Evaluation of Associated Motion Parameters of Descending Moon Impact Probe (MIP) of Chandrayan-1 from Time Sequential Images

This paper studies the measurement of motion parameters of a parachute scanning platform. The movement of a parachute scanning platform has fast rotational velocity and a complex attitude. Therefore, traditional measurement methods cannot measure the motion parameters accurately, and thus fail to satisfy the requirements for the measurement of parachute scanning platform motion parameters. In order to solve these problems, a method for measuring the motion parameters of a parachute scanning platform based on a combination of magnetic and inertial sensors is proposed in this paper. First, scanning motion characteristics of a parachute-terminal-sensitive projectile are analyzed. Next, a high-precision parachute scanning platform attitude measurement device is designed to obtain the data of magnetic and inertial sensors. Then the extended Kalman filter is used to filter and observe errors. The scanning angle, the scanning angle velocity, the falling velocity, and the 2D scanning attitude are obtained. Finally, the accuracy and feasibility of the algorithm are analyzed and validated by MATLAB simulation, semi-physical simulation, and airdrop experiments. The presented research results can provide helpful references for the design and analysis of parachute scanning platforms, which can reduce development time and cost.

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Perceiving Change with Continuity: Morphologic Patterns in the Fossil Record Using an Analogy

The Paleontological Society Special Publications ◽

10.1017/s2475262200014052 ◽

1999 ◽

Vol 9 ◽

pp. 147-154

Author(s):

Warren D. Allmon

Keyword(s):

Fossil Record ◽

Optical Illusions ◽

Sequential Images

The Belgian inventor and scientist Joseph Antoine Ferdinand Plateau (1801-1883) pioneered one of the first devices aimed at making pictures that seemed to move. Plateau studied various optical illusions that seemed to result from the persistence of the image on the retina of the eye after the image had passed from view. In 1832, he built an apparatus consisting of a flat wheel on which were sequential images of a dancer dancing. When the wheel was turned, the dancer was “seen” to execute the dance. Plateau chose a revealing name for his invention. He called it a “phenakistiscope,” meaning “deceitful view” (Figure 1). The images did not move, but they looked like they did.

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Motion blur invariant for estimating motion parameters of medical ultrasound images

Scientific Reports ◽

10.1038/s41598-021-93636-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Barmak Honarvar Shakibaei Asli ◽

Yifan Zhao ◽

John Ahmet Erkoyuncu

Keyword(s):

Image Quality Assessment ◽

Medical Image Analysis ◽

Main Idea ◽

Delta Function ◽

Motion Blur ◽

Ultrasound Images ◽

Medical Ultrasound ◽

Fetal Ultrasound ◽

Dirac Delta ◽

Motion Parameters

AbstractHigh-quality medical ultrasound imaging is definitely concerning motion blur, while medical image analysis requires motionless and accurate data acquired by sonographers. The main idea of this paper is to establish some motion blur invariant in both frequency and moment domain to estimate the motion parameters of ultrasound images. We propose a discrete model of point spread function of motion blur convolution based on the Dirac delta function to simplify the analysis of motion invariant in frequency and moment domain. This model paves the way for estimating the motion angle and length in terms of the proposed invariant features. In this research, the performance of the proposed schemes is compared with other state-of-the-art existing methods of image deblurring. The experimental study performs using fetal phantom images and clinical fetal ultrasound images as well as breast scans. Moreover, to validate the accuracy of the proposed experimental framework, we apply two image quality assessment methods as no-reference and full-reference to show the robustness of the proposed algorithms compared to the well-known approaches.

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Determining 3-D motion parameters of a rigid body

ACM SIGGRAPH Computer Graphics ◽

10.1145/988525.988541 ◽

1984 ◽

Vol 18 (1) ◽

pp. 25-25

Author(s):

B. L. Yen ◽

T. S. Huang

Keyword(s):

Rigid Body ◽

Motion Parameters

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Analysis of Fabric Shape Style Evaluation Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1048.173 ◽

2014 ◽

Vol 1048 ◽

pp. 173-177 ◽

Cited By ~ 1

Author(s):

Ying Mei Wang ◽

Yan Mei Li ◽

Wan Yue Hu

Keyword(s):

Image Processing ◽

High Speed ◽

Evaluation Method ◽

Contact Method ◽

Ccd Cameras ◽

Point Matching ◽

Feature Point Matching ◽

Motion Parameters ◽

Measurement And Evaluation ◽

Main Factor

Fabric shape style is one of the most important conditions in textile appearance evaluation, and also the main factor influences customer purchasing psychology. At first, the previous fabric shape style evaluation methods are classified and summarized, measurement and evaluation method discussed from tactic and dynamic aspects. Then, companied with computer vision principle, a non-contact method for measuring fabric shape style was put forward. In this method, two high-speed CCD cameras were used to capture fabric movement dynamically, fabric sequences image were obtained in this process. Used the image processing technology include pretreatment and feature point matching to get 3D motion parameters, it can provide data supports for shape style evaluation.

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