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The estimation of vessels' centerlines is a critical step in assessing the geometry of the vessel, the topological representation of the vessel tree, and vascular network visualization. In this research, we present a novel method for obtaining geometric parameters from peripheral arteries in 3D medical binary volumes. Our approach focuses on centerline extraction, which yields smooth and robust results. The procedure starts with a segmented 3D binary volume, from which a distance map is generated using the Euclidean distance transform. Subsequently, a skeleton is extracted, and seed points and endpoints are identified. A search methodology is used to derive the best path on the skeletonized 3D binary array while tracking from the goal points to the seed point. We use the distance transform to calculate the distance between voxels and the nearest vessel surface, while also addressing bifurcations when vessels divide into multiple branches. The proposed method was evaluated on 22 real cases and 10 synthetically generated vessels. We compared our method to different state-of-the-art approaches and demonstrated its better performance. The proposed method achieved an average error of 1.382 mm with real patient data and 0.571 mm with synthetic data, both of which are lower than the errors obtained by other state-of-the-art methodologies. This extraction of the centerline facilitates the estimation of multiple geometric parameters of vessels, including radius, curvature, and length. [ABSTRACT FROM AUTHOR]

A support control automation system employing force sensors to a large-size crankshaft main journals’ flexible support-system was studied. The current system was intended to evaluate the geometric condition of crankshafts in internal combustion diesel engines. The support reaction forces were changed to minimize the crankshaft elastic deflection as a function of the crank angle. The aim of this research was to verify the hypothesis that the mentioned change can be expressed by a monoharmonic model regardless of a crankshaft structure. The authors’ investigations have confirmed this hypothesis. It was also shown that an algorithmic approach improved the mathematical model mapping with the reaction forces due to faster and more accurate calculations of a phase shift angle. The verification of the model for crankshafts with different structural designs made it possible to assess how well the model fits the coefficients of determination that were calculated with the finite element analysis (FEA). For the crankshafts analyzed, the coefficients of determination R2 were greater than 0.9997, while the maximum relative percentage errors δmax were up to 1.0228%. These values can be considered highly satisfactory for the assessment of the conducted study.

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Safety is one of the key aspects related to crane-based material transport. In order to ensure safe crane operation and material transport, it is necessary to meet certain geometrical conditions. The authors addressed the geometrical conditions of a crane bridge, a substantial crane component. The paper presents the method to compute displacement components of points on the top of a bridge crane relative to their design position. Theoretical considerations presented in the paper have been verified on simulated data. Keeping in mind the proper operation of a crane bridge, the authors proposed in the analyses the use of geometrical relations (perpendicular and parallel character) between end carriages and girders, not previously included in the available literature. The obtained results show that the presented method may be successfully applied to check the geometry of a crane bridge.

This article describes an innovative method for eliminating deformation in large crankshafts during measurement of their geometric condition. The currently available techniques for measuring crankshaft geometry are introduced and classified according to their applicability and the method of measurement. The drawbacks of the methods have been identified and a solution to these problems has been proposed. The influence of the rigid support of a shaft on its deformation, and thus on the reduction in the accuracy of crankshaft geometry measurements, has also been investigated. The concept and main versions of the proposed measuring system with active compensation for shaft deflection, by means of actuators cooperating with force transducers monitoring the deflection of individual crank journals of a crankshaft being measured, have been presented and the flexible support control system has also been described. The problems relating to the operation of the control system have been furnished along with a way to solve them, including the issue of noise reduction in the signal from the force transducer and the influence of the controller parameters on the operation of the flexible support. The computer system that controls the flexible supports has been briefly characterized, and the performance of the prototype system and the model reference system has been compared. The results have shown that the system is able to effectively eliminate the deflection and elastic deformation of the crankshaft under the influence of its own weight.

In the paper the application of ToF laser scanner in measurements of geometrical parameters of a boiler drum used in a power plant is presented. These parameters are required during renovation works, for verification of correctness of annealing process and optimization of the process of mounting a mechanical steam–water separation. The currently used separations are tightly placed in a boiler drum, so a welding process is not required anymore. This approach saves the time of renovation works, but the geometry of a separation has to be precisely matched against the geometry of the drum to ensure the tightness of connection and, in consequence, to ensure stability of steam parameters (pressure and temperature). Renovation works may include heating processes, after which geometry should also be carefully verified as improperly performed can lead to buckling of a boiler drum. In the presented approach ToF scanner provides cloud of points, which has been subjected to a set of post-processing operations including stitching, cylinder fitting, projection 3D data onto 2D map, 2D data interpolation and filtering. As the result, the required dimensions and tolerances are obtained and are ready for further implementation. [ABSTRACT FROM AUTHOR]

A support control automation system employing force sensors to a large-size crankshaft main journals' flexible support-system was studied. The current system was intended to evaluate the geometric condition of crankshafts in internal combustion diesel engines. The support reaction forces were changed to minimize the crankshaft elastic deflection as a function of the crank angle. The aim of this research was to verify the hypothesis that the mentioned change can be expressed by a monoharmonic model regardless of a crankshaft structure. The authors' investigations have confirmed this hypothesis. It was also shown that an algorithmic approach improved the mathematical model mapping with the reaction forces due to faster and more accurate calculations of a phase shift angle. The verification of the model for crankshafts with different structural designs made it possible to assess how well the model fits the coefficients of determination that were calculated with the finite element analysis (FEA). For the crankshafts analyzed, the coefficients of determination R2 were greater than 0.9997, while the maximum relative percentage errors δmax were up to 1.0228%. These values can be considered highly satisfactory for the assessment of the conducted study. [ABSTRACT FROM AUTHOR]

• We proposed an improvement for the crank shaft geometry measurement system. • We proposed models to support large crankshafts geometry measurements. • We used these models to map the reaction forces in the flexible crankshaft. • We calculated relative errors and R2s of the models for an example crankshaft. • We provided proof that the monoharmonic model fits basic data well. We have previously described a novel crankshaft support system that can be used when measuring and testing crankshafts. Here, we extend our studies on this system using mathematical models (basic polyharmonic, spline-based polyharmonic, and monoharmonic functions) to identify the optimal conditions for supporting geometric measurements of large crankshafts. The obtained results improved the accuracy of this system and provided alternative solutions by minimizing shaft deflection during measurements. It was proposed and confirmed that variable reaction forces in flexible crankshaft supports can be mapped using a monoharmonic model with a good fit to the source data. At various selected crankshaft positions, finite element analysis software was used to determine the reaction forces, for which three different mathematical models were tested. The usefulness of each individual model was discussed in terms of the complexity and accuracy of mapping the source values. [ABSTRACT FROM AUTHOR]

Safety is one of the key aspects related to crane-based material transport. In order to ensure safe crane operation and material transport, it is necessary to meet certain geometrical conditions. The authors addressed the geometrical conditions of a crane bridge, a substantial crane component. The paper presents the method to compute displacement components of points on the top of a bridge crane relative to their design position. Theoretical considerations presented in the paper have been verified on simulated data. Keeping in mind the proper operation of a crane bridge, the authors proposed in the analyses the use of geometrical relations (perpendicular and parallel character) between end carriages and girders, not previously included in the available literature. The obtained results show that the presented method may be successfully applied to check the geometry of a crane bridge. [ABSTRACT FROM AUTHOR]

This article describes an innovative method for eliminating deformation in large crankshafts during measurement of their geometric condition. The currently available techniques for measuring crankshaft geometry are introduced and classified according to their applicability and the method of measurement. The drawbacks of the methods have been identified and a solution to these problems has been proposed. The influence of the rigid support of a shaft on its deformation, and thus on the reduction in the accuracy of crankshaft geometry measurements, has also been investigated. The concept and main versions of the proposed measuring system with active compensation for shaft deflection, by means of actuators cooperating with force transducers monitoring the deflection of individual crank journals of a crankshaft being measured, have been presented and the flexible support control system has also been described. The problems relating to the operation of the control system have been furnished along with a way to solve them, including the issue of noise reduction in the signal from the force transducer and the influence of the controller parameters on the operation of the flexible support. The computer system that controls the flexible supports has been briefly characterized, and the performance of the prototype system and the model reference system has been compared. The results have shown that the system is able to effectively eliminate the deflection and elastic deformation of the crankshaft under the influence of its own weight. [ABSTRACT FROM AUTHOR]