Current Issue : January - March Volume : 2018 Issue Number : 1 Articles : 5 Articles
Exact enumeration of aphids before the aphids outbreak can provide basis for precision spray.This paper designs counting software\nthat can be run on smartphones for real-time enumeration of aphids. As a first step of the method used in this paper, images of\nthe yellow sticky board that is aiming to catch insects are segmented from complex background by using GrabCut method; then\nthe images will be normalized by perspective transformation method. The second step is the pretreatment on the images; images\nof aphids will be segmented by using OSTU threshold method after the effect of random illumination is eliminated by single image\ndifference method.Thelast step of the method is aphids� recognition and counting according to area feature of aphids after extracting\ncontours of aphids by contour detection method. At last, the result of the experiment proves that the effect of random illumination\ncan be effectively eliminated by using single image difference method. The counting accuracy in greenhouse is above 95%, while\nit can reach 92.5% outside.Thus, it can be seen that the counting software designed in this paper can realize exact enumeration of\naphids under complicated illumination which can be used widely.The design method proposed in this paper can provide basis for\nprecision spray according to its effective detection insects....
With the advent of intelligent manufacturing, phase measuring deflectometry (PMD) has been widely studied for the measurement of the three-dimensional (3D) shape of specular objects. However, existing PMDs cannot measure objects having discontinuous specular surfaces. This paper presents a new direct PMD (DPMD) method that measures the full-field 3D shape of complicated specular objects. A mathematical model is derived to directly relate an absolute phase map to depth data, instead of the gradient. Two relevant parameters are calibrated using a machine vision-based method. On the basis of the derived model, a full-field 3D measuring system was developed. The accuracy of the system was evaluated using a mirror with known positions along an accurate translating stage. The 3D shape of a monolithic multi-mirror array having multiple specular surfaces was measured. Experimental results show that the proposed DPMD method can obtain the full-field 3D shape of specular objects having isolated and/or discontinuous surfaces accurately and effectively....
Measurements of pressure-sensitive paint (PSP) have been performed using new or\nnon-scientific imaging technology based on machine vision tools. Machine vision camera systems\nare typically used for automated inspection or process monitoring. Such devices offer the benefits\nof lower cost and reduced size compared with typically scientific-grade cameras; however, their\noptical qualities and suitability have yet to be determined. This research intends to show relevant\nimaging characteristics and also show the applicability of such imaging technology for PSP. Details of\ncamera performance are benchmarked and compared to standard scientific imaging equipment and\nsubsequent PSP tests are conducted using a static calibration chamber. The findings demonstrate\nthat machine vision technology can be used for PSP measurements, opening up the possibility of\nperforming measurements on-board small-scale model such as those used for wind tunnel testing or\nmeasurements in confined spaces with limited optical access....
Data fusion is a powerful tool for the merging of multiple sources of information to produce a better output as compared to\nindividual source. This study describes the data fusion of five land use/cover types, that is, bare land, fertile cultivated land, desert\nrangeland, green pasture, and Sutlej basin river land derived fromremote sensing. A novel framework formultispectral and texture\nfeature based data fusion is designed to identify the land use/land cover data types correctly.Multispectral data is obtained using a\nmultispectral radiometer, while digital camera is used for image dataset. It has been observed that each image contained 229 texture\nfeatures, while 30 optimized texture features data for each image has been obtained by joining together three features selection\ntechniques, that is, Fisher, Probability of Error plus Average Correlation, and Mutual Information. This 30-optimized-texturefeature\ndataset is merged with five-spectral-feature dataset to build the fused dataset. A comparison is performed among texture,\nmultispectral, and fused dataset using machine vision classifiers. It has been observed that fused dataset outperformed individually\nboth datasets. The overall accuracy acquired using multilayer perceptron for texture data, multispectral data, and fused data was\n96.67%, 97.60%, and 99.60%, respectively....
In this paper, we present a vision guided robotic ball-beam balancing control\nsystem, consisting of a robot manipulator (actuator), a ball-beam system\n(plant) and a machine vision system (feedback). The machine vision system\nfeedbacks real-time beam angle and ball position data at a speed of 50 frames\nper second. Based on feedback data, the end-effector of a robot manipulator is\ndriven to control the ball position by maneuvering of the inclination angle of\nthe ball-beam system. The overall control system is implemented with two\nFPGA chips, one for machine vision processing, and one for robot joints servo\nPID controllers as well as ball position PD controller. Experiments are performed\non a 5-axes robot manipulator to validate the proposed ball beam balancing\ncontrol system....
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