• Journal of Mechanical Science and Technology
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• 제19권9호
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• pp.1742-1752
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• 2005

This paper presents a Multiple Target Tracking (MTT) Adaptive Cruise Control (ACC) system which consists of three parts; a multi-model-based multi-target state estimator, a primary vehicular target determination algorithm, and a single-target adaptive cruise control algorithm. Three motion models, which are validated using simulated and experimental data, are adopted to distinguish large lateral motions from longitudinally excited motions. The improvement in the state estimation performance when using three models is verified in target tracking simulations. However, the performance and safety benefits of a multi-model-based MTT-ACC system is investigated via simulations using real driving radar sensor data. The MTT-ACC system is tested under lane changing situations to examine how much the system performance is improved when multiple models are incorporated. Simulation results show system response that is more realistic and reflective of actual human driving behavior.

• 한국컴퓨터정보학회논문지
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• 제22권2호
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• pp.37-44
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• 2017

Wireless sensor networks are composed of many wireless sensor nodes that are sensing the environments. These networks have many constraints that are resource constraints, wireless communication, self-construction, etc. But they have many applications that are monitoring environment, tracking the object, etc. In this paper, a mechanism of finding QoS Satisfied multi-path is proposed in wireless sensor networks. In order to satisfy the QoS requirement, the proposed mechanism extends the AODV protocol to find multiple paths from a source node to a destination node by using the additional AODV message types that are proposed. This mechanism will be used to support many QoS applications such as minimum delay time, the better reliability and the better throughput by using the QoS satisfied multi-path. Overheads of the proposed mechanism are evaluated using simulation, and it is showed that QoS satisfied multiple paths are found with a little more overhead than the AODV mechanism.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.177-178
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• 2006

The real-time tracking system is an essential factor for the development of low cost sensor networks for use in pervasive computing and ubiquitous networking. In this paper, we address the interference problems of the sensor network platform with ultrasonic for location tracking system. Ubiquitous indoor environments often contain substantial amounts of metal and other such reflective materials that affect the propagation of radio frequency signals in non-trivial ways, causing severe multi-path effects, dead-spots, noise, and interference. Especially we present a novel reducing interference location system that is particularly well suited to support context-aware computing. The system called Pharos, aims to combine the advantages of real-time tracking systems that implement distributed environment with regardless of infrastructure or infrastructure-less wireless sensor networks.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권9호
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• pp.401-408
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• 2006

In a multi-sensor multi-target tracking systems, the local sensors have the role of tracking the target and transferring the measurements to the fusion center. The measurements from the same target can arrive out of sequence called the out-of-sequence measurements(OOSMs). Out-of-sequence measurements can arise at the fusion center due to communication delay and varying preprocessing time for different sensor platforms. In general, the track fusion occurs to enhance the tracking performance of the sensors using the measurements from the sensors at the fusion center. The target informations can wive at the fusion center with the clutter informations in cluttered environment. In this paper, the OOSM update step with MPDA(Most Probable Data Association) is introduced and tested in several cases with the various clutter density through the Monte Carlo simulation. The performance of the MPDA with OOSM update step is compared with the existing NN, PDA, and PDA-AI for the air target tracking in cluttered and out-of-sequence measurement environment. Simulation results show that MPDA with the OOSM has compatible root mean square errors with out-of-sequence PDA-AI filter and the MPDA is sufficient to be used in out-of-sequence environment.

• 한국정보과학회논문지:시스템및이론
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• 제36권4호
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• pp.274-282
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• 2009

기동물체 추적을 위해서 GPS, INS, 레이더 및 광학장비 등의 다양한 위치추적 센서가 이용되고 있으며, 기동물체의 강인한 추적성능을 유지하기 위해 이기종 센서의 효과적인 융합방법이 필요하다. 이기종 다중센서를 이용한 추적성능 향상을 위해 센서의 서로 다른 오차특성을 고려하여 각 센서의 측정치를 상이한 모델로 간주하여 융합하는 연구가 수행되었지만, 한 센서의 오차가 급격히 증가하는 구간에서 다른 센서의 추정치에 대한 오차가 증가하고 각 센서의 측정값이 참 값일 확률인 Sensor Probability 값에 대해 센서 측정치 변화를 실시간으로 반영하지 못하였다. 본 논문에서는 각 센서 칼만필터의 갱신추정치와 측정치 간의 차이에 대한 RMSE(Root Mean Square Error)를 비교하여 Sensor Probability를 구하고, 결합추정치를 다시 각 센서 칼만필터 입력값으로 대입하는 과정을 제외하여 센서 측정치에 대한 실시간적인 반영과 센서 성능이 급격히 저하되는 구간에서의 추적성능을 개선한다. 제안하는 알고리즘은 각 센서의 오차특성을 조건부 확률값으로 추가하여 각 센서의 Sensor Probability에 따라 가장 양호한 성능을 보이는 센서 위주로 트랙융합을 함으로써 강인성을 보장 한다. 실험을 통해 UAV의 기동 경로를 생성하고 제안 알고리즘을 적용하여 다른 융합 알고리즘과 성능분석을 실시한다.

• 한국멀티미디어학회논문지
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• 제24권3호
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• pp.355-372
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• 2021

Recently, high-performance HMDs (Head-Mounted Display) are becoming wireless due to the growth of virtual reality technology. Accordingly, environmental constraints on the hardware usage are reduced, enabling multiple users to experience virtual reality within a single space simultaneously. Existing multi-user virtual reality platforms use the user's location tracking and motion sensing technology based on vision sensors and active markers. However, there is a decrease in immersion due to the problem of overlapping markers or frequent matching errors due to the reflected light. Goal of this study is to develop a multi-user virtual reality moving platform in a single space that can resolve sensing errors and user immersion decrease. In order to achieve this goal hybrid sensing technology was developed, which is the convergence of vision sensor technology for position tracking, IMU (Inertial Measurement Unit) sensor motion capture technology and gesture recognition technology based on smart gloves. In addition, integrated safety operation system was developed which does not decrease the immersion but ensures the safety of the users and supports multimodal feedback. A 6 m×6 m×2.4 m test bed was configured to verify the effectiveness of the multi-user virtual reality moving platform for four users.

• 한국항공운항학회지
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• 제25권4호
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• pp.83-90
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• 2017

Unmanned Aerial Vehicles(UAVs) require collision avoidance capabilities equivalent to the capabilities of manned aircraft to enter the airspace of manned aircraft. In the case of Visual Flight Rules of manned aircraft, collision avoidance is performed by 'See-and-Avoid' of pilots. To obtain those capabilities of UAVs named as 'Sense-and-Avoid', sensor-system-based intruder tracking and collision avoidance methods are required. In this study, a multi-sensor-based tracking, data fusion, and collision avoidance algorithm is designed by using a model-based design tool MATLAB/SIMULINK, and validations of the designed model and code using numerical simulations and processor-in-the-loop simulations are performed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.43-44
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• 2012

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.121.3-121
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• 2001

The movement of a ship is important for DBS(Direct Broadcasting Satellite) Receiving Antenna control algorithm design on shipboard. Especially, turning of ship is essential factor to affect the angle change of azimuth and elevation. Therefore, to track the satellite stably, we need the tracking method considering turning rate of ship. In this paper, we propose an effective satellite tracking algorithm for DBS receiving antenna on shipboard. In the proposed method, when a ship is turned, it selects one of the Multi tracking modes - Normal mode, Low speed mode, Middle speed mode and High speed mode - according as turning rate to be calculated by using Gyro sensor.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.795-800
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• 2008

The paper presents research for the established experiment environment of multi vehicle robot, localization algorithm that is based on vehicle control, and path tracking. The established experiment environment consists of ultrasonic positioning system, vehicle robot, server and wireless module. Ultrasonic positioning system measures positioning for using ultrasonic sensor and generates many errors because of the influence of environment such as a reflection of wall. For a solution of this fact, localization algorithm is proposed to determine a location using vehicle kinematics and selection of a reliable location data. And path tracking algorithm is proposed to apply localization algorithm and LOS, finally, that algorithms are verified via simulation and experimental