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Estimation of Relative Distance from Surrounding Buildings |
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SungJin Kang, Hyung Keun Lee(Korea Aerospace University, Republic of Korea) |
| The existing GNSS (Global Navigation Satellite System) has the weakness in availability and continuity for the vehicles in urban area since the number of visible satellites decreases abruptly due to large buildings and other structures. In this paper, a new method is proposed to estimate the relative lateral distance of a vehicle from surrounding buildings by a vision sensor to supplement the shortage of satellite-based positioning. |
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Analysis of laser focusing device to improve sensor node positioning performance in optics-based WSN |
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Hyun Cheol Jeon, Chan Gook Park(Seoul National University, Republic of Korea) |
| It is proposed that a method to improve sensor node positioning performance in optics-based WSN. As a method to position the sensor node, ToF and direction angle between base-station and sensor node are used. The problem in this system is that the intensity of the laser decreases as it propagates forward because of divergence angle and that the reflect area of MEMS CCR is too small to reflect enough power. In this paper, the beam propagation function was derived and the simulation was conducted. By introducing the convergent beam, it was resolved that the problem of weak intensity. |
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Development of a Robust Attitude Determination System for a Nano-satellite |
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Chul Woo Kang, Ji Hyun Park, In-Seuck Jeung, Chan Gook Park(Seoul National University, Republic of Korea) |
| In this paper, robust attitude determination based on the indirect extended Kalman filter is proposed. For the nano-satellite, there are only two vectors of magnetic vector and sun vector for vector measurement without redundant sensors. Accordingly, the three-axis attitude determination using conventional algorithm is impossible when one of the vectors is not available. The proposed attitude determination method uses propagation based on satellite attitude dynamics. The gyro measurements are used for a measurement, and angular rates are estimated by measurements and control inputs. |
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Development of a Piezoresistive MEMS Pressure Sensor for a Precision Air Data Module |
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Jang-sub Lee, Eun-Shil Yoo, Chi-hyun Park(Microinfinity Co., Ltd., Republic of Korea), Jun-Eon An(Agency for Defense Development, Republic of Korea), Chan Gook Park, Jin Woo Song(Seoul National University, Republic of Korea) |
| A differential pressure senor for an ADM should cover wide pressure range with less than 1% accuracy. For satisfying these requirements, the p-type piezoresistors with Wheatstone bridge configuration on the silicon diaphragm is used. The resistors are implanted under high doping concentration level for smaller temperature sensitivity, and resistors with same shape and the constant driving current is adopted for error compensation. The repeatability, nonlinearity, and pressure hysteresis are less than 0.09%, 0.27%, and 0.63%, which contributes to RSS accuracy of 0.69%. |
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Reducing the Computation Time in the State Chi-Square Test for IMU Fault Detection |
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Se Hyun YUN, Chul Woo Kang, Chan Gook Park(Seoul National University, Republic of Korea) |
| This paper introduces a hierarchical structure of filters and proposes the state chi-square test (SCST) with newly modified propagator for detecting an accelerometer and gyro fault. All filters in the hierarchical structure of filters include the inertial navigation system (INS) as a common reference system. That is why it is essential to detect the INS fault in the hierarchical structure of filters. The newly modified propagator based on two propagators and N-step propagator is proposed to make up for each weakness. The modified propagator can reduce a fault alarm ratio (FAR) and |
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Collision Avoidance in On-Road Environment for Autonomous Driving |
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Samyeul Noh, Woo-Yong Han(Electronics and Telecommunications Research Institute (ETRI), Republic of Korea) |
| This paper proposes a collision avoidance method in on-road environment for autonomous driving. The proposed method divides a road map into six lane-level regions, assigns risk observers to corresponding regions, evaluates collision risks of situations based on risk observer distribution, and determines collision-free maneuvers to deal with various collision-risky situations. The method was implemented in robot operating system and tested on the closed road with other vehicles to verify that our system operates properly on the road for autonomous driving without collisions. |
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