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– Review of the IMTS show in Chicago with emphasis on the new sensor innovations and applications on display. The paper aims to discuss these issues.
Abstract
Purpose
Review of the IMTS show in Chicago with emphasis on the new sensor innovations and applications on display. The paper aims to discuss these issues.
Design/methodology/approach
In-depth interviews with exhibitors of sensors and sensor integrators at the show.
Findings
Sensors continue to match an ever-increasing number of manufacturing tasks to improve quality and productivity at every step in the manufacturing and inspection process.
Practical implications
Customers may be surprised at the sensor innovations and new applications to which sensors are being applied in the manufacturing environment.
Originality/value
A review of some of the latest sensor innovations and applications that one might have seen if they had been on the exhibition floor at the Chicago IMTS show.
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Keywords
Liang Hu, Chengwei Liu, Rui Su and Weiting Liu
In a coaxial ultrasonic flow sensor (UFS), wall thickness is a vital parameter of the measurement tube, especially those with small inner diameters. The paper aims to investigate…
Abstract
Purpose
In a coaxial ultrasonic flow sensor (UFS), wall thickness is a vital parameter of the measurement tube, especially those with small inner diameters. The paper aims to investigate the influence of wall thickness on the transient signal characteristics in an UFS.
Design/methodology/approach
First, the problem was researched experimentally using a series of measurement tubes with different wall thicknesses. Second, a finite element method–based model in the time domain was established to validate the experimental results and further discussion. Finally, the plane wave assumption and oblique incident theory were used to analyze the wave propagation in the tube, and an idea of wave packet superposition was proposed to reveal the mechanism of the influence of wall thickness.
Findings
Both experimental and simulated results showed that the signal amplitude decreased periodically as the wall thickness increased, and the corresponding waveform varied dramatically. Based on the analysis of wave propagation in the measurement tube, a formula concerning the phase difference between wave packets was derived to characterize the signal variation.
Originality/value
This paper provides a new and explicit explanation of the influence of wall thickness on the transient signal in a co-axial UFS. Both experimental and simulated results were presented, and the mechanism was clearly described.
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A PROPOSAL to replace the 7‐ft. No. 1 wind tunnel at the N.P.L. by two new tunnels of the open jet type, housed in the old tunnel building, was put forward in 1930, and one of the…
Abstract
A PROPOSAL to replace the 7‐ft. No. 1 wind tunnel at the N.P.L. by two new tunnels of the open jet type, housed in the old tunnel building, was put forward in 1930, and one of the new tunnels has now been completed and tested. The present report deals mainly with preliminary experiments on models, which were carried out to ensure that the projected tunnels should give the best possible aerodynamic performance.
Radek Doubrava, Martin Oberthor, Petr Bělský and Bohuslav Cabrnoch
The purpose of this paper is to describe the approach for the design of cowlings for a new fast helicopter from the perspective of airworthiness requirements regarding high-speed…
Abstract
Purpose
The purpose of this paper is to describe the approach for the design of cowlings for a new fast helicopter from the perspective of airworthiness requirements regarding high-speed impact resistance.
Design/methodology/approach
Validated numerical simulation was applied to flat and simple curved test panels. High-speed camera measurement and non-destructive testing (NDT) results were used for verification of the numerical models. The final design was optimized and verified by validated numerical simulation.
Findings
The comparison between numerical simulation based on static material properties with experimental results of high-speed load shows no significant influence of strain rate effect in composite material.
Research limitations/implications
Owing to the sensitivity of the composite material on technology production, the results are limited by the material used and the production technology.
Practical implications
The application of flat and simple curved test panels for the verification and calibration of numerical models allows the optimized final design of the cowling and reduces the risk of structural non-compliance during verification tests.
Originality/value
Numerical models were verified for simulation of the real composite structure based on high-speed camera results and NDT inspection after impact. The proposed numerical model was simplified for application in a complex design and reduced calculation time.
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Keywords
Bing Hua, Zhiwen Zhang, Yunhua Wu and Zhiming Chen
The geomagnetic field vector is a function of the satellite’s position. The position and speed of the satellite can be determined by comparing the geomagnetic field vector…
Abstract
Purpose
The geomagnetic field vector is a function of the satellite’s position. The position and speed of the satellite can be determined by comparing the geomagnetic field vector measured by on board three-axis magnetometer with the standard value of the international geomagnetic field. The geomagnetic model has the disadvantages of uncertainty, low precision and long-term variability. Therefore, accuracy of autonomous navigation using the magnetometer is low. The purpose of this paper is to use the geomagnetic and sunlight information fusion algorithm to improve the orbit accuracy.
Design/methodology/approach
In this paper, an autonomous navigation method for low earth orbit satellite is studied by fusing geomagnetic and solar energy information. The algorithm selects the cosine value of the angle between the solar light vector and the geomagnetic vector, and the geomagnetic field intensity as observation. The Adaptive Unscented Kalman Filter (AUKF) filter is used to estimate the speed and position of the satellite, and the simulation research is carried out. This paper also made the same study using the UKF filter for comparison with the AUKF filter.
Findings
The algorithm of adding the sun direction vector information improves the positioning accuracy compared with the simple geomagnetic navigation, and the convergence and stability of the filter are better. The navigation error does not accumulate with time and has engineering application value. It also can be seen that AUKF filtering accuracy is better than UKF filtering accuracy.
Research limitations/implications
Geomagnetic navigation is greatly affected by the accuracy of magnetometer. This paper does not consider the spacecraft’s environmental interference with magnetic sensors.
Practical implications
Magnetometers and solar sensors are common sensors for micro-satellites. Near-Earth satellite orbit has abundant geomagnetic field resources. Therefore, the algorithm will have higher engineering significance in the practical application of low orbit micro-satellites orbit determination.
Originality/value
This paper introduces a satellite autonomous navigation algorithm. The AUKF geomagnetic filter algorithm using sunlight information can obviously improve the navigation accuracy and meet the basic requirements of low orbit small satellite orbit determination.
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Guoyang Wan, Fudong Li, Wenjun Zhu and Guofeng Wang
The positioning and grasping of large-size objects have always had problems of low positioning accuracy, slow grasping speed and high application cost compared with ordinary small…
Abstract
Purpose
The positioning and grasping of large-size objects have always had problems of low positioning accuracy, slow grasping speed and high application cost compared with ordinary small parts tasks. This paper aims to propose and implement a binocular vision-guided grasping system for large-size object with industrial robot.
Design/methodology/approach
To guide the industrial robot to grasp the object with high position and pose accuracy, this study measures the pose of the object by extracting and reconstructing three non-collinear feature points on it. To improve the precision and the robustness of the pose measuring, a coarse-to-fine positioning strategy is proposed. First, a coarse but stable feature is chosen to locate the object in the image and provide initial regions for the fine features. Second, three circular holes are chosen to be the fine features whose centers are extracted with a robust ellipse fitting strategy and thus determine the precise pose and position of the object.
Findings
Experimental results show that the proposed system has achieved high robustness and high positioning accuracy of −1 mm and pose accuracy of −0.5 degree.
Originality/value
It is a high accuracy method that can be used for industrial robot vision-guided and grasp location.
Details
Keywords
Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory…
Abstract
Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics, and publications of other similar research bodies as issued
Abstract
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The usual method of determining the characteristics of an airscrew by the curves of ? and x as a function of the advance/ diameter ratio neglects the deformations to which an…
Abstract
The usual method of determining the characteristics of an airscrew by the curves of ? and x as a function of the advance/ diameter ratio neglects the deformations to which an airscrew in rotation is subject, and, desiring a more accurate method of investigation, the Service des Recherches de l'Aéronautique asked Commandant Ledoux to work out a method capable of practical application for the measurement of deformations. This report gives in detail the results of his work.
Claims recent advances in laser‐based camera technology and 3D analysis software have made production of 3D CAD models from range images a practical proposition. Laser based…
Abstract
Claims recent advances in laser‐based camera technology and 3D analysis software have made production of 3D CAD models from range images a practical proposition. Laser based cameras must meet very strict design criteria if they are to operate at long ranges; these criteria are explored. High‐speed laser cameras produce vast quantities of image data; it is shown that this data can be converted swiftly into a 3‐D CAD model.
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