77,766 research outputs found
Binaries among low-mass stars in nearby young moving groups
The solar galactic neighbourhood contains a number of young co-moving
associations of stars (so-called `young moving groups') with ages of ~10--150
Myr, which are prime targets for a range of scientific studies, including
direct imaging planet searches. The late-type stellar population of such groups
still remain in their pre-main sequence phase, and are thus well suited for
purposes such as isochronal dating. Close binaries are particularly useful in
this regard, since they allow for a model-independent dynamical mass
determination. Here we present a dedicated effort to identify new close
binaries in nearby young moving groups, through high-resolution imaging with
the AstraLux Sur Lucky Imaging camera. We surveyed 181 targets, resulting in
the detection of 61 companions or candidates, of which 38 are new discoveries.
An interesting example of such a case is 2MASS J00302572-6236015 AB, which is a
high-probability member of the Tucana-Horologium moving group, and has an
estimated orbital period of less than 10 years. Among the previously known
objects is a serendipitous detection of the deuterium burning boundary
circumbinary companion 2MASS J01033563-5515561 (AB)b in the z'-band, thereby
extending the spectral coverage for this object down to near-visible
wavelengths.Comment: 12 pages, 3 figures, accepted for publication in A&
Dynamic 3D Urban Scene Modeling Using Multiple Pushbroom Mosaics
In this paper, a unified, segmentation-based approach is proposed to deal with both stereo reconstruction and moving objects detection problems using multiple stereo mosaics. Each set of parallel-perspective (pushbroom) stereo mosaics is generated from a video sequence captured by a single video camera. First a colorsegmentation approach is used to extract the so-called natural matching primitives from a reference view of a pair of stereo mosaics to facilitate both 3D reconstruction of textureless urban scenes and man-made moving targets (e.g. vehicles). Multiple pairs of stereo mosaics are used to improve the accuracy and robustness in 3D recovery and occlusion handling. Moving targets are detected by inspecting their 3D anomalies, either violating the epipolar geometry of the pushbroom stereo or exhibiting abnormal 3D structure. Experimental results on both simulated and real video sequences are provided to show the effectiveness of our approach. 1
TRADE: Object Tracking with 3D Trajectory and Ground Depth Estimates for UAVs
We propose TRADE for robust tracking and 3D localization of a moving target
in cluttered environments, from UAVs equipped with a single camera. Ultimately
TRADE enables 3d-aware target following.
Tracking-by-detection approaches are vulnerable to target switching,
especially between similar objects. Thus, TRADE predicts and incorporates the
target 3D trajectory to select the right target from the tracker's response
map. Unlike static environments, depth estimation of a moving target from a
single camera is a ill-posed problem. Therefore we propose a novel 3D
localization method for ground targets on complex terrain. It reasons about
scene geometry by combining ground plane segmentation, depth-from-motion and
single-image depth estimation. The benefits of using TRADE are demonstrated as
tracking robustness and depth accuracy on several dynamic scenes simulated in
this work. Additionally, we demonstrate autonomous target following using a
thermal camera by running TRADE on a quadcopter's board computer
Coil Gun Turret Control Using A Camera
ABSTRACT --- A conventional weapon usually
by pointing to the target aimed by using hands. It is
considered less effective and efficient in terms of
military service because of spending lots of time to
chase the target. So needed a tool to move the
weapon automatically. This final project present
about object tracking in a weapon and it’s turret,
that will be controlled by camera. The camera is
used to detect moving targets based on a particular
color. In a image sequence consisting of many
different objects, accompanied by a different
background, this system will be able to distinguish
between the target or not. Camera detection is done
by taking moving images with color composition
that has been determined. Then, The image
resolution is resized of the smallest of camera’s
resolutions, that is 320x240. Smaller image size are
intended for the system’s working to be faster.
Capturing image process is use segmentation object
process in digital image processing which aims to
separate the object region with background. The
weapon that will be used, have two degrees of
freedom. Maximum 360 degrees rotation in x axis,
and maximum 90 degrees in y axis. Both of them
using brushed DC motor. At the direction of the y-
axis motion required a gear for transmitting power
between motor shaft and the shaft, so the shaft is
not directly connected to the motor and no
distortion. Turret have been designed had four
buffers as a solid foundation to bear the entire load.
Communication between the camera and weapons
carried out by using the cable. Turret will be
controlled using the PD control which is expected
to reach a position with a quick reference.
Key Words: Object tracking, Digital Image
Processing, Image sequence, PD (Proposional
Deravative) Contro
Automatic aerial target detection and tracking system in airborne FLIR images based on efficient target trajectory filtering
Common strategies for detection and tracking of aerial moving targets in airborne Forward-Looking Infrared
(FLIR) images offer accurate results in images composed by a non-textured sky. However, when cloud and
earth regions appear in the image sequence, those strategies result in an over-detection that increases very
significantly the false alarm rate. Besides, the airborne camera induces a global motion in the image sequence
that complicates even more detection and tracking tasks. In this work, an automatic detection and tracking
system with an innovative and efficient target trajectory filtering is presented. It robustly compensates the
global motion to accurately detect and track potential aerial targets. Their trajectories are analyzed by a curve
fitting technique to reliably validate real targets. This strategy allows to filter false targets with stationary or
erratic trajectories. The proposed system makes special emphasis in the use of low complexity video analysis
techniques to achieve real-time operation. Experimental results using real FLIR sequences show a dramatic
reduction of the false alarm rate, while maintaining the detection rate
Binaries among low-mass stars in nearby young moving groups
The solar galactic neighborhood contains a number of young co-moving associations of stars (known as young moving groups) with ages of ~10–150 Myr, which are prime targets for a range of scientific studies, including direct imaging planet searches. The late-type stellar populations of such groups still remain in their pre-main sequence phase, and are thus well suited for purposes such as isochronal dating. Close binaries are particularly useful in this regard since they allow for a model-independent dynamical mass determination. Here we present a dedicated effort to identify new close binaries in nearby young moving groups, through high-resolution imaging with the AstraLux Sur Lucky Imaging camera. We surveyed 181 targets, resulting in the detection of 61 companions or candidates, of which 38 are new discoveries. An interesting example of such a case is 2MASS J00302572-6236015 AB, which is a high-probability member of the Tucana-Horologium moving group, and has an estimated orbital period of less than 10 yr. Among the previously known objects is a serendipitous detection of the deuterium burning boundary circumbinary companion 2MASS J01033563-5515561 (AB)b in the z′ band, thereby extending the spectral coverage for this object down to near-visible wavelengths
Vision-based detection and tracking of moving target in video surveillance
In this paper a real-time detection and tracking of
moving targets is presented. The scheme involved four phases.
Phase one: Object segmentation which used to identify the
foreground objects from the background by using background
subtraction based on temporal differencing and a rolling-average
background model. Phase two: Object recognition used to
identify the foreground objects that should be tracked by using
simple blob detection. Phase three: Object representation which
takes the outcome from phase two. It computes the
representation of each recognized object to be tracked. Phase 4:
Object tracking that used Kalman filter. The results show that
the tracking system is capable of target shape recovery and
therefore it can successfully track targets with varying distance
from camera or while the camera is zoomin
Aerial moving target detection based on motion vector field analysis
An efficient automatic detection strategy for aerial moving targets in airborne forward-looking infrared (FLIR) imagery is presented in this paper. Airborne cameras induce a global motion over all objects in the image, that invalidates motion-based segmentation techniques for static cameras. To overcome this drawback, previous works compensate the camera ego-motion. However, this approach is too much dependent on the quality of the ego-motion compensation, tending towards an over-detection. In this work, the proposed strategy estimates a robust motion vector field, free of erroneous vectors. Motion vectors are classified into different independent moving objects, corresponding to background objects and aerial targets. The aerial targets are directly segmented using their associated motion vectors. This detection strategy has a low computational cost, since no compensation process or motion-based technique needs to be applied. Excellent results have been obtained over real FLIR sequences
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