• Journal of Institute of Control, Robotics and Systems
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• v.12 no.9
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• pp.861-867
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• 2006

This paper presents the robust mobile robot localization method exploiting redundant motion information acquired from three optical mice that are installed at the bottom of a mobile robot in a regular triangular form. First, we briefly introduce a low-cost optical motion sensor, HDNS-2000, and a commercial device driver development tools, WinDriver, to be used in this research. Second, we explain the basic principle of the mobile robot localization using the motion information from three optical mice, and propose the least squares based localization algorithm which is robust to the noisy measurement and partial malfunctioning of optical mice. Third, we describe the development of the experimental optical odometer using three PC optical mice and the user-friendly graphic monitoring program. Fourth, simulations and experiments are performed to demonstrate the validity of the proposed localization method and the operation of the developed optical odometer. Finally, along with the conclusion, we suggest some future work including the installation parameter calibration, the optical mouse remodelling, and the high-performance motion sensor adoption.

• International Journal of Control, Automation, and Systems
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• v.6 no.5
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• pp.713-721
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• 2008

This paper presents the robust velocity estimation of an omnidirectional mobile robot using a polygonal array of optical mice that are installed at the bottom of the mobile robot. First, the velocity kinematics from a mobile robot to an array of optical mice is derived as an overdetermined linear system. The least squares velocity estimate of a mobile robot is then obtained, which becomes the same as the simple average for a regular polygonal arrangement of optical mice. Next, several practical issues that need be addressed for the use of the least squares mobile robot velocity estimation using optical mice are investigated, which include measurement noises, partial malfunctions, and imperfect installation. Finally, experimental results with different number of optical mice and under different floor surface conditions are given to demonstrate the validity and performance of the proposed least squares mobile robot velocity estimation method.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.6
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• pp.555-562
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• 2013

This paper presents the optimal array of optical mice for the accurate velocity estimation of a mobile robot. It is assumed that there can be some restriction on the installation of two or more optical mice at the bottom of a mobile robot. First, the velocity kinematics of a mobile robot with an array of optical mice is derived, which maps the velocity of a mobile robot to the velocities of optical mice. Second, taking into account the consistency in physical units, the uncertainty ellipsoid is obtained to represent the error characteristics of the mobile robot velocity estimation owing to noisy optical mouse measurements. Third, a simple but effective performance index is defined as the inverse of the volume of the uncertainty ellipsoid, which can be used for the optimization of the optimal optical mouse placement. Fourth, simulation results for the optimal placement of three optical mice within a given elliptical region are given.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.7
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• pp.543-551
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• 2016

This paper presents the analysis and implementation of traveling surface characteristics test equipment using optical mice in connection with the velocity estimation of a mobile robot equipped with optical mice. In the traveling surface characteristics test equipment, a traveling surface sample is made to rotate toward stationary optical mice instead of a mobile robot equipped with optical mice moving over a traveling surface. First, the conceptual design and operational principle of the traveling surface characteristics test equipment is explained. Second, the velocity kinematics of the traveling surface characteristics test equipment is formulated; based on this, the parameter setting of the traveling surface characteristics test equipment is described. Third, the implementation of the traveling surface characteristics test equipment is described in detail, including the mechanical design and construction and the hardware and software development. Fourth, using the prototype of the traveling surface characteristics test equipment, the experimental results of the statistical parameter extraction for different traveling surface samples are given. Finally, some potential usages of the traveling surface characteristics test equipment are discussed.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.10
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• pp.978-982
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• 2007

This paper presents the velocity estimation of a mobile robot using a regular polygonal array of optical mice that are installed at the bottom of a mobile robot. First, the basic principle of the proposed velocity estimation method is explained. Second, the velocity kinematics from a mobile robot to an array of optical mice is derived as an overdetermined linear system. Third, for a given set of optical mouse readings, the mobile robot velocity is estimated based on the least squares solution to the obtained system. Finally, simulation results are given to demonstrate the validity of the proposed velocity estimation method.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.145-146
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• 2007

This paper presents the sensitivity analysis of the leasst qsuares velocity estimation of an omnidirectional mobile robot using a regular polygonal array of optical mice. First, the velocity kinematics from a mobile robot to an array of optical mice is derived as an overdetermined linear system. Then, for a given set of optical mouse readings, the least squares velocity estimation of a mobile robot is obtained as the simple average. Finally, the sensitivity analysis of the proposed least squares velocity estimation to imprecise installation is made.

• Journal of the Optical Society of Korea
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• v.11 no.1
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• pp.26-33
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• 2007

We demonstrate the capability of differential-phase optical coherence tomography (DP-OCT) to detect superparamagnetic iron oxide (SPIO) nanoparticles taken up by liver parenchymeal macrophages (Kupffer cells). We apply an external time-varying high-intensity focused magnetic field. Our experiments demonstrate a novel diagnostic modality to detect macrophages that have taken up SPIO nanoparticles. Magnetic force acting on the nanoparticles was varied by applying a sinusoidal current to a solenoid containing a conical iron core that substantially increased and focused the magnetic field strength ($B_{max}$ = 2 Tesla). $ApoE^{-/-}$ mice were sacrificed 2 days post intravenous injections of different SPIO doses (1.0, and 0.1 mmol Fe/kg body weight). Livers of $ApoE^{-/-}$ mice with and without injection of SPIO nanoparticles were investigated using DP-OCT, which detects tissue movement with nanometer resolution. Frequency response of iron-laden liver movement was twice the stimulus frequency. Movement was not observed in livers of control mice. Results of our experiments indicate DP-OCT is a candidate methodology to detect tissue based macrophages containing SPIO nanoparticles excited by an external focused magnetic field.

• The Journal of Internal Korean Medicine
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• v.31 no.3
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• pp.513-525
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• 2010

Objectives : This study was carried out to investigate the effects of Goihwa-san(GHS) against ulcerative colitis induced by DSS (dextran sulfate sodium). Method : The sample group was divided into three. The control group consisted of mice that were not inflammation-induced. The pathological group was composed of untreated colitis elicited mice. The experimental group was administered GHS after colitis elicitation. The effects on ulcerative colitis were evaluated by the morphological change of colonic mucosa, the anti-oxidant effect, HSP 70, NF-${\kappa}$B, COX-1, COX-2 and iNOS. Results : In terms of immunohistochemical changes, the distribution of COX-1 in mice treated with GHS increased noticeably more than that in the pathological group. The distributions of HSP70, NF-${\kappa}$B, COX-2, iNOS in mice treated with GHS more decreased than those in the pathological group. Regeneration of surface epithelial cell and goblet cell in mucosa was observed by optical microscope. The colonic lengths in GHS-treated mice were more elongated than those of DSS only treated mice. Conclusion : GHS is a candidate treatment for ulcerative colitis.

• Journal of the Optical Society of Korea
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• v.17 no.1
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• pp.91-96
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• 2013

We report a method for optical monitoring of tumors in an animal model using optical coherence tomography (OCT). In a spectral domain OCT system, a superluminescent diode light source with a full width of 66 nm at half maximum and peak wavelength of 950 nm was used to take images having an axial resolution of 6.8 ${\mu}m$. Cancer cells of PC-3 were cultured and inoculated into the hypodermis of auricle tissues in BALB/c nude mice. We observed tumor formation and growth at the injection region of cancer cells in vivo and obtained the images of tumor mass center and sparse circumferences. On the $5^{th}$ day from an inoculation of cancer cells, histological images of the tumor region using cross-sectional slicing and dye staining of specimens were taken in order to confirm the correlation with the high resolution OCT images. The OCT image of tumor mass compared with normal tissues was analyzed using its A-scan data so as to obtain a tissue attenuation rate which increases according to tumor growth.

• Proceedings of the Optical Society of Korea Conference
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• 2008.07a
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• pp.159-160
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• 2008

We measured hemodynamic responses of seizure in the mouse brain using frequencydomain near infrared spectroscopy (NIRS) and electroencephalogram (EEG). We adapted microfabricated optical holder for consistent contact of the optical fiber to the mouse brain. Our results show that the cerebral oxygenation and hemodynamics of mice can be stably monitored with EEG in the mouse brain.