61 research outputs found
Mathematical models for estimating the degree of influence of major factors on performance and accuracy of coordinate measuring machines
No full textIncreased productivity of Coordinate Measuring Machines, while providing given level of accuracy, is complex and actual problem of robotics and metrology. Therefore, this article provides a set of mathematical models that allow for prediction of values for performance and accuracy of advanced Coordinate Measuring Machines based on system dynamics method. The analysis of scientific literature and statistical data of exploitation CMMs Global Performance (DEA, Italy), CMM-750 (Lapik, Russia), FARO Arm 9 (FARO Technologies, USA) has identified 25 major factors of the process control and their mutual impact. Of the 16 basic factors are internal system parameters, 6 input actions and 3 external factors. As a result of the system analysis of the research object identifies the main characteristics of coordinate measuring machines that affect performance and measurement accuracy. We have done a general graph of causal relationships between modeled characteristics, on the basis of which is made up and numerically solved a system of nonlinear differential equations. In developing this system of equations is used in statistical data describing the cause-effect relationship between the internal model parameters and environmental factors. These solutions make it possible to practically interpret developed models and methods of system dynamics used in solving the problem
Mathematical models for estimating the degree of influence of major factors on performance and accuracy of coordinate measuring machines
Get PDFIncreased productivity of Coordinate Measuring Machines, while providing given level of accuracy, is complex and actual problem of robotics and metrology. Therefore, this article provides a set of mathematical models that allow for prediction of values for performance and accuracy of advanced Coordinate Measuring Machines based on system dynamics method. The analysis of scientific literature and statistical data of exploitation CMMs Global Performance (DEA, Italy), CMM-750 (Lapik, Russia), FARO Arm 9 (FARO Technologies, USA) has identified 25 major factors of the process control and their mutual impact. Of the 16 basic factors are internal system parameters, 6 input actions and 3 external factors. As a result of the system analysis of the research object identifies the main characteristics of coordinate measuring machines that affect performance and measurement accuracy. We have done a general graph of causal relationships between modeled characteristics, on the basis of which is made up and numerically solved a system of nonlinear differential equations. In developing this system of equations is used in statistical data describing the cause-effect relationship between the internal model parameters and environmental factors. These solutions make it possible to practically interpret developed models and methods of system dynamics used in solving the problem
Recent results from GRAAL
No full textA polarised and tagged (gamma) over bar ray beam is produced at GRAAL by the Compton scattering of laser light on the high energy electron of the ESRF storage ring. We present results on the beam polarisation asymmetries and cross sections in the photoproduction of mesons on hydrogen and deuterium target in the energy region 500-1500 MeV. These very precise results cover the angular range 30 degrees-150 degrees, providing stringent constraints to theoretical models
Compton scattering at GRAAL
No full textAt the GRAAL facility, a polarised and tagged ray beam is produced in the energy range from 500 MeV up to 1500 MeV. Preliminary results of beam polarization asymmetries for Compton scattering on the proton are presented. These very precise measurements cover the angular range 30°-150°, providing stringent constraints to theoretical models
Meson photoproduction on the proton at GRAAL
No full textThe GRAAL (Grenoble Anneau Accelerateur Laser) facility provides a polarized and tagged photon beam (from 500 to 1500 MeV) obtained by Compton scattering of laser light on the electron beam of ESRF (European Synchrotron Radiation Facility) in Grenoble. Mesons photoproduction off the nucleon allows to investigate the excited states of the nucleon. The p(gamma,etap) channel has been analysed and the cross-sections are given up to 1100 MeV
A large acceptance lead-scintillator time-of-flight wall for neutral and charged particles
No full textA large acceptance lead-scintillator time-of-flight (TOF) wall has been developed to detect photons, neutrons, and charged particles produced in meson-photoproduction experiments on the proton and on the neutron. A TOF resolution of 600 ps and a position resolution of 11 x 18 cm(2) (full-width at half-maximum) have been achieved. The wall has been successfully used in eta and pi(+) photoproduction experiments as a photon and a neutron detector. This paper reports its design, calibration and performance. (C) 2002 Elsevier Science B.V. All rights reserved
Meson photoproduction on the neutron at GRAAL
No full textUsing a Deuterium target, the GRAAL experiment has collected meson photoproduction data. The data have been analysed in the quasi free regime. The results of the quasi free process on the proton reproduce quite well the results previously obtained with a Hydrogen target. The preliminary results on the quasi free neutron for pi(0) and eta photoproduction are presented and discussed
Λ(1405) photoproduction at the BGO-OD experiment
Get PDFSince the discovery of the Λ(1405), it remains poorly described by conventional constituent quark models, and it is a candidate for having an “exotic” meson-baryon or “penta-quark” structure, similar to states recently reported in the hidden charm sector.
The Λ(1405) can be produced in the reaction γp K+Λ(1405). The pure I=0 decay mode into Σ0π0 is prohibited for the mass-overlapping Σ(1385). Combining a large aperture forward magnetic spectrometer and a central BGO crystal calorimeter, the BGO-OD experiment is ideally suited to measure this decay with the K+ in the forward direction. Preliminary results are presented.
*Supported by DFG (PN 388979758, 405882627
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