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Coordinate Measuring Machines and Systems DownloadPDF MB Read online. Since John Bosch edited and published the first version. Why coordinate measuring machine is an exellent investment Money talks; SYSTEMS IS THE BACKBONE TO. PROGRAMME CMM. The article presents the conception of coordinate measurement. The characteristic of two systems (Coordinate Measuring Machine – CMM and.

Coordinate Measuring Machines And Systems Pdf

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Coordinate Measuring Machines (CMMs) are extremely powerful metrological instruments: High unit cost—Because reworking or scrapping is costly, CMM systems significantly yazik.info References p //. Probe Systems for Coordinate Measuring Machines. Principle of an Electro-Mechanical Switching Probe. Principle of a Measuring Probe with . Results 1 - 20 of [READ ONLINE] Coordinate Measuring Machines and Systems, Second Edition by Robert J. Hocken, Paulo H. Pereira. Book file PDF easily.

Since John Bosch edited and published the first version of this book in , the world of manufacturing and coordinate measuring machines CMMs and coordinate measuring systems CMSs has changed considerably. However, the basic physics of the machines has not changed in essence but have become more deeply understood.

Completely revised and updated to reflect the change that have taken place in the last sixteen years, Coordinate Measuring Machines and Systems, Second Edition covers the evolution of measurements and development of standards, the use of CMMs, probing systems, algorithms and filters, performance and financial evaluations, and accuracy.

Explores the rising expectations of the user for operator interfaces, ease of use, algorithms, speed, communications, and computational capabilities Details the expansion of machines such as the non-Cartesian CMM in market share and their increase in accuracy and utility Discusses changes in probing systems, and the number of points they can deliver to ever more sophisticated software Examines the pressures created by new applications to improve machine performance The book features two new editors, one from academia and one from a metrology intensive user industry, many new authors, and known experts who have grown with the field since the last version.

Furnishing case studies from a wide range of installations, the book details how CMMs can best be applied to gain a competitive advantage in a variety of business settings. Specification of Design Intent: Introduction to Dimensioning and Tolerancing, Edward Morse. Pereira and Robert J. Measuring targets are several distances and geometrical features on flat and cylindrical elements. These 3D artefacts were chosen for the availability in different colours and because optical sensors are commonly used measuring such deformable polymeric workpieces.

An experimental investigation was performed before the circulation in order to ensure the stability of the selected 3D artefacts, giving good results [10].

Of particular interest is the calibration of the 3D artefacts. Since they are made of polymeric material, they are not suited for calibration with tactile measuring systems, because of the non-rigid nature of the material itself.

Therefore, it has been chosen to develop a task specific measuring procedure using an optical technique [10]. In this case, a high-precision multisensor measuring system has been used at DIMEG for the calibration, applying the method of multiple measurement strategy resulting from the Draft ISO [11]: the calibrated values obtained with this method have been used as reference.

As main requirement of the comparison, the artefacts stability has been checked during the circulation, repeating the calibration before, in the half and after the circulation. From the metrological point of view, the glass scale and the hole plate are well-known and the reference values obtained during the circulation proved the stability of the artefacts, with deviations within the measurement uncertainty.

The plastic bricks were new items for use in metrological comparisons and their stability was particularly monitored during the VideoAUDIT comparison. Table 2 shows, as example, the results of the calibration of the white brick before and after the circulation. Table 2: Example of calibration results for the white plastic Brick.

2nd Edition

All the documents were available to the participants at the Website of the comparison: www. To preserve the confidentiality of the results, an identification number has been given to each participant to compare the measuring results without being recognizable by others. For each artefact a proper measuring procedure has been studied in order to extract a great number of information from the measurements and, when possible, to make the measurement feasible for the different sensors involved.

Table 3 resumes the features that were asked to be measured.

To limit the dispersion of the measuring results, and to have the results comparable, the alignment and the position of the acquisition points have been exactly defined in the measuring procedures. For the same reason, the participants were also asked to determine all the measurements based upon a least- squares calculation. Only for the diameter and the roundness of one hole on the 2D artefact the strategy has been left to the own choice of the participants Table 3.

Also the coefficients of linear thermal expansion CLT were stated in each measuring procedure for each artefact, so that the participants could use the CLT values for calculating the thermal compensation and the uncertainty of the compensation itself.

Table 3: Required measurements. Glass Scale Hole Plate Polymeric Bricks 4 point to point distances 1 distance between 2 holes Dimension 10 bidirectional lengths 1 point to plane distance 3 internal diameters 1 external diameter X,Y coordinates of 25 X,Y coordinates of 8 Position - holes centres knobs centres Roundness - 3 internal roundness 1 external roundness Flatness - - 1 flatness Straightness - - 4 straightness Perpendicularity - - 1 between two sides Parallelism - - 1 between two sides The measuring procedures for the 1D and the 2D artefacts were defined like procedures for interim checks of optical CMMs.

High speed coordinate measuring machine

Going into detail, for the glass scale, 10 bidirectional lengths have been requested, following the procedure indicated by the draft ISO [12]. In this case, only one repetition of the measurements was asked, without requiring a specific position of the artefacts on the working volume.

For the 2D artefacts, the participants were asked to determined the X,Y coordinate of the centres of the 25 holes, using the same alignment used for the hole-plate calibration, following two different paths as reported in Fig.

In this way not only geometrical errors of the machine can be determined, but also the effects of drift or hysteresis errors [9]. In the first, for each measured feature, the deviation of the measurement performed by the participant respect to the reference value was plotted together with the stated uncertainty.

The results of all the participants were plotted in a diagram in order to compare the results with the reference value as well as with the results of other participants. An example of this kind of diagram is shown in Figure 3.

To get the results comparable, for the participants that have performed more than one measurement for each features, the mean values have been plotted. If a result is only shown with a dot, this implies that no uncertainty was stated by the participant.

In the second kind of reporting, the results are compared putting more attention to the stated uncertainty. One way to do that is to calculate the normalized error EN-value that combine deviation and uncertainty into one number.

Coordinate Measuring Machines and Systems

This is very useful to communicate the quality of the results to the participants. Of course a very big stated uncertainty also causes small EN so in this case the normalized error might give an erroneous picture of the situation. The EN values have been calculated only for the companies that have stated an uncertainty.

Together with the overall comparison results, the results of each single participant have been analyzed separately in order to show to the single participants the information reachable by the measurements of the single artefacts. For the participants that have measured the glass scale in different positions, a report for each position has been produced to allow the identification of the specific scale error and eventually to evaluate the squareness errors.

In the case of the Hole Plate measurements, also a map of the geometrical error in the XY plane has been calculated and presented to each participant. As shown in the following, from the analysis of the plastic bricks other information have been collected, including influence of optical properties of the object to be measured. The participants have shown different capabilities in the measurements of the artefacts, in some cases measuring only some of the artefacts Table 4.

Only one participant was not able to measure any artefacts. Table 4: Numbers of companies that have measured each artefact. Probe orientation for coordinate measuring machine systems using design models. Circular test for three-coordinate measuring machines and machine tools. Optimizing a servo system for a coordinate measuring machine.

Measuring head for measuring equipment, multi-coordinate measuring instruments, and machine tools.

Optimization of the measuring path on a coordinate measuring machine using genetic algorithms. Universal high precision reference spheres for multisensor coordinate measuring machines.

Measuring Speed. Measuring machine. The modular instrument, Statograph S, incorporates microcomputercontrolled module functions. In conjunction with the controller as the central operating, display and control unit, this test system offers sophisticated test signal evaluation and documentation.

Both static transmitters, eg. Clearance compensation is incorporated for automatic correction of the test sensitivity if the probe clearance changes, and the signals of the individual test channels can be processed separately for flaw statistics, eg for process inspection.Measuring targets are several distances and geometrical features on flat and cylindrical elements.

Measuring machine.

Coordinate Measuring Machines and Systems

In the case of the Hole Plate measurements, also a map of the geometrical error in the XY plane has been calculated and presented to each participant. Traceability can generally be achieved by a calibration of the measuring device resulting in a calibration factor or in a calibration curve: this in true for simple instruments, but for universal measuring systems as CMMs this can be not applicable.

Styli for Probes Renishaw offers a comprehensive range of precision-engineered styli for maximum measurement accuracy.

The final composition of the participants is shown in Table 1. The third axis of movement Z axis is provided by the addition of a vertical quill or spindle which moves up and down through the center of the carriage. The plastic bricks were new items for use in metrological comparisons and their stability was particularly monitored during the VideoAUDIT comparison.

From this figure it is possible to see the influence of the optical properties of the objects Plastic Bricks in this case on the measuring results. An eBook version of this title already exists in your shopping cart.