scholarly journals Spot Image Segmentation of Lifting Container Vibration Based on Improved Threshold Method and Mathematical Morphology

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Tian-Bing Ma ◽  
Qiang Wu ◽  
Fei Du ◽  
Wei-Kang Hu ◽  
Yong-Jing Ding
Keyword(s):  
Vision System ◽  
Surface Condition ◽  
Research Work ◽  
Vibration Signal ◽  
Structural Vibration ◽  
Threshold Method ◽  
Vibration Displacement ◽  
Threshold Segmentation ◽  
Laser Vision ◽  
Hoisting System

Because the mine is damp and dark, it is not easy to detect the rigid tank channel’s structural failure directly. Therefore, we judged the tank channel’s surface condition by detecting the magnitude of the vibration displacement of the lifting container. In our study, we used a laser vision system to measure the structural vibration displacement. In order to accurately segment the laser spot information from the vibration image, we proposed an approach that links the relationship between the gray value of the area adjacent to the threshold point and the background’s gray value to the target in the image. We used MCE to evaluate the segmentation effect of threshold segmentation and verified the improved algorithm’s accuracy by detecting the pixel centroid of laser spots. Results show that the improved algorithm in our study has the best threshold segmentation effect, the error classification can be close to 0.0003, and the minimum deviation of the obtained vibration displacement is close to 0.1 pixels, which can realize the accurate extraction of the vibration signal of the vertical shaft tank. The novelty of this method lies in the accurate threshold segmentation and noise reduction processing of the laser speck vibration image under various interference environments in the operation of the mine hoisting system and the accurate acquisition of vibration signals. The research work provides a basis for the accurate evaluation of mechanical faults of automation technology.

scholarly journals AutoQual: task-oriented structural vibration sensing quality assessment leveraging co-located mobile sensing context

2021 ◽  
Author(s):  
Yue Zhang ◽  
Zhizhang Hu ◽  
Susu Xu ◽  
Shijia Pan
Keyword(s):  
Task Performance ◽  
Expert Knowledge ◽  
Vibration Signal ◽  
Absolute Error ◽  
Mobile Sensing ◽  
Learning Performance ◽  
Structural Vibration ◽  
Vibration Sensing ◽  
Assessment Approach ◽  
Task Oriented

AbstractIn this paper, we introduce AutoQual, a mobile-based assessment scheme for infrastructure sensing task performance prediction under new deployment environments. With the growth of the Internet-of-Things (IoT), many non-intrusive sensing systems have been explored for various indoor applications, such as structural vibration sensing. This indirect sensing approach’s learning performance is prone to deployment variance when signals propagate through the environment. As a result, current systems heavily rely on expert knowledge and manual assessment to achieve effective deployments and high sensing task performance. In order to mitigate this expert effort, we propose to systematically study factors that reflect deployment environment characteristics and methods to measure them autonomously. We present AutoQual that measures a series of assessment factors (AFs) reflecting how the deployment environment impacts the system performance. AutoQual outputs a task-oriented sensing quality (TSQ) score by integrating measured AFs trained from known deployments as a prediction of untested system’s performance. In addition, AutoQual achieves this assessment without manual effort by leveraging co-located mobile sensing context to extract structural vibration signal for processing automatically. We evaluate AutoQual by using it to predict untested systems’ performance over multiple sensing tasks. We conduct real-world experiments and investigate 48 deployments in 11 environments. AutoQual achieves less than 0.10 average absolute error when auto-assessing multiple tasks at untested deployments, which shows a $$\le 0.018$$ ≤ 0.018 absolute error difference compared to the manual assessment approach.

Research on Machine Vision in Forestry Pluck System

2010 ◽  
Vol 139-141 ◽  
pp. 2199-2202
Author(s):  
Xin Li ◽  
Chun Liang Zhang ◽  
Li Jun Li ◽  
Zhi Hu
Keyword(s):  
Machine Vision ◽  
Vision System ◽  
Area Ratio ◽  
Self Organization ◽  
Machine Vision System ◽  
Camellia Oleifera ◽  
Threshold Method ◽  
Input Feature ◽  
Ga Algorithm ◽  
Forestry Industry

Forestry industry is an important part of nation's economy. In this paper, a machine vision system is presented as a key module of Camellia oleifera pluck robot. In order to cut fruit image up from complicate background, SOFM neural network and gray thresh is used in image segmentation. In SOFM method, take R-B,G-R,G-B and hue H tunnel as input feature vectors, use self-organization network to clustering can get the best effect. in gray threshold method can take various of method to get the best threshold, such as PSO and GA algorithm, and MATLAB includes the toolboxes. At last use noise ratio, area ratio, divided time, Fourier boundary descriptors and other indicators to assess the accuracy of segmentation. The methods have the significance to the current and subsequent research of forestry pluck device.

scholarly journals Wind-Induced Vibration Control of High-Rise Structures Using Compound Damping Cables

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Jianda Yu ◽  
Zhibo Duan ◽  
Xiangqi Zhang ◽  
Jian Peng
Keyword(s):  
Vibration Control ◽  
Damping Ratio ◽  
Viscosity Coefficient ◽  
Structural Vibration ◽  
Vibration Displacement ◽  
High Rise ◽  
Main Cable ◽  
Small Vortex ◽  
Wind Induced Vibration ◽  
Fluctuating Wind

Based on the vibration reduction mechanism of compound damping cables, this study focuses on the wind-induced vibration control of high-rise structures with additional mass at the top. The differential equation of motion of the system under the action of the composite damping cable is established, and the analytical solution of the additional damping ratio of the structure is deduced, which is verified by model tests. The vibration response of the structure under the action of simple harmonic vortex excitation and randomly fluctuating wind loads is studied, and the effect of different viscous coefficients of the dampers in the composite damping cable and different installation heights of the damping cable on the vibration control is analyzed. The results show that a small vortex excitation force will cause large vibrations of low-dampened towering structures, and the structure will undergo buffeting under the action of wind load pulse force. The damping cable can greatly reduce the amplitude of structural vibration. The root means square of structural vibration displacement varies with damping. The viscosity coefficient of the device and the installation height of the main cable of the damping cable are greatly reduced.

Study on Drive Characteristic of Multi–Rope Friction Winder Using Functional Virtual Prototyping

2009 ◽  
Vol 628-629 ◽  
pp. 305-310
Author(s):  
Yi Liu ◽  
Guo Ding Chen ◽  
J.S. Li ◽  
Y.J. Xue
Keyword(s):  
Software Package ◽  
3D Model ◽  
Virtual Work ◽  
Virtual Prototyping ◽  
Research Work ◽  
Three Dimensional ◽  
Virtual Work Principle ◽  
Nodal Method ◽  
Hoisting System ◽  
Dynamics Characteristic

The main objective of this study was to model and simulate a reduced three-dimensional (3D) model for researching the hoisting system of a Multi – rope Friction Winder. By introducing the relative nodal method, the simplified dynamic equations have been derived via the virtual work principle and validated on a virtual prototype with the RecurDyn software package. Kinematics and dynamics characteristic date are obtained by computer-aided dynamic simulation of virtual Multi – rope friction winder. The result is in accord with theoretical analysis. The research work will provide a powerful tool and useful method for the design of economic and credible elevator system. The approach can be generalized to analysis other flexible drive fields.

scholarly journals A Study on Development of Optimal Noise Filter Algorithm for Laser Vision System in GMA Welding

2014 ◽  
Vol 97 ◽  
pp. 819-827 ◽  
Author(s):  
Qian-Qian Wu ◽  
Jong-Pyo Lee ◽  
Min-Ho Park ◽  
Cheol-Kyun Park ◽  
Ill-Soo Kim
Keyword(s):  
Gma Welding ◽  
Vision System ◽  
Noise Filter ◽  
Laser Vision

An Architecture for Distributed Visual Memory

1998 ◽  
Vol 53 (7-8) ◽  
pp. 550-559 ◽  
Author(s):  
Nils Jungclaus ◽  
Markus von der Heyde ◽  
Helge Ritter ◽  
Gerhard Sagerer
Keyword(s):  
Visual Memory ◽  
Vision System ◽  
Research Work ◽  
Semantic Networks ◽  
Memory Architecture ◽  
Natural Systems ◽  
Scientific Disciplines ◽  
Visual Tasks ◽  
Programming Techniques ◽  
Work Done

Abstract The development of autonomous as well as situated robots is one of the great remaining challenges and involves a number of different scientific disciplines. In spite of recent dramatic progress, it remains worthwhile to examine natural systems, because their abilities are still out of reach. Motivated by research work done in the fields of cognitive systems, visual perception, and psychology of memory we designed and implemented a memory architecture for visual tasks. Structural and functional concepts of the memory architecture were modeled on the ones found in natural systems. We present an efficient implementation based on parallel programming techniques. The memory module is integrated into a distributed system for speech and image analysis, which is currently developed in the Sonderforschungsbereich (SFB) 360, Situated Artificial Communicators, where a hybrid vision system combining neural and semantic networks is used.

Denoising in Steel Structural Impulsive Vibration Signal Based on Independent Component Analysis

2011 ◽  
Vol 219-220 ◽  
pp. 1337-1341 ◽  
Author(s):  
Jun Hong Cao ◽  
Zhuo Bin Wei
Keyword(s):  
Independent Component Analysis ◽  
Steel Structure ◽  
Vibration Signal ◽  
Component Analysis ◽  
Independent Component ◽  
Structural Vibration ◽  
Vibration Signals ◽  
Structure Vibration

The analysis of structure vibration signals is influenced by noise mixed in the signals. Independent component analysis (ICA) method is introduced to denoise the vibration signals in this paper. The representative algorithms: FastICA and JADE are told in detail. The algorithms are applied to separate steel structural vibration signals. The denoising performances in impulsive vibration signals generated by steel structure demonstrate the effectiveness and good robustness of ICA method.

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