• Title/Summary/Keyword: 실시간추적

Search Result 1,564, Processing Time 0.034 seconds

Error Compensation Algorithm of CSS-Based Real-Time Location Awareness Systems (CSS기반의 실시간 근거리 위치인식을 위한 위치 보정 기법)

  • Han, Sung-Hoon;Choi, Tae-Wan;Ryu, Dae-Hyun;Shin, Seung-Jung
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.11 no.2
    • /
    • pp.119-126
    • /
    • 2011
  • In this paper, we expect that the IEEE 802.15.4a, which is based on CSS, will be used a lot without getting help from other systems or sensors and will make it possible to measure the distance between radio chips in sensor network field, where the location information of the standard have to be based upon. But, the error rate will be high, so we will correct the location of the tag, which will be received by anchor. The technology of location correction we offer is reducing the error rate through calculating the distance from Compensation Tag, and after that, unite the Toa method with the Fingerprint method and adapt them to location correction technology, calculate the location's estimate, and finally abstract the best suited location estimate for Compensation Tag. At last, we offer developing systems as indoor systems of CSS, which pursue the location between nodes, and a thesis about indoor systems and making their accuracy higher.

Predictive Control for Mobile Robots Using Genetic Algorithms (유전알고리즘을 이용한 이동로봇의 예측제어)

  • Son, Hyun-sik;Park, Jin-hyun;Choi, Young-kiu
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.21 no.4
    • /
    • pp.698-707
    • /
    • 2017
  • This paper deals with predictive control methods of mobile robots for reference trajectory tracking control. Predictive control methods using predictive model are known as effective schemes that minimize the future errors between the reference trajectories and system states; however, the amount of real-time computation for the predictive control are huge so that their applications were limited to slow dynamic systems such as chemical processing plants. Lately with high computing power due to advanced computer technologies, the predictive control methods have been applied to fast systems such as mobile robots. These predictive controllers have some control parameters related to control performance. But these parameters have not been optimized. In this paper we employed the genetic algorithm to optimize the control parameters of the predictive controller for mobile robots. The improved performances of the proposed control method are demonstrated by the computer simulation studies.

Real-time user motion generation and correction using RGBD sensor (RGBD 센서를 이용한 실시간 사용자 동작 생성 및 보정)

  • Gu, Tae Hong;Kim, Un Mi;Kim, Jong Min;Kwon, Tae Soo
    • Journal of the Korea Computer Graphics Society
    • /
    • v.23 no.5
    • /
    • pp.67-73
    • /
    • 2017
  • We propose several techniques which can be employed in a 3D fitness program for monitoring and correcting user's posture. To implement a 3D fitness program, improved reference motion generating techniques and visualizing techniques are necessary. First, in order to understand the difference between the user and the reference movement of a professional, a retargeting method between two different body shapes are studied. Second, the problem of self-occlusion, which occurs when using a low-cost depth sensor to represent complex motions, is solved by using a sample database and time consistency. The system proposed in this paper evaluates the user's posture considering the physical characteristics of the user, and then provides feedback to the user.

Design of a Photo Energy Harvesting Circuit Using On-chip Diodes (온칩 다이오드를 이용한 빛에너지 하베스팅 회로 설계)

  • Yoon, Eun-Jung;Hwang, In-Ho;Park, Jun-Ho;Park, Jong-Tae;Yu, Chong-Gun
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.16 no.3
    • /
    • pp.549-557
    • /
    • 2012
  • In this paper an on-chip photo energy harvesting system with MPPT(Maximum Power Point Tracking) control is proposed. The ISC(Integrated Solar Cell) is implemented using p-diff/n-well diodes available in CMOS processes. MPPT control is implemented using the linear relationship between the open-circuit voltage of a PV(Photovoltaic) cell and its MPP(Maximum Power Point) voltage such that a small pilot PV cell can track the MPP of a main PV cell in real time. Simulation results show that the designed circuit with the MPPT control delivers the MPP voltage to load even though the load is heavy such that the load circuit can operate properly. The proposed circuit is designed in 0.18um CMOS process. The designed main PV cell and pilot PV cell occupy $8mm^2$ and $0.4mm^2$ respectively.

Fuzzy Navigation and Obstacle Avoidance Control for Docking of Modular Robots (모듈형 로봇의 자가 결합을 위한 퍼지 주행 제어 및 장애물 회피 제어)

  • Na, Doo-Young;Noh, Su-Hee;Moon, Hyung-Pil;Jung, Jin-Woo;Kim, Yong-Tae
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.19 no.4
    • /
    • pp.470-477
    • /
    • 2009
  • Modular reconfigurable robots with physical docking capability easily adapt to a new environment and many studies are necessary for the modular robots. In this paper, we propose a vision-based fuzzy autonomous docking controller for the modular docking robots. A modular docking robot platform which performs real-time image processing is designed and color-based object recognition method is implemented on the embedded system. The docking robot can navigate to a subgoal near a target robot while avoiding obstacles. Both a fuzzy obstacle avoidance controller and a fuzzy navigation controller for subgoal tracking are designed. We propose an autonomous docking controller using the fuzzy obstacle avoidance and navigation controllers, absolute distance information and direction informations of robots from PSD sensors and a compass sensor. We verify the proposed docking control method by docking experiments of the developed modular robots in the various environments with different distances and directions between robots.

An Camera Information Detection Method for Dynamic Scene (Dynamic scene에 대한 카메라 정보 추출 기법)

  • Ko, Jung-Hwan
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.50 no.5
    • /
    • pp.275-280
    • /
    • 2013
  • In this paper, a new stereo object extraction algorithm using a block-based MSE (mean square error) algorithm and the configuration parameters of a stereo camera is proposed. That is, by applying the SSD algorithm between the initial reference image and the next stereo input image, location coordinates of a target object in the right and left images are acquired and then with these values, the pan/tilt system is controlled. And using the moving angle of this pan/tilt system and the configulation parameters of the stereo camera system, the mask window size of a target object is adaptively determined. The newly segmented target image is used as a reference image in the next stage and it is automatically updated in the course of target tracking basing on the same procedure. Meanwhile, a target object is under tracking through continuously controlling the convergence and FOV by using the sequentiall extracted location coordinates of a moving target.

A Battery Charger Using Photovoltaic Energy Harvesting with MPPT Control (빛 에너지 하베스팅을 이용한 MPPT 제어 기능을 갖는 배터리 충전기)

  • Yoon, Eun-Jung;Yang, Min-Jae;Yu, Chong-Gun
    • Journal of IKEEE
    • /
    • v.19 no.2
    • /
    • pp.201-209
    • /
    • 2015
  • This paper describes a battery charger using photovoltaic energy harvesting with MPPT control. The proposed circuit harvests maximum power from a PV(photovoltaic) cell by employing MPPT(Maximum Power Point Tracking) control and charges an external battery with the harvested energy. The charging state of the battery is controlled according to the signals from a battery management circuit. The MPPT control is implemented using linear relationship between the open-circuit voltage of a PV cell and its MPP voltage such that a pilot PV cell can track the MPP of a main PV cell in real time. The proposed circuit is designed in a $0.35{\mu}m$ CMOS process technology and its functionality has been verified through extensive simulations. The maximum efficiency of the designed entire system is 86.2% and the chip area including pads is $1.35mm{\times}1.2mm$.

A method of improving the quality of 3D images acquired from RGB-depth camera (깊이 영상 카메라로부터 획득된 3D 영상의 품질 향상 방법)

  • Park, Byung-Seo;Kim, Dong-Wook;Seo, Young-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.25 no.5
    • /
    • pp.637-644
    • /
    • 2021
  • In general, in the fields of computer vision, robotics, and augmented reality, the importance of 3D space and 3D object detection and recognition technology has emerged. In particular, since it is possible to acquire RGB images and depth images in real time through an image sensor using Microsoft Kinect method, many changes have been made to object detection, tracking and recognition studies. In this paper, we propose a method to improve the quality of 3D reconstructed images by processing images acquired through a depth-based (RGB-Depth) camera on a multi-view camera system. In this paper, a method of removing noise outside an object by applying a mask acquired from a color image and a method of applying a combined filtering operation to obtain the difference in depth information between pixels inside the object is proposed. Through each experiment result, it was confirmed that the proposed method can effectively remove noise and improve the quality of 3D reconstructed image.

Design of a Crowd-Sourced Fingerprint Mapping and Localization System (군중-제공 신호지도 작성 및 위치 추적 시스템의 설계)

  • Choi, Eun-Mi;Kim, In-Cheol
    • KIPS Transactions on Software and Data Engineering
    • /
    • v.2 no.9
    • /
    • pp.595-602
    • /
    • 2013
  • WiFi fingerprinting is well known as an effective localization technique used for indoor environments. However, this technique requires a large amount of pre-built fingerprint maps over the entire space. Moreover, due to environmental changes, these maps have to be newly built or updated periodically by experts. As a way to avoid this problem, crowd-sourced fingerprint mapping attracts many interests from researchers. This approach supports many volunteer users to share their WiFi fingerprints collected at a specific environment. Therefore, crowd-sourced fingerprinting can automatically update fingerprint maps up-to-date. In most previous systems, however, individual users were asked to enter their positions manually to build their local fingerprint maps. Moreover, the systems do not have any principled mechanism to keep fingerprint maps clean by detecting and filtering out erroneous fingerprints collected from multiple users. In this paper, we present the design of a crowd-sourced fingerprint mapping and localization(CMAL) system. The proposed system can not only automatically build and/or update WiFi fingerprint maps from fingerprint collections provided by multiple smartphone users, but also simultaneously track their positions using the up-to-date maps. The CMAL system consists of multiple clients to work on individual smartphones to collect fingerprints and a central server to maintain a database of fingerprint maps. Each client contains a particle filter-based WiFi SLAM engine, tracking the smartphone user's position and building each local fingerprint map. The server of our system adopts a Gaussian interpolation-based error filtering algorithm to maintain the integrity of fingerprint maps. Through various experiments, we show the high performance of our system.

Video Analysis System for Action and Emotion Detection by Object with Hierarchical Clustering based Re-ID (계층적 군집화 기반 Re-ID를 활용한 객체별 행동 및 표정 검출용 영상 분석 시스템)

  • Lee, Sang-Hyun;Yang, Seong-Hun;Oh, Seung-Jin;Kang, Jinbeom
    • Journal of Intelligence and Information Systems
    • /
    • v.28 no.1
    • /
    • pp.89-106
    • /
    • 2022
  • Recently, the amount of video data collected from smartphones, CCTVs, black boxes, and high-definition cameras has increased rapidly. According to the increasing video data, the requirements for analysis and utilization are increasing. Due to the lack of skilled manpower to analyze videos in many industries, machine learning and artificial intelligence are actively used to assist manpower. In this situation, the demand for various computer vision technologies such as object detection and tracking, action detection, emotion detection, and Re-ID also increased rapidly. However, the object detection and tracking technology has many difficulties that degrade performance, such as re-appearance after the object's departure from the video recording location, and occlusion. Accordingly, action and emotion detection models based on object detection and tracking models also have difficulties in extracting data for each object. In addition, deep learning architectures consist of various models suffer from performance degradation due to bottlenects and lack of optimization. In this study, we propose an video analysis system consists of YOLOv5 based DeepSORT object tracking model, SlowFast based action recognition model, Torchreid based Re-ID model, and AWS Rekognition which is emotion recognition service. Proposed model uses single-linkage hierarchical clustering based Re-ID and some processing method which maximize hardware throughput. It has higher accuracy than the performance of the re-identification model using simple metrics, near real-time processing performance, and prevents tracking failure due to object departure and re-emergence, occlusion, etc. By continuously linking the action and facial emotion detection results of each object to the same object, it is possible to efficiently analyze videos. The re-identification model extracts a feature vector from the bounding box of object image detected by the object tracking model for each frame, and applies the single-linkage hierarchical clustering from the past frame using the extracted feature vectors to identify the same object that failed to track. Through the above process, it is possible to re-track the same object that has failed to tracking in the case of re-appearance or occlusion after leaving the video location. As a result, action and facial emotion detection results of the newly recognized object due to the tracking fails can be linked to those of the object that appeared in the past. On the other hand, as a way to improve processing performance, we introduce Bounding Box Queue by Object and Feature Queue method that can reduce RAM memory requirements while maximizing GPU memory throughput. Also we introduce the IoF(Intersection over Face) algorithm that allows facial emotion recognized through AWS Rekognition to be linked with object tracking information. The academic significance of this study is that the two-stage re-identification model can have real-time performance even in a high-cost environment that performs action and facial emotion detection according to processing techniques without reducing the accuracy by using simple metrics to achieve real-time performance. The practical implication of this study is that in various industrial fields that require action and facial emotion detection but have many difficulties due to the fails in object tracking can analyze videos effectively through proposed model. Proposed model which has high accuracy of retrace and processing performance can be used in various fields such as intelligent monitoring, observation services and behavioral or psychological analysis services where the integration of tracking information and extracted metadata creates greate industrial and business value. In the future, in order to measure the object tracking performance more precisely, there is a need to conduct an experiment using the MOT Challenge dataset, which is data used by many international conferences. We will investigate the problem that the IoF algorithm cannot solve to develop an additional complementary algorithm. In addition, we plan to conduct additional research to apply this model to various fields' dataset related to intelligent video analysis.