Small Size Objects Research Articles

Development of an Anthropomorphic Gripping Manipulator: The Study of Kinematics and Virtual Modeling of Grip

The article is a study into the kinematic scheme of a newly developed anthropomorphic manipulator designed to perform gripping and holding tasks on items from a predefined set. Within the study is the implementation of a mathematical model describing the kinematics of a multilink manipulator using the GraspIt package. The method used in this study allows for the calculation of design parameters for manipulator grip functions at an early stage of the creation process as well as to verify the effectiveness of the kinematic scheme of the manipulator on how adequately it can perform its primary functions of griping and holding certain objects, which is vitally important in the design of universal anthropomorphic handling manipulators for special applications, such as bionic prostheses as well as manipulators with arbitrary kinematic schemes. The presented program model provides a preliminary calculation of the motion trajectories of the manipulator unit through the so-called eigengrasp (synonym-synergy, synchronous motion) and can be used as a virtual model for building embedded control systems for robot manipulators. It is shown that in the development of anthropomorphic handling manipulators for operating with small-sized objects it is more efficient to use the monkey scheme, but if the main group of target objects is primarily large items, then it is better to use the human scheme.

一种UHF频段RFID近场环形标签天线设计

本文设计了一款应用于UHF频段的RFID近场环形标签天线。该天线通过相邻弯折导线间的反向电流削弱环形结构带来的强感抗，有利于实现阻抗匹配和提升带宽；利用向内弯折结构有效的缩减了天线尺寸，可应用于小尺寸物体追踪识别。最终天线印制在FR-4介质板上，尺寸为7.9 × 10.2 × 0.2 mm3，相比同类型天线缩减了42.1%。仿真与测试结果表明天线在近场区域有很好的性能，可应用在UHF RFID系统。 A near-field loop tag antenna for UHF RFID system is proposed. By reverse current from bending adjacent wires to weaken the strong inductive from loop antenna, it’s good for impedance matching and bandwidth promoting; the antenna size can be reduced effectively by the inward bent structure, which can be applied to the small size object tracking identification. The antenna is printed onto the FR-4 substrate, with an overall size of 7.9 × 10.2 × 0.2 mm3, compared to the same type, size of the antenna is reduced to 42.1%. The simulation and test results show that the antenna has a good performance in the near-field region, which can be used in UHF RFID systems.

Algorithm of image reconstruction in the problem of object detection during circular microscanning

A model of image recording in the circular microscanning regime is considered. An algorithm that allows obtaining an image with a large number of samples from a set of smaller-size frames for a known path of the scanning array is proposed. Numerical simulations are performed to estimate the changes in the amplitude of a small-size object with a static position of the photodetector array and microscanning in the start/stop mode. The influence of the gap between the array elements and scanning radius on the object amplitude is studied. The final ratio of the object amplitude to the random noise level in the case of static accumulation and circular microscanning in the start/stop mode are compared for arrays with different sizes of the gap between the array elements.

Molecular dynamics in the examination of the atomic structure of small-sized metallic objects

The present review details the results of studies that showcase the capacity of the molecular dynamics method to analyze the atomic structure of small-sized metallic objects: nanoparticles, thin films, and film heterostructures.

Система управління процесом неперервного сортування малогабаритних об’єктів із застосуванням оптичного тривимірного сортування

This paper we propose a method for three-dimensional scanning, reading and analysis of small-sized physical objects for their further sorting. This technique is based on the principle of generation of free charge carriers under the influence of photons. To read the dimensions of the object used Linear CCD sensors, operating on the principle of contour-raying the object. Analysis of the overall size of the objects and the formation of the reporting form on the implementation of the volumes of the sort carried out by applying a micro-computer. On the basis of the proposed method is based prototyping installation, which consists of the tape unit, the scan engine and control system with digital interface and performs drawing, scanning and recognition of typical objects. Experimentally achieve 50 scans per second small objects up to 12 microns. Information allows us to analyze its volume parameters and evaluate mass characteristics.

Development of control means of geometrical parameters of small-size objects with complex shape

At the present stage of development of science and technology it is made manufacturing high-precision and small-sized parts. Great emphasis in the manufacture of parts is attended to monitoring their parameters. But there is a problem of the geometric parameters of objects of small-sized parts with complex shape, as a feature of its images is large blur and low contrast due to the inability to complete fixing and guidance of acuity In this paper, it is proposed the method of visualization and control of geometric parameters of small-sized objects with complex shape, the advantage of which is the recalculation of dimensions of the object for its sub-pixel coordinates in the blurred image. Also it is proposed a mean of controlling the geometrical parameters of small-sized objects with complex shape, which is based on the proposed method, the feature of which is the probe introduction in the measuring zone with known dimensions, to determine the ratio for conversion of coordinates.

Fast Multiclass Vehicle Detection on Aerial Images

Detecting vehicles in aerial images provides important information for traffic management and urban planning. Detecting the cars in the images is challenging due to the relatively small size of the target objects and the complex background in man-made areas. It is particularly challenging if the goal is near-real-time detection, i.e., within few seconds, on large images without any additional information, e.g., road database and accurate target size. We present a method that can detect the vehicles on a 21-MPixel original frame image without accurate scale information within seconds on a laptop single threaded. In addition to the bounding box of the vehicles, we extract also orientation and type (car/truck) information. First, we apply a fast binary detector using integral channel features in a soft-cascade structure. In the next step, we apply a multiclass classifier on the output of the binary detector, which gives the orientation and type of the vehicles. We evaluate our method on a challenging data set of original aerial images over Munich and a data set captured from an unmanned aerial vehicle (UAV).

Optimal Spatial Filtering Schemes and Compact Tomography Setups

ABSTRACTThree compact computerized tomography (CT) scanner prototypes are established and tested for acceptable reconstruction results. Performance of conventional iterative reconstruction algorithm is enhanced via incorporating a spatial filtering/masking step. Generally, these masking strategies incorporate an arbitrary (3 3 or 2 2) size of square averaging mask to subdue the ill-posedness. Three different spatial filtering schemes are tested in this work. The objective is to remove any dependency on a user for deciding an appropriate masking parameter. The outcome of the simulation study is successfully verified for three real data situations using three specimens with pre-assigned/known inner profile. Such austere scanning situations arise in real-time environment especially for undetachable/fixed small size objects situated in inaccessible locations. The present study encourages the development of low budget CT setups.

Improving the accuracy of GPS compass for small-sized objects

The paper considers determination of attitude parameters, including true heading, by an integrated orientation and navigation system (IONS) comprising MEMS-based inertial measurement unit (IMU) and multiantenna GNSS receiving equipment. IONS generates orientation solution using phase data from two-antenna GNSS module with antenna base about the wavelength of the satellite signal at carrier frequency. The system algorithms and errors are studied. IMU and GNSS antenna base are subjected to modulating rotation. Effectiveness of using GNSS phase determinations for estimating heading errors with a short rotating antenna base is investigated. The system experimental sample uses IMU based on STIM300 Sensonor MEMS sensors (Norway), navigation and phase measurements by GNSS receivers 1K-181 by Russian Institute of Radionavigation and Time (Russia). The results obtained in bench tests are presented.

EXAMINATION ABOUT INFLUENCE FOR PRECISION OF 3D IMAGE MEASUREMENT FROM THE GROUND CONTROL POINT MEASUREMENT AND SURFACE MATCHING

Abstract. As the 3D image measurement software is now widely used with the recent development of computer-vision technology, the 3D measurement from the image is now has acquired the application field from desktop objects as wide as the topography survey in large geographical areas. Especially, the orientation, which used to be a complicated process in the heretofore image measurement, can be now performed automatically by simply taking many pictures around the object. And in the case of fully textured object, the 3D measurement of surface features is now done all automatically from the orientated images, and greatly facilitated the acquisition of the dense 3D point cloud from images with high precision. With all this development in the background, in the case of small and the middle size objects, we are now furnishing the all-around 3D measurement by a single digital camera sold on the market. And we have also developed the technology of the topographical measurement with the air-borne images taken by a small UAV [1~5]. In this present study, in the case of the small size objects, we examine the accuracy of surface measurement (Matching) by the data of the experiments. And as to the topographic measurement, we examine the influence of GCP distribution on the accuracy by the data of the experiments. Besides, we examined the difference of the analytical results in each of the 3D image measurement software. This document reviews the processing flow of orientation and the 3D measurement of each software and explains the feature of the each software. And as to the verification of the precision of stereo-matching, we measured the test plane and the test sphere of the known form and assessed the result. As to the topography measurement, we used the air-borne image data photographed at the test field in Yadorigi of Matsuda City, Kanagawa Prefecture JAPAN. We have constructed Ground Control Point which measured by RTK-GPS and Total Station. And we show the results of analysis made in each of the 3D image measurement software. Further, we deepen the study on the influence of the distribution of GCP on the precision.

Electric discharge during electrosurgery.

Electric discharge utilized for electrosurgery is studied by means of a recently developed method for the diagnostics of small-size atmospheric plasma objects based on Rayleigh scattering of microwaves on the plasma volume. Evolution of the plasma parameters in the near-electrode sheaths and in the positive column is measured and analyzed. It is found that the electrosurgical system produces a glow discharge of alternating current with strongly contracted positive column with current densities reaching 103 A/cm2. The plasma electron density and electrical conductivities in the channel were found be 1016 cm−3 and (1-2) Ohm−1cm−1, respectively. The discharge interrupts every instance when the discharge-driving AC voltage crosses zero and re-ignites again every next half-wave at the moment when the instant voltage exceeds the breakdown threshold.

Comparison of pulse sequences for R1-based electron paramagnetic resonance oxygen imaging

Electron paramagnetic resonance (EPR) spin–lattice relaxation (SLR) oxygen imaging has proven to be an indispensable tool for assessing oxygen partial pressure in live animals. EPR oxygen images show remarkable oxygen accuracy when combined with high precision and spatial resolution. Developing more effective means for obtaining SLR rates is of great practical, biological and medical importance. In this work we compared different pulse EPR imaging protocols and pulse sequences to establish advantages and areas of applicability for each method. Tests were performed using phantoms containing spin probes with oxygen concentrations relevant to in vivo oxymetry. We have found that for small animal size objects the inversion recovery sequence combined with the filtered backprojection reconstruction method delivers the best accuracy and precision. For large animals, in which large radio frequency energy deposition might be critical, free induction decay and three pulse stimulated echo sequences might find better practical usage.

Au nanostructure arrays for plasmonic applications: annealed island films versus nanoimprint lithography.

This paper attempts to compare the main features of random and highly ordered gold nanostructure arrays (NSA) prepared by thermally annealed island film and nanoimprint lithography (NIL) techniques, respectively. Each substrate possesses different morphology in terms of plasmonic enhancement. Both methods allow such important features as spectral tuning of plasmon resonance position depending on size and shape of nanostructures; however, the time and cost is quite different. The respective comparison was performed experimentally and theoretically for a number of samples with different geometrical parameters. Spectral characteristics of fabricated NSA exhibited an expressed plasmon peak in the range from 576 to 809 nm for thermally annealed samples and from 606 to 783 nm for samples prepared by NIL. Modelling of the optical response for nanostructures with typical shapes associated with these techniques (parallelepiped for NIL and semi-ellipsoid for annealed island films) was performed using finite-difference time-domain calculations. Mathematical simulations have indicated the dependence of electric field enhancement on the shape and size of the nanoparticles. As an important point, the distribution of electric field at so-called ‘hot spots’ was considered. Parallelepiped-shaped nanoparticles were shown to yield maximal enhancement values by an order of magnitude greater than their semi-ellipsoid-shaped counterparts; however, both nanoparticle shapes have demonstrated comparable effective electrical field enhancement values. Optimized Au nanostructures with equivalent diameters ranging from 85 to 143 nm and height equal to 35 nm were obtained for both techniques, resulting in the largest electrical field enhancement. The application of island film thermal annealing method for nanochips fabrication can be considered as a possible cost-effective platform for various surface-enhanced spectroscopies; while the NIL-fabricated NSA looks like more effective for sensing of small-size objects.

Processing and Forecasting the Trajectory of a Thrown Object Measured by the Stereo Vision System

Transportation of small-sized rigid objects in industrial environment may be provided by throwing it from the source point and catching it at the destination point. This approach promises better flexibility than traditional transportation systems based on conveyor belts. Accurate real-time forecasting of the object ballistic trajectory is necessary to provide successful catching of the object by the gripper. The development of a sample-based algorithm for trajectory forecasting is a scope of this paper. The input for the forecast is a reference of object spatial coordinates measured by the stereo vision system. Such measurements allow defining the position of the object in a camera-related coordinate system with millimeter accuracy, however they sometimes include outliers. A reference of coordinate transformations is proposed, which translates object coordinates from the camera related 3D system to a 2D system with relations to gravity and motion direction. Outlier detection is made during these transformations. The forecasting is performed in 2D coordinate system with use of k nearest neighbors approach. Applying the algorithm to the measured trajectories showed that it is able to predict future position of the object with 3 centimeters precision in 92 % of cases.

A Longitudinal Study on the Impact of Small-Sized Supporting Objects on Children Behavior

In this study, a preliminary test on 22 Chinese children was conducted. After 11 months, 11 children were successfully re-tested. The results indicated that, whether in body task or object task, children made more scale errors and acts of refusal without reason in the pre-test. Compared with the pre-test, children in the post-test were fully aware of the size of supporting objects, were more likely to refuse with reason, and made active pretending behaviors.

Evaluation of the Impact Count Recovery Model on Standardized Uptake Value Used in PET-CT

Evaluate the effect of lesion size and Sphere to Background Ratio (SBR) on the threshold used for PET tumor volume delineation. Evaluation the effect and the accuracy of Recovery Coefficient (RC) model on Standards Uptake Value (SUV) of different inner size diameters filled with different activity concentration and apply this model on small cohort of patients and construct Look Up Table (LUT) for different lesions with different sizes. A cylindrical phantom equipped with different volume hollow spheres was used. Two different reconstruction algorithms were applied in this study; one of them modified with Point Spread Function (PSF), the other did not based on PSF. Partial volume effect (PVE) was highly dominant in low uptake spheres although it had large size i.e., not only small size object affecting by PVE but also low activity concentration object. For true volume measurements, practically TrueX algorithm was more accurate when activity measurements deal with true or measured volumes. Also, the results showed using that phantom study had successfully provided a practical ‘‘Look Up Table’’ for the partial volume correction of spherical lesions at maximum measured activity ratios that were typically noted in human PET-CT imaging. The present study demonstrated that SBR did not have significant effect on the estimation of volumes from PET images in the different SBRs. The only determining factor for the threshold for PET volume estimation was the size of the sphere. Superior percent accuracy was shown for OSEM algorithm when applying RC model to corrected SUV values and OSEM was more efficient and less error variation with respect to sphere volume, but in case of uncorrected data, no remarkable difference between TrueX and OSEM algorithm had been observed.

Acousto-optic Filtration of Interfering Light Beams for Visualization of Amplitude and Phase Structure of Small-size Objects

A technique for acousto-optic image filtration in full-field interferometry is proposed. It is based on the spectral selection of light in the registration channel of the Michelson interferometer by an imaging acousto-optical tunable filter. The technique is applicable for various full-field spectral-domain systems in profilometry and optical coherence tomography. It is experimentally shown that registered spectral signals may be used for 3-dimensional visualization of structure of optically inhomogeneous objects.

Holographic particle sizing using Wigner–Ville distribution

A novel method for measuring size of small objects with high-aspect ratio from in-line holograms by using Wigner–Ville distribution (WVD) is proposed. The proposed method provides direct calculation of the particle size by using local spatial-frequency information at the half length of holograms being analyzed. Feasibility of this method is experimentally verified by analyzing in-line holograms of an optical fiber.

FAST CLOUD: Pushing the Envelope on Delay Performance of Cloud Storage With Coding

Our paper presents solutions that can significantly improve the delay performance of putting and retrieving data in and out of cloud storage. We first focus on measuring the delay performance of a very popular cloud storage service Amazon S3. We establish that there is significant randomness in service times for reading and writing small and medium size objects when assigned distinct keys. We further demonstrate that using erasure coding, parallel connections to storage cloud and limited chunking (i.e., dividing the object into a few smaller objects) together pushes the envelope on service time distributions significantly (e.g., 76%, 80%, and 85% reductions in mean, 90th, and 99th percentiles for 2-MB files) at the expense of additional storage (e.g., 1.75 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\times$</tex></formula> ). However, chunking and erasure coding increase the load and hence the queuing delays while reducing the supportable rate region in number of requests per second per node. Thus, in the second part of our paper, we focus on analyzing the delay performance when chunking, forward error correction (FEC), and parallel connections are used together. Based on this analysis, we develop load-adaptive algorithms that can pick the best code rate on a per-request basis by using offline computed queue backlog thresholds. The solutions work with homogeneous services with fixed object sizes, chunk sizes, operation type (e.g., read or write) as well as heterogeneous services with mixture of object sizes, chunk sizes, and operation types. We also present a simple greedy solution that opportunistically uses idle connections and picks the erasure coding rate accordingly on the fly. Both backlog-based and greedy solutions support the full rate region and provide best mean delay performance when compared to the best fixed coding rate policy. Our evaluations show that backlog-based solutions achieve better delay performance at higher percentile values than the greedy solution.

The Atlantic ITCZ bias in CMIP5 models

Precipitation over the tropical Atlantic in 24 atmospheric models is analyzed using an object-based approach, which clusters rainy areas in the models as precipitation objects and calculates their properties such as size, amplitude, and location. Based on the distribution of precipitation objects over land and over ocean, two classes of models emerge. The first class of models has a reasonable representation of objects over land but misplaces the ocean object westward, near the coast of Brazil, instead of the central Atlantic as observed. The second class of models show small-sized objects over land with intense precipitation values; for these models, the ocean object is located eastward, near the coast of Guinea. The Atlantic intertropical convergence zone structure in the models exhibits either the West or the East Atlantic bias. No model matches the observed precipitation distribution. The two distinct model behaviors in the mean state are traced to the coastal precipitation bias of the models in boreal spring. In this season, the two model groups place the main precipitation object on opposite coasts—one group puts it at the south coast of Brazil and the other group places it at the Gulf of Guinea. This west–east partitioning of precipitation is sustained in boreal summer, resulting in the West and East Atlantic bias in the annual mean. It is found that models with the East Atlantic bias tend to be high resolution models which rain excessively over the Gulf of Guinea starting from boreal spring.