• Korean Journal of Remote Sensing
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• v.31 no.2
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• pp.85-99
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• 2015

TDI CCD sensors are being used for most of the electro-optical camera mounted on the low earth orbit satellite to meet high performance requirements such as SNR and MTF. However, the CMOS sensors which have a lot of implementation advantages over the CCD, are being upgraded to have the TDI function. A few methods for improving the issue of motion blur which is apparent in the CMOS sensor than the CCD sensor, are being introduced. Each pixel can be divided into a few sub-pixels to be read more than once as is the same case with three or four phased CCDs. The fill factor can be reduced intentionally or even a kind of mask can also be implemented at the edge of pixels to reduce the blur. The motion blur can also be reduced in the TDI CMOS sensor by reducing the integration time from the full line scan time. Because the integration time can be controlled easily by the versatile control electronics, one of two performance parameters, MTF and SNR, can be concentrated dynamically depending on the aim of target imaging. MATLAB simulation has been performed and the results are presented in this paper. The goal of the simulation is to compare dynamic MTFs affected by the different methods for reducing the motion blur in the TDI CMOS sensor.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.1
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• pp.65-71
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• 2013

In this work, new smart phone based moving target detection is proposed. In order to implement the task, methods of real time image transmission from network camera, motion detecting algorithm and its effective implementation are also addressed. The network camera transfers image data by MJPEG format which contains various information such as data and IP address, and the smart phone separates the image data received through a WiFi module. Later, the image data is converted to a Bitmap image format, and with the help of the embedded OpenCV library on a smart phone and algorithm, it was found that the moving object was identified effectively in terms of real time monitoring and detection.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.1
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• pp.56-64
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• 2013

We propose an efficient minimum-time cornering motion planning algorithms for differential-driven wheeled mobile robots with motor control input constraint, under piecewise constant control input sections. First, we established mobile robot's kinematics and dynamics including motors, divided the cornering trajectory for collision-free into one translational section, followed by one rotational section with angular acceleration, and finally the other rotational section with angular deceleration. We constructed an efficient motion planning algorithm satisfying the bang-bang principle. Various simulations and experiments reveal the performance of the proposed algorithm.

• Journal of Ocean Engineering and Technology
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• v.22 no.5
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• pp.138-141
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• 2008

This paper treats the development of a new type of deep draught semisubmersible offshore structural shape that has excellent heave motion response and less down-time. This new type of semisubmersible shape is characterized by heave dampers at each pontoon corner and appropriate column size adjustment to achieve the desired cancellation and resonance motion period. It was found that the final model had efficient workability, based on the wavescatter diagrams for the GoM and North Atlantic ocean, due to less heave motion, although the specific heave response at the 100 year return period wave condition in the North Atlantic was more or less increased.

• Journal of the Korean Society of Safety
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• v.17 no.2
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• pp.58-62
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• 2002

Longitudinal wave tests with finite elastic medium were performed to investigate the difference between measured values and theoretical values of propagation velocity and elasticity modulus. Each accelerometer was attached on finite elastic medium with same phase and different positions to check the particle motion. The results show that measured values of elasticity moduli from both time domain and frequency domain were similiar to theoretical value. Polarity of signal depends entirely on the phase of accelerometer. It proved that the propagation velocity and the particle motion are in the same direction when a compressive stress is applied. And also the propagation velocity and the particle motion depend on the intensity of the stress and material properties respectively.

• Journal of Institute of Convergence Technology
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• v.6 no.2
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• pp.9-13
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• 2016

Robot usually requires spline motion to move through multiple knots. In this paper, catmull-rom spline method is applied to the trajectory planning of industrial robot in task space. Centripetal catmull-rom is selected to avoid self-intersection and slow motion which can be occurred in uniform and chordal spline. The method to set two control points are proposed to satisfy velocity conditions of initial and final knots. To optimize robot motion, time scaling method is presented to minimize margin between real robot value and maximum value in velocity and acceleration. The simulation results show that the proposed methods are applied to trajectory planning and robot can follow the planned trajectory while robot motion does not exceed maximum value of velocity and acceleration.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.161.5-161
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• 2001

Robots are required to assist our activities in daily life. In this paper, we focus on arm movement to catch moving object as one of important tasks frequently performed by human. We propose an algorithm which enables a robot to perform human-like arm motion to catch a moving object. First we analyze human hand trajectories and velocity profiles to catch an object. From the experimental results, we extract some characteristics in the process of approaching and following a moving object and confirm that these are necessary to realize human-like motion. We then adopt an instantaneous optimal control method which evaluates the error and energy cost at each sampling step, and design two time-varying weight matrices to introduce human characteristic into robot motion. The matrix concerning the error is defined as a time-increasing ...

• Journal of Korean Society of Industrial and Systems Engineering
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• v.13 no.22
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• pp.71-78
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• 1990

Some problems to assess the safety of automated man-machine system are studied in many ways. The difficulty occurred in this system is the vagueness of human behavior. Fuzzy set theory is used to assess the human behavior in safety analysis. The unsafe behavior listed top 10 in accident statistics would be explained as the factors of human vagueness. Three cases are considered, which consist of man-machine system as man-man, man-machine, machine-machine types. For the design of safe task, using characteristics of work performance, each motion cycle time is required to know the rate of learning. Approach of human behavior to the standard motion means more safe motion. It is important to design the works as to minimize the time performance to the standard motion's, which utilize the control of risk potential with easy. In that process, use of fuzzy set theory is appropriate to analyze the human behavior to identify its vagueness.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.4
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• pp.315-324
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• 2011

This paper presents a historical study on the derivation of the differential equation of motion for the single-degree-of-freedom m-k system with the harmonic excitation. It was Euler for the first time in the history of vibration theory who tackled the equation of motion for that system analytically, then gave the solution of the free vibration and described the resonance phenomena of the forced vibration in his famous paper E126 of 1739. As a result of the chronological progress in mechanics like pendulum condition from Galileo to Euler, the author asserts two conjectures that Euler could apply to obtain the equation of motion at that time.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.8
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• pp.769-776
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• 2007

This paper proposes the human arm motion tracking algorithm based on the signal processing for surface EMG (electromyogram) sensors attached on both upper arm and shoulder. The signals acquired by using surface EMG sensors are processed with choosing the maximum in a short period, taking the absolute value, and filtering noises out with a low-pass filter. The processed signals are directly used for the motion generation of virtual arm in real time simulator. The virtual arm of simulator has two degrees of freedom and complies with the flexion and extension motions of elbow and shoulder. Also, we show the validity of the suggested algorithms through the experiments.