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This paper aims to investigate the influence of structure parameters on giant-magnetoimpedance (GMI) effect measured by non-contact method.

The GMI sensor contains a Co-based internal magnetic core fabricated by laser cutting and an external solenoid. The influences of magnetic permeability of magnetic core and structure parameters on GMI effect were calculated in theoretical model. The output impedance, resistance, reactance and GMI ratio were measured by non-contact method using impedance analyzer.

Enhancing external magnetic field intensity can decrease the magnetic permeability of core, which has vital influences on the magnetic property and the output response of GMI sensor. In addition, increasing the width of magnetic core and the number of solenoid turns can increase the maximum GMI ratio. The maximum GMI ratio is 3,230% with core width of 6 mm and solenoid turns of 200.

Comparing with traditional contact-measured GMI sensor, the maximum GMI ratio and the magnetic field sensitivity are improved and the power consumption is decreased in non-contact measured GMI sensor. GMI sensor measured by non-contact method has a wide range of potential applications in ultra-sensitive magnetic field detection.

The introduction of time compression technologies into the modern mechanical design process is now well established. Most major automotive and aerospace companies have invested, as have their Tier 1 suppliers. It has been identified that a bottleneck affecting all aspects of the cycle is the measurement process. In this paper we shall discuss potential benefits of adopting non‐contact techniques. In section 1 we discuss the need for rapid physical measurement within the context of the mechanical design process. The processes required for surface creation and inspection are discussed in Section 2 with regard to contact and non‐contact measurement. Section 3 reviews the operating principles of commercially available non‐contact systems. Finally Section 4 discusses practical issues relating to the implementation and use of non‐contact systems in the manufacturing environment.

The paper describes the application of two different vibration measurement methods for the identification of natural modes of the miniature unmanned aerial vehicle (UAV). The purpose of this study is to determine resonant frequencies and modes of mini-airplane within the specified range of frequency values.

Special measuring equipment was used including both contact and non-contact techniques. The measuring systems on equipment of the Institute of Aviation Technology in the Faculty of Mechatronics, Armament and Aerospace of Military University of Technology (Warsaw, PL) were used to conduct measurements. In traditional ground vibration testing (GVT) methods a large number of sensors should be attached to the aircraft. The weight of sensors and cables is negligible in relation to the mass of the large aircraft. However, for small and lightweight unmanned aerial vehicles, this could bring a significant mass component in relation to the total mass of the tested object.

The real mini-UAV construction was used to investigate its resonant modes in the range of frequencies between 0 and 50 Hz. After receiving the output values it is possible to perform some flutter calculations within the range of operational velocities. As there is no certainty that the computed modes are in accordance with those natural ones some parametric calculations are recommended. Modal frequencies depend on structural parameters which are quite difficult to identify. Adopting their values from the reasonable range it is possible to assign the range of possible frequencies. The frequencies of rudder or elevator modes are dependent on their mass moments of inertia and rigidity of controls. The critical speeds of tail flutter were calculated for various combinations of stiffness or mass values.

In this paper, some specific techniques of performing the GVT test were presented. Two different measuring methods were applied, i.e. the contact method and the non-contact method. Using the dedicated apparatus in relation to the mini-airplane, properly prepared in terms of mass distribution, rudders deflection stiffness and proper support, some resonant characteristics can be determined. The contact measuring system consists of a multi-channel analyzer, piezoelectric accelerometers, electrodynamic exciters, amplifiers, impedance heads and a computer with the Test.Lab Software. As the non-contact method, a laser scanning vibrometer was used. The principle of its operation is based on the separation of the emitted laser beam. The returning beam reflected from a vibrating object is captured by the camera and compared to the reference beam. Dedicated software analyzes collected data and on the basis of it creates animations of structural vibrational shapes and spectral plots within the investigated frequency range.

The object used for research is the mini-UAV Rybitwa – composite mini-plane with a classic aerodynamic layout manufactured in Institute of Aviation Technology Military University of Technology. In the work, both measurement methods and some sample results were presented. Results referenced to dynamic properties of the mini-UAV can be applied in the future for its finite element model tuning, what would be useful for the needs of some parametric analyzes in case of some UAV modifications because of its structural or equipment modifications.

This paper aims to propose a non-contact method using machine vision for measuring the surface roughness of a rotating workpiece at speeds of up to 4,000 rpm.

A commercial digital single-lens-reflex camera with high shutter speed and backlight was used to capture a silhouette of the rotating workpiece profile. The roughness profile was extracted at sub-pixel accuracy from the captured images using the moment invariant method of edge detection. The average (Ra), root-mean square (Rq) and peak-to-valley (Rt) roughness parameters were measured for ten different specimens at spindle speeds of up to 4,000 rpm. The roughness values measured using the proposed machine vision system were verified using the stylus profilometer.

The roughness values measured using the proposed method show high correlation (up to 0.997 for Ra) with those determined using the profilometer. The mean differences in Ra, Rq and Rt between the two methods were only 4.66, 3.29 and 3.70 per cent, respectively.

The proposed method has significant potential for application in the in-process roughness measurement and tool condition monitoring from workpiece profile signature during turning, thus, obviating the need to stop the machine.

The machine vision method combined with sub-pixel edge detection has not been applied to measure the roughness of a rotating workpiece.

The conventional strain gauge type pressure sensor suffers in static testing of engines due to the contact transduction method. This paper aims to focus on the concept of non-contact transduction-based pressure sensor using eddy current displacement sensing coil (ECDS) to overcome the temperature limitations of the strain gauge type pressure sensor. This paper includes the fabrication of prototypes of the proposed pressure sensor and its performance evaluation by static calibration. The fabricated pressure sensor is proposed to measure pressure in static test environment for a short period in the order of few seconds. The limitations of the fabricated pressure sensor related to temperature problems are highlighted and the suitable design changes are recommended to aid the future design.

The design of ECDS-based pressure sensor is aimed to provide non-contact transduction to overcome the limitations of the strain gauge type of pressure sensor. The ECDS is designed and fabricated with two configurations to measure deflection of the diaphragm corresponding to the applied pressure. The fabricated ECDS is calibrated using a standard micro meter to ensure transduction within limits. The fabricated prototypes of pressure sensors are calibrated using dead weight tester, and the calibration results are analyzed to select the best configuration. The proposed pressure sensor is tested at different temperatures, and the test results are analyzed to provide recommendations to overcome the shortcomings.

The performance of the different configurations of the pressure sensor using ECDS is evaluated using the calibration data. The analysis of the calibration results indicates that the pressure sensor using ECDS (coil-B) with the diaphragm as target is the best configuration. The accuracy of the fabricated pressure sensor with best configuration is ±2.8 per cent and the full scale (FS) output is 3.8 KHz. The designed non-contact transduction method extends the operating temperature of the pressure sensor up to 150°C with the specified accuracy for the short period.

Most studies of eddy current sensing coil focus on the displacement and position measurement but not on the pressure measurement. This paper is concerned with the design of the pressure sensor using ECDS to realize the non-contact transduction to overcome the limitations of strain gauge type pressure sensors and evaluation of the fabricated prototypes. It is shown that the accuracy of the proposed pressure sensor is not affected by the high temperature for the short period due to non-contact transduction using ECDS.

Today, approximately three years since its development, the non‐contact micro soldering method (local soldering method) continues to be highly regarded due to its superiority over other soldering methods (i.e., soldering irons, etc.) and is being used in a wide range of applications in the industrial electronics field. This technology has been incorporated into the production lines of numerous plants worldwide including the USA and Japan. This paper focuses on introducing the following: (1) the micro spot soldering method, the method most frequently utilised in production lines; (2) the continuous soldering method newly developed for use with surface‐mount components such as connectors of PCMCIA memory cards; and (3) the upward soldering method in which the light beam is irradiated upward, enabling the components to be soldered without flipping printed circuit boards (PCBs). The paper will also include practical examples, the optimal circuit board design, and an evaluation of soldering quality.

The purpose of this paper is to investigate the influence of surface topology on the performance of laser line scanning probe and to suggest methodology for 3D digitization of specular surfaces.

Two different molds, one having milled surface and the other with polished surface, were used to identify effect of surface characteristics on the performance of laser line scanning probe mounted on bridge-type coordinate measuring machine. The point cloud data acquisition of two surfaces was carried out using different combinations of laser scanning parameters. The point cloud sets thus obtained were analyzed in terms of completeness, noise and accuracy. The polished mold which exhibited specular reflection was digitized at different scanning angles of laser line scanning probe using the best combination of scanning parameters.

Results confirmed that surface characteristics play important role to determine quality of the reverse engineering (RE) process. The results in terms of completeness, accuracy and noise for point cloud sets have successfully been obtained for milled and polished surfaces. Three-dimensional (3D) comparison analysis suggested larger deviation in cases of polished surface as compared to milled surface. The point cloud set acquired with proposed approach was better in terms of both completeness and noise reduction.

There has been an increased demand for measurement of metallic, polished and shiny surfaces in automotive, aerospace and medical industries. These surfaces are very difficult to scan because they exhibit specular reflection instead of diffuse reflection. Laser line scanning probe which is a non-contact method is in great demand for RE. This is due to the fact that it possesses very high data acquisition speed. However, laser scanning is hugely affected by surface characteristics which in turn govern specular reflection.In this paper, it has been shown that a surface that exhibits various degrees of specular reflection can be digitized efficiently if appropriate combination of scanning parameters and positions of laser line scanning probe are used. Also, this paper has attempted to offer a procedure to overcome incompleteness and noise in 3D data as obtained by the laser line scanning probe.

The purpose of this paper is to explore a novel breast volume measuring method by mesh projection based on three-dimensional (3D) point cloud data.

Mesh projection method, a rapid and accurate method to calculate the volume of models described by triangular meshes, was transplanted to calculate breast volume based on 3D point cloud data derived from a [TC]2 3D scanner. A simple landmarking procedure was developed to decide breast boundary. Breast volumes derived from mesh projection method were compared to the results of water displacement by statistical analysis to validate its accuracy.

A novel breast volume measurement method is developed based on mesh projection method. By comparison of water displacement, mesh projection method is proved to be accurate to calculate breast volume. Furthermore, a simple and standard breast boundary landmarking procedure is established, which avoids the arbitrariness of the definition of breast boundary and improves the repetition of landmarking.

A simple and convenient tool is provided for bra industries to rapidly and accurately measure breast volume.

Mesh projection method is primarily applied to determine breast volume based on 3D point cloud data. Meanwhile, a simple and standard breast boundary landmarking procedure is put forward.

Marking and inspecting are key steps in hull structure construction. However, currently most marking and inspecting operations are still carried out manually, which leads to low assembly efficiency and quality. This paper aims to solve these problems through the application of digital technology: the optical projection and machine vision.

First, the assembly process model of hull construction is established in 3D design environment. Second, the process information is presented to workers in a virtual form through optical projector, which provides accurate guidance for the manual operation. On this basis, the workers can complete welding and assembly operations readily. Finally, the machine vision method is used to check the assembly results, which can decrease the subjective errors.

A rapid and accurate assembly positioning for hull structure construction is realized based on optical projection, which can avoid the pollution caused by the marking machine and the error caused by human.

This paper combines the advantages of optical projection and machine vision to the field of shipbuilding. The shortcomings of the traditional marking and inspection methods is effectively solved, which may provide a new way for enhancing the assembly efficiency and quality.

Geometric errors are common in metallic bent tubular parts. Thus, tubes should be inspected and fixed before welding with the joints first. After welding, the relative position of the joints is also necessary to be inspected to judge whether the tube can be assembled reliably. Therefore, the inspection plays an important role in the tube’s assembly. The purpose of this paper is to propose a multi-vision-based system designed to inspect the tube and the relative position of the joints.

For the tube inspection, the small cylinders are taken as the primitives to reconstruct the tube using the multi- vision-based system. Then, any geometric error in the tube can be inspected by comparing the reconstructed models and designed ones. For joints’ inspection, authors designed an adapter with marked points, by which the system can calculate the relative position of the joints.

The reconstruction idea can recognise the line and arc segments of a tube automatically and resolve the textureless deficiency of the tube’s surface. The joints’ inspection method is simple in operation, and any kinds of joints can be inspected by designing the structure of the adapters accordingly.

By experimental verification, the inspection precision of the proposed system was 0.17 mm; the inspection time was within 2 min. Thus, the system developed can inspect a tube effectively and automatically. Moreover, authors can determine how the springback of the arcs behaves, allowing in-process springback prediction and compensation, which can reduce geometric errors in the tubes given the present bending machine accuracy.