Determination of True Dimensional Quality and Build Errors Using Coordinate Measurement Data

1999 ◽  
Vol 121 (4) ◽  
pp. 749-755 ◽  
Author(s):  
R. J. Gu ◽  
G. C. Barber
Keyword(s):  
Measurement Data ◽  
Coordinate Measuring Machine ◽  
Coordinate Frame ◽  
Numerical Examples ◽  
Coordinate Measurement ◽  
Acceptable Quality ◽  
Measuring Machine ◽  
Material Points

For manufacturing personnel there exist two major tasks: determination of the quality of the build, and locating build errors if the quality is inferior. To serve this purpose a coordinate measuring machine is employed to determine the actual locations of designated material points. Depending on the measuring coordinate frame chosen, the initial raw data, unfortunately, do not impartially represent the true deviations of all the measurement points. This paper shows a technique to overcome this inevitable drawback embedded in the CMMs and determine if the build has acceptable quality under specified tolerances. Also presented in this paper is a method to quantify the quality of the measurement points for easy identification of build errors. Numerical examples are given to demonstrate the feasibility of the technique.

Evaluation of Actual Geometric Tolerances Using Coordinate Measuring Machine Data

1989 ◽  
Author(s):  
W. H. ElMaraghy ◽  
Z. Wu ◽  
H. A. ElMaraghy
Keyword(s):  
Three Dimensional ◽  
Measurement Data ◽  
Simulated Data ◽  
Coordinate Measuring Machine ◽  
Optimization Techniques ◽  
Test Cases ◽  
Tolerance Zone ◽  
Geometric Tolerances ◽  
Measuring Machine

Abstract This paper focuses on the development of a procedure and algorithms for the systematic comparison of geometric variations of measured features with their specified geometric tolerances. To automate the inspection of mechanical parts, it is necessary to analyze the measurement data captured by coordinate measuring machines (CMM) in order to detect out-of-tolerance conditions. A procedure for determining the geometric tolerances from the measured three dimensional coordinates on the surface of a cylindrical feature is presented. This procedure follows the definitions of the geometric tolerances used in the current Standards, and is capable of determining the value of each geometric tolerance from the composite 3-D data. The developed algorithms adopt the minimum tolerance zone criterion. Nonlinear numerical optimization techniques are used to fit the data to the minimum tolerance zone. Two test cases are given in the paper which demonstrate the successful determination of geometric tolerances from given simulated data.

Inspecting Profile Errors of Conjugate Disk Cams With Coordinate Measurement

2008 ◽  
Vol 130 (1) ◽  
Author(s):  
Wen-Tung Chang ◽  
Long-Iong Wu ◽  
Kuang-Hua Fuh ◽  
Chen-Chou Lin
Keyword(s):  
Interpolation Method ◽  
Measurement Data ◽  
Coordinate Measuring Machine ◽  
Coordinate Measurement ◽  
Numerical Interpolation ◽  
Radial Dimension ◽  
Cam Profile ◽  
Measuring Machine ◽  
Profile Errors ◽  
Coordinate Data

To inspect cam profile errors, a coordinate measuring machine (CMM) is frequently employed. The coordinate data of discrete points at the cam surface are measured by a CMM in order to further evaluate the actual cam profile with complicated interpolation algorithms, and then the cam contour approximated by these algorithms may be compared with the theoretical one. In this paper, a direct and simple analytical method, instead of a numerical interpolation algorithm, is proposed for inspecting the profile deviations of conjugate disk cams with coordinate measurement data. The method is based on the derived correlation between the radial-dimension errors and the normal-direction errors of conjugate cam profiles. To verify the proposed method, an experiment of inspecting a pair of conjugate disk cam profiles was conducted. The experimental results obtained from the proposed method were compared with those obtained by using the Hermite interpolation method. It shows that this method is accurate and more efficient for inspecting the profile errors of conjugate disk cams.

scholarly journals Study of the Influence of Technological Parameters on Generating Flat Part with Cylindrical Features in 3D Printing with Resin Cured by Optical Processing

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1941
Author(s):  
Aurel Tulcan ◽  
Mircea Dorin Vasilescu ◽  
Liliana Tulcan
Keyword(s):  
3D Printing ◽  
Flat Surface ◽  
Coordinate Measuring Machine ◽  
3D Printer ◽  
Light Control ◽  
Technological Parameters ◽  
Optical Processing ◽  
Measuring Machine ◽  
The Impact

The objective of this paper is to determine how the supporting structure in the DLP 3D printing process has influences on the characteristics of the flat and cylindrical surfaces. The part is printed by using the Light Control Digital (LCD) 3D printer technology. A Coordinate Measuring Machine (CMM) with contact probes is used for measuring the physical characteristics of the printed part. Two types of experiment were chosen by the authors to be made. The first part takes into consideration the influence of the density of the generated supports, at the bottom of the printed body on the characteristics of the flat surface. In parallel, it is studying the impact of support density on the dimension and quality of the surface. In the second part of the experiment, the influence of the printed supports dimension on the flatness, straightness and roundness of the printed elements were examined. It can be observed that both the numerical and dimensional optimum zones of the support structure for a prismatic element could be determined, according to two experiments carried out and the processing of the resulting data. Based on standardized data of flatness, straightness and roundness, it is possible to put in accord the values determined by measurement within the limits of standardized values.

scholarly journals A frame for a computer aided inspection planning system

2015 ◽  
Vol 4 (1) ◽  
pp. 125 ◽  
Author(s):  
Wilma Polini ◽  
Giovanni Moroni
Keyword(s):  
Measurement Techniques ◽  
Coordinate Measuring Machine ◽  
Planning System ◽  
Inspection Planning ◽  
Coordinate Measurement ◽  
Measurement Results ◽  
Measuring Machine ◽  
Set Up ◽  
Almost All ◽  
Computer Aided Inspection

Coordinate Measuring Machine (CMM) inspection planning is an activity performed by well-trained operators, but different measurement techniques, using the same data analysis algorithms yield in different measurement results. This is a well-recognized source of uncertainty in coordinate measurement. A CMM, provided with an automatic inspection planning (CAIP) system, permits to implement more accurate and efficient operating procedures and to fit higher quality assurance standards and tighter production timings.In this paper we present a frame of a CAIP system, able to deal with almost all the decisional stages of CMM inspection. Moreover, original approaches have been developed and presented in inspection feature selection, part set-up, probe configuration, and path planning.

Methodology for evaluate the form deviations for formula one nose car

2014 ◽  
Vol 4 (2) ◽  
Author(s):  
Paul Bere ◽  
Calin Neamtu
Keyword(s):  
Composite Material ◽  
Laser Scanning ◽  
Coordinate Measuring Machine ◽  
3D Scanning ◽  
Cad Model ◽  
3D Laser Scanning ◽  
Formula One ◽  
Dimensional Deviation ◽  
Measuring Machine

AbstractThe paper presents a measuring strategy for a Formula One car using a Coordinate Measuring Machine (CMM) and a 3D laser scanning devices. The measurement procedures outlined the dimensional deviation of the CAD model and prototype made of composite material. The authors present two methods for the determination of symmetry for components of a Formula One car based on measuring and 3D scanning.

scholarly journals The Hybrid Coordinate Measurement System as a Response to Industrial Requirements

2010 ◽  
Vol 17 (1) ◽  
pp. 109-117 ◽  
Author(s):  
Jerzy Sładek ◽  
Robert Sitnik ◽  
Magdalena Kupiec ◽  
Paweł Błaszczyk
Keyword(s):  
Hybrid System ◽  
Measurement System ◽  
Coordinate Measurement ◽  
Manufactured Products ◽  
Segmentation Algorithms ◽  
High Measurement ◽  
Accuracy Determination ◽  
Plate Measurement

The Hybrid Coordinate Measurement System as a Response to Industrial RequirementsThe tendencies of modern industry are to increase the quality of manufactured products, simultaneously decreasing production time and cost. The hybrid system combines advantages of the high accuracy of contact CMM and the high measurement speed of non-contact structured light optical techniques. The article describes elements of a developed system together with the steps of the measurement process of the hybrid system, with emphasis on segmentation algorithms. Additionally, accuracy determination of such a system realized with the help of a specially designed ball-plate measurement standard is presented.

scholarly journals On the Numerical Determination of Optimal Textures of Aluminium

1994 ◽  
Vol 22 (3) ◽  
pp. 177-186 ◽  
Author(s):  
P. Burgholzer ◽  
O. Scherzer
Keyword(s):  
Mathematical Model ◽  
Nonlinear Optimization ◽  
Deep Drawing ◽  
Optimization Problem ◽  
Numerical Determination ◽  
Nonlinear Optimization Problem ◽  
Numerical Examples ◽  
Mathematical Algorithm

In this paper a mathematical algorithm is studied to improve the deep-drawing quality of an aluminium sheet. The deep-drawing quality is usually expressed in terms of the normal anisotropie. In our mathematical model we use Taylor theory and ideal orientations to reformulate this problem as a nonlinear optimization problem for the normal anisotropie. Some numerical examples are presented.

scholarly journals Geometric analysis of injection-molded polymer gears (Rapid communication)

Polimery ◽  
2021 ◽  
Vol 66 (1) ◽  
pp. 56-62
Author(s):  
Jadwiga Pisula
Keyword(s):  
Geometric Analysis ◽  
Coordinate Measuring Machine ◽  
Accuracy Class ◽  
Coordinate Measurement ◽  
Gear Teeth ◽  
Single Tooth ◽  
Measurement Results ◽  
Measuring Machine ◽  
Injection Molded

Properties of polymer gears were tested using coordinate measurement methods. This study is a follow-up to research on geometric accuracy of gears manufactured by injection molding. Spur gears were measured on a coordinate measuring machine running the GINA software by Klingelnberg. Measurement results were output in the form of measurement sheets which included values required in the DIN 3962 standard. The article also analyses the topography of test gear teeth. The topography was presented for a single tooth of the gear and determined on the basis of the measurements of 9 profiles distributed evenly over a specific profile assessment interval (interval Lα defined in the standard) and 7 tooth traces located within a relevant tooth trace assessment interval (interval Lβ defined in the standard). All gears tested in this study were placed outside accuracy class 12.

Determining the surface form of polystyrene through the coordinate measurement machine

2003 ◽  
Vol 217 (7) ◽  
pp. 839-844 ◽  
Author(s):  
D Aitchison ◽  
R Sulaiman
Keyword(s):  
Food Packaging ◽  
Coordinate Measuring Machine ◽  
Medical Application ◽  
Surface Form ◽  
Daily Lives ◽  
Coordinate Measurement ◽  
Different Temperatures ◽  
Measuring Machine ◽  
Different Shapes ◽  
Drilling Rigs

The market for foam materials has been growing rapidly throughout the world as they have a variety of uses. Some examples are in the automotives industries, food packaging industries, medical application, sports gears, home insulations and floatation in offshore drilling rigs, buoys and small boats. Since the uses of foam affects greatly the daily lives of humans, the need to have foams in different shapes requires speed in cutting and manufacture. This can only be done through computer aided cutting machines or automated cutting of foams. However, the speed of cutting will affect the surface finish of the cut. Therefore, it is necessary to determine the surface form of the polystyrene to achieve quality results. This is an on-going research to produce a rapid-prototyping machine that cuts foam models. The first phase of this research is to determine the surface form of polystyrene through the use of a coordinate measuring machine (CMM), after being cut with different types of wires, at different temperatures and cutting feedrates.

Slicing: A Procedure for Tolerance Evaluation of Manufactured Parts Using CMM Measurement Data

1995 ◽  
Author(s):  
Yu Wang ◽  
Shilendra Gupta ◽  
Srinavas Rao
Keyword(s):  
Computational Complexity ◽  
Measurement Data ◽  
Coordinate Measuring Machine ◽  
Significant Loss ◽  
Processing Procedure ◽  
Machined Parts ◽  
Measuring Machine ◽  
Part Model

Abstract This paper presents a sampling and processing procedure for tolerance evaluation of machined parts. In this method, deviations of the measured points from their ideal feature surface are evaluated in the plane where the data is measured by a Coordinate Measuring Machine (CMM). This procedure is called slicing. It is shown that the use of the structure inherent in measurement data has a potential in reducing computational complexity for evaluation of certain types of form tolerances without significant loss of accuracy. An application of the proposed method to the development of manufactured part model for automotive spaceframe structures is also discussed.

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