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Existing calibration methods mainly focus on the camera laser-plane calibration of a single laser-line length, which is not convenient and cannot guarantee the consistency of the results when several three-dimensional (3D) scanners are involved. Thus, this study aims to provide a unified step for different laser-line length calibration requirements for laser profile measurement (LPM) systems.

3D LPM is the process of converting physical objects into 3D digital models, wherein camera laser-plane calibration is critical for ensuring system precision. However, conventional calibration methods for 3D LPM typically use a calibration target to calibrate the system for a single laser-line length, which needs multiple calibration patterns and makes the procedure complicated. In this paper, a unified calibration method was proposed to automatically calibrate the camera laser-plane parameters for the LPM systems with different laser-line lengths. The authors designed an elaborate planar calibration target with different-sized rings that mounted on a motorized linear platform to calculate the laser-plane parameters of the LPM systems. Then, the camera coordinates of the control points are obtained using the intersection line between the laser line and the planar target. With a new proposed error correction model, the errors caused by hardware assembly can be corrected. To validate the proposed method, three LPM devices with different laser-line lengths are used to verify the proposed system. Experimental results show that the proposed method can calibrate the LPM systems with different laser-line lengths conveniently with standard steps.

The repeatability and accuracy of the proposed calibration prototypes were evaluated with high-precision workpieces. The experiments have shown that the proposed method is highly adaptive and can automatically calibrate the LPM system with different laser-line lengths with high accuracy.

In the repeatability experiments, there were errors in the measured heights of the test workpieces, and this is because the laser emitter had the best working distance and laser-line length.

By using this proposed method and device, the calibration of the 3D scanning laser device can be done in an automatic way.

The calibration efficiency of a laser camera device is increased.

The authors proposed a unified calibration method for LPM systems with different laser-line lengths that consist of a motorized linear joint and a calibration target with elaborately designed ring patterns; the authors realized the automatic parameter calibration.

In this paper the authors apply a three‐dimensional lumped parameter model (3D‐LPM) to evaluate the behaviour of an electromagnetic d.c. pump. Whit reference to the same device we compare the numerical approach with those illustrated in previous papers where we have described a bi‐dimensional model (2D‐LPM) and a quasi‐three‐dimensional lumped parameter model (3d‐LPM). The aim of this study is to note some important aspects of the full three‐dimensional (3D) analysis.

To present a Mobile Scanning System for digitizing three‐dimensional (3D) models of real‐world terrain.

A combination of sensors (video, laser range, positioning, orientation) is placed on a mobile platform, which moves past the scene to be digitized. Data fusion from the sensors is performed to construct an accurate 3D model of the target environment.

The developed system can acquire accurate models of real‐world environments in real time, at resolutions suitable for a variety of tasks.

Treating the individual subsystems of the mobile scanning system independently yields a robust system that can be easily reconfigured on the fly for a variety of scanning scenarios.

The purpose of this paper is to mainly review the state-of-the-art developments in the field of hydrodynamics of offshore pipelines, identifying the key tools for analysis of pipeline free spans, their applications, their qualifying characteristics and capabilities and limitations.

These different analytical, numerical and semi-empirical tools available for predicting such hydrodynamic loads and their effects include VIVANA, PIPESIN, VIVSIM, SIMULATOR, FATFREE, amongst others. Inherent in these models are current effects, wave effects and/ or pipe–soil interactions.

Amongst these models, the most attention was given to the new VIVANA model because this model take into account the vortex-induced effects with respect to free-spanning pipelines (which have dominant effect in the span analysis in deep water) better than other semi-empirical models (such as Shear 7). Recent improvements in VIVANA include its ability to have arbitrary variation in speed and direction of current, as well as the ability for calculation of pure IL and combined IL-CF response. Improvements in fatigue assessments at free spans, i.e. pipe–soil interaction have been achieved through the combined frequency domain and non-linear time domain analysis methodology adopted. Semi-empirical models are still the de facto currently used in the design of free-spanning pipelines. However, there is need for further research on free-span hydrodynamic coefficients and on how in-line and cross-flow vibrations interact. Again, there is still the challenge due to VIV complexity in fully understanding the fluid structure interaction problem, as there is no consolidated procedure for its analysis. It has been observed that there is large scatter between the different codes adopted in the prediction of fatigue damage, as there lacks full-scale test data devoted to determination/validation of the coefficients used in the semi-empirical models. A case study of the preliminary design of a typical 48 in. pipeline has been presented in this study to demonstrate the use of the free-span analysis tool, DNV RP F105. Excel spreadsheet has been applied in the execution of formulas.

This review paper is the first of its kind to study the state-of-the-art development in pipeline free-span analysis models and demonstrate the use of analysis tool, DNV for MAFSL calculation. Hence, information obtained from this paper would be invaluable in assisting designers both in the industry and academia.

The asymmetry of the velocity profile caused by geometric deformation, complex turbulent motion and other factors must be considered to effectively use the flowmeter on any section. This study aims to better capture the flow field information and establish a model to predict the profile velocity, we take the classical double elbow as the research object and propose to divide the flow field into three categories with certain common characteristics.

The deep learning method is used to establish the model of multipath linear velocity fitting profile average velocity. A total of 480 groups of data are taken for training and validation, with ten integer velocity flow fields from 1 m/s to 10 m/s. Finally, accuracy research with relative error as standard is carried out.

The numerical experiment yielded the following promising results: the maximum relative error is approximately 1%, and in the majority of cases, the relative error is significantly lower than 1%. These results demonstrate that it surpasses the classical optimization algorithm Equal Tab (5%) and the traditional artificial neural network (3%) in the same scenario. In contrast with the previous research on a fixed profile, we focus on all the velocity profiles of a certain length for the first time, which can expand the application scope of a multipath ultrasonic flowmeter and promote the research on flow measurement in any section.

This work proposes to divide the flow field of double elbow into three categories with certain common characteristics to better capture the flow field information and establish a model to predict the profile velocity.

This study aims to deal with development and performance analysis of high-velocity oxy-fuel (HVOF) thermally sprayed Mo₂C-based WC-CoCr (tungsten carbine cobalt chrome) (Co-10% and Cr-4%) cermet coating deposited on the pump impeller steel 316 L.

In this work, a study was carried out by modifying the conventional WC-CoCr powder with a small addition of molybdenum carbide (Mo₂C). Reinforcement was done by 1–4 wt.% addition of Mo₂C feedstocks in WC-CoCr powder by using a jar ball mill process. The design of experiment was implemented for optimization of the percentage of Mo₂C feedstock. L16 (4 × 4) orthogonal array was used to design the experiments for erosion output for the input parameters namely velocity, particle size, concentration and Mo₂C proportion.

Results show that the Mo₂C-based WC-CoCr coating provides better microhardness as compared to conventional WC-CoCr coating. The present study also reveals that the deposition of conventional WC-CoCr coating has improved the wear resistance of SS 316 L by 9.98%. However, the slurry erosion performance of conventional WC-CoCr coating was improved as 69.6% by the addition of 3% Mo₂C.

WC-CoCr coatings are universally used for protecting the equipment and machinery from abrasion, erosion and corrosion. So, the 3% Mo₂C-based WC-CoCr can be useful in power plants and various industries like mining, chemical, automobile, cementing and food processing industries.

A new HVOF coating has been developed by the addition of Mo₂C feedstock in WC-CoCr powder (Co 10% and Cr 4%) and the percentage of Mo₂C feedstock was optimized to improve the tribological behavior of WC-CoCr coating.

Additive manufacture (AM) such as selective laser melting (SLM) provides significant geometric design freedom in comparison with traditional manufacturing methods. Such freedom enables the construction of injection moulding tools with conformal cooling channels that optimize heat transfer while incorporating efficient internal lattice structures that can ground loads and provide thermal insulation. Despite the opportunities enabled by AM, there remain a number of design and processing uncertainties associated with the application of SLM to injection mould tool manufacture, in particular from H13/DIN 1.2344 steel as commonly used in injection moulds. This paper aims to address several associated uncertainties.

A number of physical and numerical experimental studies are conducted to quantify SLM-manufactured H13 material properties, part manufacturability and part characteristics.

Findings are presented which quantify the effect of SLM processing parameters on the density of H13 steel components; the manufacturability of standard and self-supporting conformal cooling channels, as well as structural lattices in H13; the surface roughness of SLM-manufactured cooling channels; the effect of cooling channel layout on the associated stress concentration factor and cooling uniformity; and the structural and thermal insulating properties of a number of structural lattices.

The contributions of this work with regards to SLM manufacture of H13 of injection mould tooling can be applied in the design of conformal cooling channels and lattice structures for increased thermal performance.

The purpose of this paper is to review the sensor technology innovations featured at the International Manufacturing Technology Show (IMTS).

In‐depth interviews with exhibitors of sensor products were undertaken.

Sensor technology continues to grow rapidly to keep up with manufacturing trends such as the need for better product quality, nano‐technology, automated testing, and an ever growing interest in 100 percent in process production testing.

Manufacturers are finding answers to many quality assessment needs with the rapid advances being made by sensor device and inspection system suppliers to offer innovative ways to better inspect components.

Manufacturers are finding answers to many quality assessment needs with the rapid advances being made by sensor device and inspection system suppliers to offer innovative ways to better inspect components.

This paper aims to introduce a new nesting scheme to better describe and solve the single-layer-part packing problem in additive manufacturing (AM).

Parallel nesting scheme using two-dimensional (2D) changeable projection profiles is developed. At first, a feature-based orientation optimization method is used to identify a set of practical alternative build orientations for each part to ensure the part quality. Then, 2D polygons are used to represent each part’s projection profiles under its alternative build orientations. Finally, a parallel layout searching algorithm is developed to identify the optimal part layout by using 2D changeable projection profiles.

The proposed nesting scheme can both guarantee the production quality for each part and search the optimal part layout with larger probability but less computational time.

With the use of changeable 2D projection profiles, this method conducts 2D computation to solve the single-layer-part packing problem with five degrees of freedom, which saves much computation cost and, at the same time, guarantees the production quality of each part. By adding specific nesting objectives or constraints and heuristic searching knowledge to the proposed nesting scheme, practical nesting software can be developed to meet the specific nesting or packing requirements for industrial AM machines.

Recognition of machining features is an essential step in the development of efficient‐automated process plans from solid modeling data. This process represents the effective interpretation of the geometric data in a computer‐aided design (CAD) model to create semantically rich manufacture‐oriented features such as holes, slots, pockets, and others that may be exploited in downstream computer‐aided manufacturing/computer‐aided process planning applications. Most successful approaches towards feature recognition have been based on hint‐based procedures operating on a 3D B‐Rep model. The purpose of this paper is to propose an approach by which features are identified in a solid model that is built mainly using sweep solid modeling operations.

Part geometric model is queried for both 2D and 3D geometric elements. Feature hints are generated by an analysis of sweep operations and their 2D sketches, which are defined prior to building the solid model. These hints are then analyzed and validated by applying a two‐phase approach: 2D validation in the sketch geometry; and 3D validation in the final constructive solid geometry tree of the solid model. Valid hints are the basis for the creation of a machining feature model that can be input to a process planning module. In addition, interaction information for machining features is extracted from both 2D hints and their 3D validation. Feature interaction information is obtained by analysis of face/edge neighborhood and their geometric relations in both 2D and 3D spaces.

This approach provides a benefit of performing the majority of geometric analysis in 2D space which is much simpler and computationally more efficient than corresponding analyses in 3D space. Only minimal portion of the analysis is computed on 3D solid models. The approach is implemented in the Java‐based prototype system and is demonstrated and tested on several real‐world examples.

The initial prototype implementation is limited to prismatic parts and linear sweep. Only hole and slot feature can be recognized due to the fact that pocket recognition appears to be trivial.

Motivation for this approach is in the fact that sweep operations from 2D sketches are very commonly used in the mechanical design process, so the approach may be applicable in practical applications of CAD.

This novel approach provides value to product designers and manufacturing planners since linear (extrusion) and circular (rotation) sweeps are very popular design engineer tools.