Towards a New Concept of In-Line Crankshaft Balancing by Contact Less Measurement: Process for Selecting the Best Digitizing System

2012 ◽  
Author(s):  
Alexandre Zuquete-Guarato ◽  
Charyar Mehdi-Souzani ◽  
Yann Quinsat ◽  
Claire Lartigue ◽  
Leila Sabri
Keyword(s):  
Quality Indicators ◽  
High Precision ◽  
Measurement Process ◽  
Scanning System ◽  
Specific Procedure ◽  
Measuring Systems ◽  
Accessibility Issues ◽  
Definition Of

Controlling the part’s balance of crankshafts are important issues for automotive manufacturers. Unbalance measurement is usually carried out using high-precision mechanical machines. The main objective of the present work is to replace mechanical measuring systems by a non-contact digitizing system, which permits the acquisition of the crankshaft surface. As the geometry to be measured presents a large variety of shapes and textures with accessibility issues, the definition of the best-suited scanning system related to geometrical and industrial constraints is a major issue. In this direction, the paper deals with the definition of a protocol based on quality indicators associated to the collected data to compare various digitizing systems. Those quality indicators are assessed thanks to simple artifacts measurement according to a specific procedure. The comparison protocol is applied to evaluate three triangulation based digitizing systems: Results allow us to identify well-adapted digitizing systems in relation to crankshaft balancing requirements.

scholarly journals A High-Precision Registration Technology Based on Bundle Adjustment in Structured Light Scanning System

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Jianying Yuan ◽  
Qiong Wang ◽  
Xiaoliang Jiang ◽  
Bailin Li
Keyword(s):  
High Precision ◽  
Large Scale ◽  
Structured Light ◽  
Bundle Adjustment ◽  
Scanning System ◽  
Control Points ◽  
Registration Method ◽  
Global Control ◽  
3D Data ◽  
Structured Light Scanning

The multiview 3D data registration precision will decrease with the increasing number of registrations when measuring a large scale object using structured light scanning. In this paper, we propose a high-precision registration method based on multiple view geometry theory in order to solve this problem. First, a multiview network is constructed during the scanning process. The bundle adjustment method from digital close range photogrammetry is used to optimize the multiview network to obtain high-precision global control points. After that, the 3D data under each local coordinate of each scan are registered with the global control points. The method overcomes the error accumulation in the traditional registration process and reduces the time consumption of the following 3D data global optimization. The multiview 3D scan registration precision and efficiency are increased. Experiments verify the effectiveness of the proposed algorithm.

scholarly journals Solar barycentric dynamics from a new solar-planetary ephemeris

2018 ◽  
Vol 615 ◽  
pp. A153 ◽  
Author(s):  
Rodolfo G. Cionco ◽  
Dmitry A. Pavlov
Keyword(s):  
High Precision ◽  
Orbital Motion ◽  
Giant Planets ◽  
Reference Plane ◽  
The Sun ◽  
The Future ◽  
Dynamical Parameters ◽  
Definition Of ◽  
Invariable Plane ◽  
Planetary Theories

Aims. The barycentric dynamics of the Sun has increasingly been attracting the attention of researchers from several fields, due to the idea that interactions between the Sun’s orbital motion and solar internal functioning could be possible. Existing high-precision ephemerides that have been used for that purpose do not include the effects of trans-Neptunian bodies, which cause a significant offset in the definition of the solar system’s barycentre. In addition, the majority of the dynamical parameters of the solar barycentric orbit are not routinely calculated according to these ephemerides or are not publicly available. Methods. We developed a special version of the IAA RAS lunar–solar–planetary ephemerides, EPM2017H, to cover the whole Holocene and 1 kyr into the future. We studied the basic and derived (e.g., orbital torque) barycentric dynamical quantities of the Sun for that time span. A harmonic analysis (which involves an application of VSOP2013 and TOP2013 planetary theories) was performed on these parameters to obtain a physics-based interpretation of the main periodicities present in the solar barycentric movement. Results. We present a high-precision solar barycentric orbit and derived dynamical parameters (using the solar system’s invariable plane as the reference plane), widely accessible for the whole Holocene and 1 kyr in the future. Several particularities and barycentric phenomena are presented and explained on dynamical bases. A comparison with the Jet Propulsion Laboratory DE431 ephemeris, whose main differences arise from the modelling of trans-Neptunian bodies, shows significant discrepancies in several parameters (i.e., not only limited to angular elements) related to the solar barycentric dynamics. In addition, we identify the main periodicities of the Sun’s barycentric movement and the main giant planets perturbations related to them.

Methodology for managing quality indicators of hardware products with elements of robust design

2020 ◽  
pp. 38-43
Author(s):  
K. G. Pivovarova ◽  
◽  
A. G. Korchunov ◽  
Keyword(s):  
Product Quality ◽  
Quality Indicators ◽  
Robust Design ◽  
Control Method ◽  
Efficient Production ◽  
Related Quality ◽  
Definition Of ◽  
Noise Factors ◽  
The Impact

Production of metalware is characterized with a great variety of shapes and sizes, originality of each product and a multiple-stage process. Various techniques used to process steel sections (such as cold and hot forming, machining, heat treatment, etc.) make it significantly more difficult to tackle product quality problems. Modern product quality management methodologies are based on a wide use of economical, organizational, technical and other methods. This paper describes a production-related quality control method involving certain elements of robust design. This method is based on the definition of noise factors and control parameters, as well as the conduction of noise and principal experiments. The noise experiment will help estimate the impact of disturbing factors (environmental or industrial) on product quality indicators, whereas the principal experiment will help identify the optimum production mode that can deliver the best quality and, at the same time, minimize the production losses. Robust design techniques can be effectively utilized to control the quality of metalware when developing new and optimizing the existing processes. The paper gives an example of how the quality of S10S steel bars can be controlled through the application of efficient production modes enabling to minimize quality-related costs.

ACCURACY OF MEASURING SYSTEMS BASED ON LASER MODULES

2020 ◽  
pp. 44-53 ◽  
Author(s):  
V. E. Makhov ◽  
A. V. Emelyanov ◽  
A. I. Potapov ◽  
V. M. Petrushenko
Keyword(s):  
High Precision ◽  
Experimental Studies ◽  
Adaptive Algorithms ◽  
Measuring Systems ◽  
Precision Measuring ◽  
Relative Coordinates ◽  
Laser Module ◽  
Absolute Coordinates ◽  
Preliminary Selection

Measuring systems using the design of laser module beams on the surface of the object under study are considered. A technique is proposed for experimental studies of the brightness structure of the study of laser modules for their subsequent testing. Adaptive algorithms for determining the type of module and distance have been developed for determining the coordinates of light marks on the surface of controlled products, ensuring the accuracy and reliability of the measurement. The need for high-precision measuring systems to carry out their preliminary selection and calibration of laser modules according to the proposed method, taking into account the range of design of light marks, is shown. It is shown in the work that the accuracy of determining the relative coordinates in the trajectory of the light marks of laser modules at a distance of 5 m for plain surfaces of the observed objects can be several times higher (0,2…0,3 mm) of the accuracy of determining their absolute coordinates (»1 mm).

Impact of high precision gravimetry in the context of a future new SI

2014 ◽  
Vol 30 ◽  
pp. 1460270
Author(s):  
Henri Baumann ◽  
Ali L. Eichenberger
Keyword(s):  
High Precision ◽  
Laser Interferometer ◽  
Mass Unit ◽  
Research Areas ◽  
Gravity Measurements ◽  
Definition Of ◽  
New Research ◽  
New Si ◽  
The Doors

In the early eighties, the development of ballistic absolute gravimeters based on laser interferometer opened the doors to new research areas in various scientific domains such as geodesy, geophysics or metrology. After a brief overview of the most used technique for gravity measurements, the implication of gravity in the context of an improved SI, especially for a new definition of the mass unit kg, will be presented.

scholarly journals High precision scanning system and test technology of remote sensor

2016 ◽  
Vol 77 ◽  
pp. 05002
Author(s):  
Xiaole Yang ◽  
Jianbing Kang ◽  
Dongjie Wang ◽  
Xin Zhao
Keyword(s):  
High Precision ◽  
Scanning System ◽  
Remote Sensor ◽  
Test Technology
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