• Title/Summary/Keyword: global motion

Search Result 498, Processing Time 0.025 seconds

UAV Auto Pilot System Development with GPS & Infrared Heat sensor (GPS와 적외선 열 센서를 이용한 무인항공기 자동비행 시스템 개발)

  • Choi, Jin-Won;Moon, Jung-Ho;Park, Wook-Je;Chang, Jae-Won
    • Journal of Advanced Navigation Technology
    • /
    • v.9 no.1
    • /
    • pp.28-33
    • /
    • 2005
  • In this paper, we developed the algorithm to control longitudinal and lateral motion of UAV(Unmanned Aerial Vehicle) with Infrared heat sensors and GPS(Global Positioning System) receiver. UAV was controlled to be flown horizontally and also turned coordinately maintaining the constant altitude. Accomplishing the flight test of UAV sevral times, we were able to develope low price controller to control bank angle for lateral motion, and also pitch angle and altitude for longitudinal motion simultaneously.

  • PDF

HI LINEWIDTHS, ROTATION VELOCITIES AND THE TULLY-FISHER RELATION

  • Rhee, Myung-Hyun;Broeils, Adrick H.
    • Journal of Astronomy and Space Sciences
    • /
    • v.22 no.2
    • /
    • pp.89-112
    • /
    • 2005
  • We determine the rotation velocities of 108 spiral and irregular galaxies (XV-Sample) from first-order rotation curves from position-velocity maps, based on short 21-cm observations with the Westerbork Synthesis Radio Telescope (WSRT). To test the usual random motion corrections, we compare the global HI linewidths and the rotation velocities, obtained from kinematical fits to two-dimensional velocity fields for a sample of 28 galaxies (RC-Sample), and find that the most frequently used correction formulae (Tully & Fouque 1985) are not very satisfactory. The rotation velocity parameter (the random-motion corrected HI linewidth: W?), derived with these corrections, may be statistically equal to two times the true rotation velocity, but in individual cases the differences can be large. We analyse, for both RC- and XV-Samples, the dependence of the slope of, and scatter in the Tully-Fisher relation on the definition of the rotation velocity parameters- For the RC-Sample, we find that the scatter in the Tully-Fisher relation can be reduced considerably when the rotation velocities derived from rotation curves are used instead of the random-motion corrected global H I linewidths. No such reduction in the scatter is seen for XV-Sample. We conclude that the reduction of the scatter in the Tully-Fisher relation seems to be related to the use of two-dimensional velocity information: accurate rotation velocity and kinematical inclination.

Motion Planning for Mobile Robots Using a Spline Surface

  • Kato, Kiyotaka;Tanaka, Jyunichi;Tokunaga, Hironori
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.1054-1059
    • /
    • 2005
  • The artificial potential method uses a potential field to guide a robot from a start to a goal configuration respectively. The potential field consists of attractive potential used to pull a robot toward a goal and repulsive potential to keep it away from obstacles. However, there are two problems concerning local minimum and computational cost to be resolved in conventional artificial potential methods. This study proposes a method utilizing a spline surface that interpolates arbitrary boundaries and a domain reduction method that reduces the unnecessary area. The proposed spline surface interpolates arbitrary shaped boundaries and is used as an artificial potential to guide a robot for global motion planning of a mobile robot. A reduced domain process reduces the unnecessary domain. We apply a distance-weighted function as such a function, which blends distances from each boundary with a reduction in computational time compared with other analytical methods. As a result, this paper shows that an arbitrary boundary spline surface provides global planning and a domain reduction method reduces local minimum with quick operation.

  • PDF

Mobile Robot Navigation based on Global DWA with Optimal Waypoints (최적 경유점을 갖는 전역 DWA에 기반한 이동로봇의 주행)

  • Ham, Jong-Gyu;Park, Joong-Tae;Song, Jae-Bok
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.13 no.7
    • /
    • pp.624-630
    • /
    • 2007
  • The dynamic window approach(DWA) is a well known technique for reactive collision avoidance. It shows safe and efficient performance in real-world experiments. However, a robot can get stuck in local minima because no information about the connectivity of the free space is used to determine the motion. The global DWA can solve this problem of local minima by adding a navigation function. Even with the global DWA, it is still difficult for a robot to execute an abrupt change in its direction, for example, entering from the corridor to a doorway. This paper proposes a modified global DWA using the included angles of waypoints extracted from an optimal path. This scheme enables the robot to decelerate in advance before turning into the doorway. Therefore the robot can reach the goal position more safely and efficiently at high speeds.

Scene-based Nonuniformity Correction Complemented by Block Reweighting and Global Offset Initialization

  • Hong, Yong-hee;Lee, Keun-Jae;Kim, Hong-Rak;Jhee, Ho-Jin
    • Journal of the Korea Society of Computer and Information
    • /
    • v.22 no.8
    • /
    • pp.15-23
    • /
    • 2017
  • In this paper, the block reweighting and global offset initialization methods are proposed to complement the improved IRLMS algorithm which is the effective algorithm in registration based SBNUC algorithm. Proposed block weighting method reweights the error map whose abnormal data are excluded. The global offset initialization method compensates the global nonuniformity initially. The ordinary registration based SBNUC algorithm is hard to compensate global nonuniformity because of low scene motion. We employ the proposed methods to improved IRLMS algorithm, and apply it to real-world infrared raw image stream. The result shows that new implementation provides 3.5~4.0dB higher PSNR and convergence speed 1.5 faster then the improved IRLMS algorithm.

Fast Motion Estimation Algorithm using Temporal Continuity of Motion Vector (움직임 벡터의 시간적 연속성을 이용한 고속 움직임 추정 알고리즘)

  • 이경환;류권열;최정현
    • Journal of Korea Multimedia Society
    • /
    • v.6 no.7
    • /
    • pp.1121-1130
    • /
    • 2003
  • This paper proposes a new motion estimation algorithm using the temporal continuity of motion. We set up a wide global search region (GSR), which basically corresponds to the search region of FSA, and local search regions (LSRs), the positions for which are predicted by the motion vectors of the temporal neighbor blocks, are constructed in the GSR. The previous frame blocks that possibly have effects on the current block are to be the temporal neighbor blocks. Then Motion estimation is only performed in the areas made by LSRs. Experimental results show that the proposed method can maintain visual qualifies with significant reductions of complexity by reducing search regions, when compared to the conventional FSA.

  • PDF

Extended kernel correlation filter for abrupt motion tracking

  • Zhang, Huanlong;Zhang, Jianwei;Wu, Qinge;Qian, Xiaoliang;Zhou, Tong;FU, Hengcheng
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.11 no.9
    • /
    • pp.4438-4460
    • /
    • 2017
  • The Kernelized Correlation Filters (KCF) tracker has caused the extensive concern in recent years because of the high efficiency. Numerous improvements have been made successively. However, due to the abrupt motion between the consecutive image frames, these methods cannot track object well. To cope with the problem, we propose an extended KCF tracker based on swarm intelligence method. Unlike existing KCF-based trackers, we firstly introduce a swarm-based sampling method to KCF tracker and design a unified framework to track smooth or abrupt motion simultaneously. Secondly, we propose a global motion estimation method, where the exploration factor is constructed to search the whole state space so as to adapt abrupt motion. Finally, we give an adaptive threshold in light of confidence map, which ensures the accuracy of the motion estimation strategy. Extensive experimental results in both quantitative and qualitative measures demonstrate the effectiveness of our proposed method in tracking abrupt motion.

Binary Hashing CNN Features for Action Recognition

  • Li, Weisheng;Feng, Chen;Xiao, Bin;Chen, Yanquan
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.12 no.9
    • /
    • pp.4412-4428
    • /
    • 2018
  • The purpose of this work is to solve the problem of representing an entire video using Convolutional Neural Network (CNN) features for human action recognition. Recently, due to insufficient GPU memory, it has been difficult to take the whole video as the input of the CNN for end-to-end learning. A typical method is to use sampled video frames as inputs and corresponding labels as supervision. One major issue of this popular approach is that the local samples may not contain the information indicated by the global labels and sufficient motion information. To address this issue, we propose a binary hashing method to enhance the local feature extractors. First, we extract the local features and aggregate them into global features using maximum/minimum pooling. Second, we use the binary hashing method to capture the motion features. Finally, we concatenate the hashing features with global features using different normalization methods to train the classifier. Experimental results on the JHMDB and MPII-Cooking datasets show that, for these new local features, binary hashing mapping on the sparsely sampled features led to significant performance improvements.

Hull/Mooring/Riser Coupled Dynamic Analysis of a Turret-Moored FPSO Compared with OTRC Experiment

  • Kim Young-Bok;Kim Moo-Hyun
    • Journal of Ship and Ocean Technology
    • /
    • v.8 no.3
    • /
    • pp.26-39
    • /
    • 2004
  • A vessel/mooring/riser coupled dynamic analysis program in time domain is developed for the global motion simulation of a turret-moored, tanker based FPSO designed for 6000-ft water depth. The vessel global motions and mooring tension are simulated for the non-parallel wind-wave-current 100-year hurricane condition in the Gulf of Mexico. The wind and current forces and moments are estimated from the OCIMF empirical data base for the given loading condition. The numerical results are compared with the OTRC(Offshore Technology Research Center: Model Basin for Offshore Platforms in Texas A&M University) 1:60 model-testing results with truncated mooring system. The system's stiffness and line tension as well as natural periods and damping obtained from the OTRC measurement are checked through numerically simulated static-offset and free-decay tests. The global vessel motion simulations in the hurricane condition were conducted by varying lateral and longitudinal hull drag coefficients, different mooring and riser set up, and wind-exposed areas to better understand the sensitivity of the FPSO responses against empirical parameters. It is particularly stressed that the dynamic mooring tension can be greatly underestimated when truncated mooring system is used.

Analysis of instrument exercise using IMU about symmetry

  • Yohan Song;Hyun-Bin Zi;Jihyeon Kim;Hyangshin Ryu;Jaehyo Kim
    • International Journal of Advanced Culture Technology
    • /
    • v.11 no.1
    • /
    • pp.296-305
    • /
    • 2023
  • The purpose of this study is to measure and compare the balance of motion between the left and right using a wearable sensor during upper limb exercise using an exercise equipment. Eight participants were asked to perform upper limb exercise using exercise equipment, and exercise data were measured through IMU sensors attached to both wrists. As a result of the PCA test, Euler Yaw(Left: 0.65, Right: 0.75), Roll(Left: 0.72, Right: 0.58), and Gyro X(Left: 0.64, Right: 0.63) were identified as the main components in the Butterfly exercise, and Euler Pitch(Left: 0.70, Right 0.70) and Gyro Z(Left: 0.70, Right: 0.71) were identified as the main components in the Lat pull down exercise. As a result of the Paired-T test of the Euler value, Yaw's Peak to Peak at Butterfly exercise and Roll's Mean, Yaw's Mean and Period at Lat pull down exercise were smaller than the significance level of 0.05, proving meaningful difference was found. In the Symmetry Index and Symmetry Ratio analysis, 89% of the subjects showed a tendency of dominant limb maintaining relatively higher angular movement performance then non-dominant limb as the Butterfly exercise proceeds. 62.5% of the subjects showed the same tendency during the Lat pull down exercise. These experimental results indicate that meaningful difference at balance of motion was found according to an increase in number of exercise trials.