recent findings from physiologic research about the nature of proprioceptive spinal reflex, proposed explanation for mechanisms of musculoskeletal problems associated with propriceptive dysfunction and techniques controlling this problem. Methods: MEDLINE databases were searched using various combinatins of the keywords proprioception, spinal reflex, somata-somatic reflex, spinal manipulation, muscle spindle, Golgi-tendon organ, along with searching the related articles and textbooks. Results and Conclusion: Proprioceptors(muscle spindle, Golgi-tendon organs) monitor the position of joints, tension in tendons and ligaments, and the state of muscular contraction. Disturbed activity of proprioceptive spinal reflex can cause chronic state of increased muscle stiffness, pain, deficiencies both in muscle coordination and propioception, and so on. All kinds of techniques that control proprioceptive primary afferent neurons can affect the motor control system and evoke changes in the neuromuscular system.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.81-81
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• 2000

We use camera to apply human vision system in measurement. To do that, we need to know about camera parameters. The camera parameters are consisted of internal parameters and external parameters. we can fix scale factor&focal length in internal parameters, we can acquire external parameters. And we want to use these parameters in automatically driven vehicle by using camera. When we observe an camera parameters in respect with that the external parameters are important parameters. We can acquire external parameter as fixing focal length&scale factor. To get lane coordinate in image, we propose a lane detection filter. After searching lanes, we can seek vanishing point. And then y-axis seek y-sxis rotation component(${\beta}$). By using these parameter, we can find x-axis translation component(Xo). Before we make stepping motor rotate to be y-axis rotation component(${\beta}$), '0', we estimate image coordinates of lane at (t+1). Using this point, we apply this system to Kalman filter. And then we calculate to new parameters whick make minimum error.

• Journal of Mechanical Science and Technology
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• v.15 no.9
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• pp.1302-1310
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• 2001

This paper introduces modeling and simulation results for pipeline inspection gauge (PIG) with bypass flow control in natural gas pipeline. The dynamic behaviour of the PIG depends on the different pressure across its body and the bypass flow through it. The system dynamics includes: dynamics of driving gas flow behind the PIG, dynamics of expelled gas in front of the PIG, dynamics of bypass flow, and dynamics of the PIG. The bypass flow across the PIG is treated as incompressible flow with the assumption of its Mach number smaller than 0.45. The governing nonlinear hyperbolic partial differential equations for unsteady gas flows are solved by method of characteristics (MOC) with the regular rectangular grid under appropriate initial and boundary conditions. The Runge-Kuta method is used for solving the steady flow equations to get initial flow values and the dynamic equation of the PIG. The sampling time and distance are chosen under Courant-Friedrich-Lewy (CFL) restriction. The simulation is performed with a pipeline segment in the Korea Gas Corporation (KOGAS) low pressure system, Ueijungboo-Sangye line. Simulation results show us that the derived mathematical model and the proposed computational scheme are effective for estimating the position and velocity of the PIG with bypass flow under given operational conditions of pipeline.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.612-618
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• 2009

Recently the roles of railways about the prevention of global warming caused by greenhouse gases and for low carbon green growth are larger than ever. And the railroad-related research institutions have been active in researching for energy conservation. Especially the urban railroad has been emerged as the best means of transportation compared to the general public transportation systems in punctuality, stability, ecology and etc. In operating the urban railroad system there are various ways for energy savings. In the larger category, One is the hardware aspect according to the structure of the vehicle and the development of control systems. The other is the software aspect which efficient train operation can be made through control of driving patterns and driving diagram. In this paper, there is sense to analyze the result in verifying expectation relation with variable and the use of electric power on this after selecting main variables that can influence to the energy of the train operation in the software aspect. First, after collecting the basic data related to operation(train speed, operating hours, power consumption, the position of stopping station, electrical power system etc.) and according to this, investigating the consumption of the energy of the operation, in the side of energy consumption deducing and analyzing problem, this will be found solutions.

• 연구논문집
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• s.28
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• pp.73-87
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• 1998

A pneumatic control system of compressed air as a working fluid has a variety of advantages such as low price, high respondence, non-explosion and good control performance and thus has many applications in the field of automobile, electronic and semiconductor industry. However, it has a difficulty in contolling a precise position due to quick response of system and compressibility of working fluid and. in particular, shock stress may occur due to an external load, resulting in fracture of a cylinder cap unless cushion device is equipped in the linear actuator. To avoid this, a cushion device should be installed for damping effect of the external load and the supply pressure as well as for decreasing shock stress and vibration caused by high speed rotation. Previous studies include dimensionless analyses and computer simulations of cushion capability and experiments of horizontally-mounted cylinder performances. A new attempt is experimentally made in this study using a vertically-mounted cylinder under an operation condition of 4, 5 and 6 (bar) as supply pressure and 40, 70 and 100 (kgf) as external load. It turns out that the cushion pressure is mainly a function of the external load rather than the supply pressure. The cushion characteristics was also revealed in the meter-in circuit.

• ETRI Journal
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• v.37 no.6
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• pp.1165-1175
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• 2015

This paper presents an advanced sensorless permanent magnet (PM) brushless motor controller integrated circuit (IC) employing an automatic lead-angle compensator. The proposed IC is composed of not only a sensorless sine-wave motor controller but also an isolated gate-driver and current self-sensing circuit. The fabricated IC operates in sensorless mode using a position estimator based on a sliding mode observer and an open-loop start-up. For high efficiency PM brushless motor driving, an automatic lead-angle control algorithm is employed, which improves the efficiency of a PM brushless motor system by tracking the minimum copper loss under various load and speed conditions. The fabricated IC is evaluated experimentally using a commercial 200 W PM brushless motor and power switches. The proposed IC is successfully operated without any additional sensors, and the proposed algorithm maintains the minimum current and maximum system efficiency under $0N{\cdot}m$ to $0.8N{\cdot}m$ load conditions. The proposed IC is a feasible sensorless speed controller for various applications with a wide range of load and speed conditions.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.12
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• pp.1067-1071
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• 2013

A 3D visual sensing method using a laser structured beam is presented for robotic tracking applications in a simple and reliable manner. A cylindrical shaped laser structured beam is proposed to measure the pose and position of the target surface. When the proposed laser beam intersects on the surface along the target trajectory, an elliptic pattern is generated. Its ellipse parameters can be induced mathematically by the geometrical relationship of the sensor coordinate and target coordinate. The depth and orientation of the target surface are directly determined by the ellipse parameters. In particular, two discontinuous points on the ellipse pattern, induced by seam trajectory, indicate mathematically the 3D direction for robotic tracking. To investigate the performance of this method, experiments with a 6 axis robot system are conducted on two different types of seam trajectories. The results show that this method is very suitable for robot seam tracking applications due to its excellence in accuracy and efficiency.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.12
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• pp.3909-3916
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• 1996

Magnetic bearing is the machine element that supports the shaft without mechanical contact using the magnetic force induced by permanent magnet of electromagnet. Active magnetic bearing system is composed of sensor, controller, power amplifier, and electromagnet. If all the elements were dieal, shaft position could be controlled to sensor resolution, Because each elements inreal system have mechanical and electricla losses and nonlinearity, it is impossible to attain the desired performance using general control algorithm. So far it has been studied on improvement of the control algorithm of the electric characteristics of each elements. Another factors to affect shaft behavior are the manufacturing errors due to machine work, and assembling errors due to accumulate manufacturing errors of the radial magnetic bearing. This paper describes that the shaft behavior due to accumulate manufacturing errors and asymmetric bolting. This paper describes that the shaft behavior due to assembling errors of the radial bearings donot affect the rotaitonal accuracy of the shaft. But when the amplitude of the assembling errors increasees over the certain value, the bearing can not support the shaft properly.