Calypso Advanced Training [PDF]

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Carl Zeiss 3D Metrology Services GmbH

Training manual

Calypso Software Revision: 4.8

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4.8

Advanced Training

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© Carl Zeiss 3D Metrology Services

This manual is copyrighted. No part of this documentation may be copied, reproduced, translated or processed, multiplied or transfered by means of electronic devices without the expressive approval by Carl Zeiss 3D Metrology Services GmbH. Non-compliance will be prosecuted. All documents in this manual are compiled in concordance with the respective copyrights. If there are parts of this manual that indicate foreign copyrights, please inform Zeiss accordingly at info@ zeiss3d.de. All rights reserved, especially in cases where a patent is granted or a utility model is registered. This manual is subject to modifications. Carl Zeiss 3D Metrology Services GmbH will not be held liable for this manual, including the implied warranty for commercial quality and suitability for a certain purpose. Carl Zeiss 3D Metrology Services GmbH will not be held liable in any case for errors, accidental damages or subsequent damages arising from the provision, function or use of this manual. All product names are registered trademarks or trademarks of the respective proprietors. © Carl Zeiss 3D Metrology Services GmbH. Heinrich-Rieger-Str. 1 73430 Aalen Software revision: Calypso 4.8 14th Edition, January 2009



Calypso Advanced Training

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Customer Training Calypso Advanced Training Calypso Rev. 4.8 Subject no. 000000-1135-608

Prerequisites:

This class:

- Calypso Basic Lesson

- Covers additional Calypso functions - lasts 5 days - is recommended in one of our training centers - starts at 8 am and ends at 4 pm, - Self-made exercises without a coach possible after 4 pm - provides class-relevant documentation Understanding

Understanding

Review • Questions from the basic class • Questions from the practical use

Offline programming with CAD functions • - Calypso Basic Lesson • Simulation on the CMM or the offline PC • Optimized programming with resources • Strategy settings • Styli • Programming with CAD model • CAD import and resources

Coordinate systems    • Alignment with offset plane • 3 Aalen, Germany • RPS best fit method • Creating a base alignment as per DIN ISO 5459 • Start system • RPS best fit method •

Measurement methods, Part 1 • Gauß, Minimum, Tangential elements• • Filter and outliers • Form test • Different scanning procedures • Editing methods

  

Calculations, operations and evaluations • Recalls • Special calculations • Introduction to form and position

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Calypso Advanced Training

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Expanded programming functions • Patterns • Linear pattern • Circular pitch • True position on circular pitch • Pattern measurement as per DIN 3960 • Result element • Formulas • Result element • Relatively positioned probings

Understanding Understanding    Automation interface    • Pallet measurement, serial measurement Printout setup • Graphic illustration - plotting • Settings with form plot • Printouts • Modifying the printout header • User-defined printout

Stylus systems and accuracy • Automatic qualification • Special styli • Styli monitoring • Holder position functions • Analyzing measurement inaccuracies

  

Measuring methods, part 2 • Scanning with unknown contour • Scanning with 2 styli • Point masking in open scanning paths • Self-centering probing • Safety Cube • Park position • Missing bore

Exercises

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Review • How the trainer evaluates the class • How the participants evaluate the class

Special training or workshops are offered to teach more Calypso program options.



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  

For example: Training option curve, 3 days Training option PCM, 3 days Training planner / simulation Workshop Auto-Run Workshop Form and Location

Calypso Advanced Training

© Carl Zeiss 3D Metrology Services

Content Offline Programming with CAD Functions.............................. 8 1.1 Calypso Configuration............................................................................................. 9 1.1.1 Simulation on the CMM PC...............................................................................................9 1.1.2 Simulation on the offline PC...........................................................................................10 1.2 Optimized programming with resources........................................................... 11 1.2.1 Filter and outlier resources . ...........................................................................................12 1.2.2 Strategy resources..........................................................................................................12 1.2.3 Preassigning the stylus system for measurement plan.....................................................13 1.2.4 Copying the format: Changing the coordinate system with the "paintbrush"..................14 1.2.5 Coordinate system preassignment..................................................................................15 1.3 Programming with CAD model ........................................................................... 16 1.3.1 Working on the model . .................................................................................................17 1.3.2 CAD import and resources .............................................................................................23 1.3.3 Additional functions.......................................................................................................27

2: Coordinate system........................................................... 28 2.1. 2.2 2.3 2.4 2.5 2.6 2.7

Alignment with offset plane.............................................................................. 30 3D best fit method on the exercise cube........................................................... 33 RPS best fit method on the exercise cube......................................................... 35 Creating the base alignment as per DIN ISO 5459............................................. 36 Start System ..................................................................................................... 38 Maintaining the feature position....................................................................... 40 RPS best fit method........................................................................................... 41

3: Measuring methods, Part 1.............................................. 42 3.1 3.2 3.3 3.4 3.5 3.6

Calypso Advanced Training

Gauß, Minimum, Tangential elements .............................................................. 43 Filter and outlier basics..................................................................................... 44 Form test on the roundness example................................................................ 50 Automatic calculation of the scanning parameters............................................ 51 Self-made changes to the scanning and evaluation parameters........................ 53 Editor................................................................................................................ 55



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4: Calculations, operations and evaluations......................... 56 4.1 Recall.................................................................................................................... 57 4.1.1 Point recall from polyline................................................................................................57 4.1.2 Point recall from the circles.............................................................................................60 4.1.3 Point recall from cylinders...............................................................................................61 4.1.4 Point recall from curve....................................................................................................64 4.1.5 Point recall from a file.....................................................................................................65 4.2 Special calculations............................................................................................... 66 4.2.1 Measuring features.........................................................................................................66 4.2.2 Limiting freedom degrees...............................................................................................69 4.2.3 Changing the tolerance mode.........................................................................................71 4.2.4 Tangents........................................................................................................................74 4.3 Introduction to form and position......................................................................................75 4.3.1 Flatness, cylinder form....................................................................................................75 4.3.2 DIN position of two bores...............................................................................................77

5: Expanded programming functions................................... 78 5.1 Pattern.................................................................................................................. 79 5.1.1 Linear Pattern.................................................................................................................80 5.1.2 Polar pattern offset.......................................................................................................83 5.2 True position on circular pitch........................................................................... 88 5.2.1 Coordinate system from bore pattern best fit method...................................................91 5.3 Pattern measurement as per DIN 3960............................................................. 93 5.3.1 Circular pitch..................................................................................................................93 5.3.2 Linear pattern.................................................................................................................97 5.4 Formula............................................................................................................. 98 5.4.1 Result Element..............................................................................................................98 5.4.2 Probing a sheet metal.................................................................................................100 5.4.3 Probing positions relative to a feature.........................................................................101 5.4.4 Alignment with offset plane via formula......................................................................102 5.5: Automation interface...................................................................................... 105 5.5.1 Pallet measurement: . .................................................................................................105 5.5.2 Serial measurement: . .................................................................................................105

6: Result display - printout design...................................... 108 6.1 Graphic display - plotting.................................................................................... 109 6.1.1 Flatness and graphic display..........................................................................................109 6.1.2 Settings of form plot.....................................................................................................114 6.1.3 Plot output only if tolerance range is exceded...............................................................115



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6.2 Printout............................................................................................................... 116 6.2.1 Modifying the printout header......................................................................................117 6.2.2 Changing the printout header for plots.........................................................................119 6.2.3 Changing compact printout header..............................................................................119 6.2.4 Total result...................................................................................................................120 6.2.5 One-line custom printout..............................................................................................121 6.2.6 User-defined printout...................................................................................................125 6.2.7 Attaching a comment to the characteristic ..................................................................128 6.2.8 Inserting a text element................................................................................................129 6.2.9 Groups in the custom printout......................................................................................130 6.2.10 Saving printouts..........................................................................................................131 6.2.11 Changing the INI file for printout header data.............................................................133 6.2.12 Inserting a variable into the printout...........................................................................136

7: Stylus systems and accuracy.......................................... 138 7.1 Automatically qualify stylus system afterwards.................................................. 139 7.2 Special styli......................................................................................................... 142 7.3 Stylus monitoring................................................................................................ 146 7.4 Rack preassignment ........................................................................................... 148 7.5 Qualify the stylus change rack into the CNC....................................................... 149 7.6 Avoid measurement inaccuracies........................................................................ 150 7.6.1 Temperature compensation..........................................................................................150 7.6.2 Behavior in case of collisions.........................................................................................152 7.6.3 Clamping Workpieces for Measurement.......................................................................153 7.6.4 Stylus Systems..............................................................................................................155 7.6.5 Inaccuracy with a CMM................................................................................................158 7.6.6 Inaccuracy Analysis.......................................................................................................159

8: Measuring methods, part 2............................................ 161 8.1 8.2 8.3 8.4 8.5 8.6 8.7

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Scanning with unknown contour..................................................................... 162 Scanning with 2 styli....................................................................................... 163 Point masking in open scanning paths............................................................ 165 Self-centering probing..................................................................................... 166 Safety cube...................................................................................................... 168 Park position................................................................................................... 171 Missing bore.................................................................................................... 172



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Offline Programming with CAD Functions

1.1 Calypso Configuration............................................................................................. 9 1.1.1 Simulation on the CMM PC...............................................................................................9 1.1.2 Simulation on the offline PC...........................................................................................10

1.2

Optimized programming with resources........................................................... 11

1.2.1 Filter and outlier resources . ...........................................................................................12 1.2.2 Strategy resources..........................................................................................................12 1.2.3 Preassigning the stylus system for measurement plan.....................................................13 1.2.4 Copying the format: Changing the coordinate system with the "paintbrush"..................14 1.2.5 Coordinate system preassignment..................................................................................15

1.3 Programming with CAD model ........................................................................... 16 1.3.1 Working on the model . .................................................................................................17 1.3.2 CAD import and resources .............................................................................................23 1.3.3 Additional functions.......................................................................................................27



Calypso Advanced Training

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1.1 Calypso Configuration This section shows how to easily program with standard Calypso without the planning and simulation options. Goal of this section: • Switching in simulation mode • - Calypso Basic Lesson • Safe manual input of features and strategies • Changing the nominal geometries • Preparing styli in simulation mode • Programming on the CAD model • Simulated CNC runs

1.1.1 Simulation on the CMM PC Every Calypso PC can be programmed offline. Two possibilities: • with an existing connection to the CMM, by clicking "simulation mode", bears the risk of collisions at CNC start, Existing stylus data is used.

• Connection with simulation is used to be able to also start sequences. Here, the stylus data must first be created. Switching on simulation mode: 1. Disconnect existing connection: Close the stoplight window 2. Extras - workroom - control: Simulation: create connection. Caution: Check all simulation settings to match the machine settings. Make sure that you are working in simulation mode! If you are not in simulation mode you will change the stylus data and there is a risk of collision!

Calypso Advanced Training



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1.1.2 Simulation on the offline PC The programming station is a stand-alone Calypso PC, where remote machine measurement plans are created. The installation of Calypso on the PC was performed as a "simulation". The workroom houses the measuring device used later, although no control is connected to it. But the stoplight window is present, because measurement plans can be started. Caution: Check all settings of the simulation so that they conform to the online device settings.

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1.2 Optimized programming with resources This section describes the possible settings for quick programming with default values and system settings. 1. Filter and outlier resources 2. Strategy settings 3. Preassigning the stylus system for measurement plan 4. Preassignment of coordinate system 5. Copying the format: Changing the coordinate system with the "paintbrush"

The table represents possibilities for resources , not changes for individual features/characteristics/ runs Resource

Change with

Measurement Probing path

Extras - workroom - measurement

Clearance

Extras - workroom - measurement

Clearance plane

Can be edited by means of editor or feature

Rounding locations

Extras - workroom - measurement - nominal value

Preassignment of coordinate system

Extras - workroom - measurement - nominal value

Tolerance mode

Extras - workroom - measurement - nominal value

Filter / outlier

Prepare - resources

Strategy settings

Prepare - resources

Styli

Preparing - styli

Coordinate System

Prepare - preassignment for new features

Printout Print output

Resources - define printout

Print output - files

Resources - results to file

File name for output file

Resources - names for output file

Feature evaluation

Resources - presentation of features

Feature - naming

Extras - workroom - work environment- IndicationNames

CNC CNC

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CNC - preassign CNC start values

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1.2.1 Filter and outlier resources 1.2.2 Strategy resources These resources can be used to quickly extract already finished features with settings from the CAD model. The following possibilities exist: • Defining and saving filter and outlier settings • Defining and saving strategy settings • Saving both types of settings together A data file is created for each of the mentioned cases. This can be found at . . . \Zeiss\Calypso\home\om\config\ rules\ . . . Calypso will always access this path automatically.

Task: • Define the filter and outlier resources as shown. Save these under the name "AufbauSchulung_Filter" (AdvancedTraining_Filter) • Define the strategy resources and save these under the name "AufbauSchulung_Strategie" (AdvancedThe following applies to the filters/outliers: The setting of the current measurement plan is changed. The following applies to the strategy: The default setting for new features is changed for every measurement plan. With an update from former Calypso versions, this equals existing functions.

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• Click on "General" and save both under the name "AufbauSchulung_Alle" (AdvancedTraining_All)

• Open a new measurement plan, load the model "Scanmax.sat" and program the following task. Goal: Program the sequence CNC with as few mouse clicks as possible.

1.2.3 Preassigning the stylus system for measurement plan Use this very convenient function with your programming: If geometries are extracted from the CAD model, you need not worry about styli. They can be assigned automatically later by: Resources -> Stylus System -> Preassign the stylus system for measurement plan autom.

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1.2.4 Copying the format: Changing the coordinate system with the "paintbrush" The "paintbrush" changes the properties of objects, the assignment of a coordinate system is one of the properties.

Task: Create a 2nd coordinate system in the center bore. Assign a new coordinate system to the circles (1-6) without opening the features.

Assign the new coordinate system to the first of the circles.

Select the "Paintbrush - transfer format" . Only select "coordinate system“.

Now select the five other circles, which are also to be transferred to the coordinate system (circles 5 - 7).

Close by clicking OK.

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1.2.5 Coordinate system preassignment

This function can be used to determine which coordinate system the subsequent measuring features are to be calculated in. Retrieval:

Resources - preassignment for new features

Select the desired coordinate system. Do NOT close this window. The assignment is only made for the features that are measured or determined while the window is open.

Preassignment for the projection plane The function can also be used for projection planes.

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1.3 Programming with CAD model Depending on the respective CAD program, the CAD files are written in a specific format. There is a difference between • manufacturer-specific data sets such as ProE • system-neutral data sets such as STEP. Furthermore, there must be a differentiation between 2D and 3D data: • 2D data is based on vector-oriented drawing programs and it produces two-dimensional data. This data can be used for programming in Calypso. • 3D data sets deliver geometry data for a volume model. Wire models, surface models and volume moduls are the basis for programming with Calypso. The decisive factor is often the quality of the delivered data. Incomplete or faulty constructions of surfaces in the model complicate the programming of the measuring run. Therefore, controlling the model is always the first step when working with CAD files.

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1.3.1 Working on the model

Note: A larger version of this drawing can be found in the Appendix.

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Loading and controlling the model The exercise workpiece is loaded as an Acis model and rendered to check for completeness. The position of the basic system stems from the design phase. If the position does not meet the requirements for measurement, the model must be moved.E

Adapting the origin and the axis directions Here, the Calypso offers two possibilities: • Manually transforming the model • Directly creating the base alignment In this example, the model is first manually transformed and the coordinate system is created afterwards. Manually transforming the model

Moving the model by 180 mm

Rotating the model by -90°

Base alignment in desired position

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Selecting features and defining solid geometry Defining a solid geometry means: individually extracting known spatial geometric features from the model. Here, the dimensions and the name of the feature (for some formats, as indicated by the designer) are made available for Calypso. Furthermore, the creation of circles, straight lines and points is possible. These, however, are not spatial features and must therefore be selected separately. Modifying the model Clicking the cone: Here, you can see that only one half has be stored. This means, that a model revision would make sense. After the reworking, here "merge faces with same geometry", the cone and all other features can be extracted correctly.

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Measuring on the CAD model Features for the base alignment: The base alignment is to be created from three planes. These planes are extracted as solids. After that, the planes are equipped with strategy (probing points) and entered into the base alignment.

The safety cube is defined with the function "safety cube of CAD model". The edge distance of 10 mm is sufficient.

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Strategy Defaults: This procedure defines the measuring strategy of the transfer or creation of measuring features when extracting from the CAD model.

Example: Plane with multi polyline Strategy defaults can be set for every feature on this list. Here, for example, the multi polyline is set for a plane and the top plane is re-extracted.

Based on these settings, this plane features a scanning path along every border.

This plane can now be used for characteristics that require the form of this surface, e.g. the perpendicularity to the side surface.

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Additional menus and settings "View' menu This menu can be used to make settings and save some data. Note: Details regarding these functions can be taken from the operating instructions. "Display" menu (CAD model control) This function can be used to alter the display in the ACIS window.

Modifying CAD features This menu point covers a multitude of functions, only some of which are presented here. • • • •

Deleting features and rendering them invisible Creating features from the wire model Positioning the model Cutting the model

Example: Creating elements from the wire model Principle: • Switch on the wire model • Click on a contour • Click the respective button • Clicking a circle creates a circle, clicking two circles creates a cylinder • Offset to move the generated feature • Curves with preset point numbers • Spatial points at preset position.

Note: These functions and many more are the subject of the training seminar "Planner and Simulation"

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1.3.2 CAD import and resources Data transfer of CAD programs to Calypso Calypso works with the ACIS format of the Spatial company, which uses data with the extension *.sat or *.sab. In order to preserve this format, different methods can be applied: 1. Calypso imports the respective original data format via an import filter. (=direct import) 2. Calypso imports a conversion format such as STEP. For this, the CAD system exports into this format from its original format (e.g. STEP). 3. The CAD program exports the ACIS format for Calypso directly. Neutral data formats: VDAFS: Developed by the "Verband deutscher Automobilbauer" (Association of German Automobile Manufacturers), a very important format in the past. IGES:works with 2D and 3D data, when imported into Calypso, there can be problems due to the inaccuracies in the original. STEP: Modern, internationally used format, which converts volume models with nearly zero losses and which can contain additional information such as mass. This format is the preferred choice. Important: CAD programs often allow different export settings.Here, one must experiment with the correct export setting to achieve optimized results in Calypso.

CAD model file formats Currently, Calypso supports the following file types: ACIS files CATIA files CATIA V files Drawing interchange format STEP files IGES files VDAFS files Unigraphics ProE Parasolid Inventor Solidworks IDEAS

*.sat or *.sab *.exp, .model *.CATPart *.dxf *.stp *.igs *.vda *.ug *.prt *.x_t *.ipt *.sldprt, .sldasm *.idi

What is important during the import is that the file extension is correct, as Calypso recognizes the file type via its extension.

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© Carl Zeiss 3D Metrology Services Importing a model The CAD model can be located on any file path. You can access the respective directory via . You can always import *.sat files with "file type". Additionally, one or more import filters can be released. The respective files are only shown if you switch to the respective file type.

In this example, the always included ACIS model of the exercise cube is loaded.

Problems while loading? Problems during the loading process are multi-facetted and can be difficult to eliminate. • Type of data set correct? A file extension does not necessarily have to be correct, there could have been retroactive changes. Be careful with unknown file formats. • Does the data set version match the Calypso converter? • Check the interface. Is the correct interface unlocked in Calypso? • Is the data set really a volume model, not just a drawing saved as a model? • If the model is visible, but features additional auxiliary lines, these can be deleted. • If the CAD model does not appear on the screen, the window Scheme ACIS Interface Driver extension in the taskbar might contain additional information. Also, a log file with the model name will be created. This file contains additional information and possibly a list of errors.

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Examples for faulty loaded models:

Automatic healing The model can be adapted in four steps by means of the Resources > characteristics settings editor - group in custom printout)

Example with a larger font for group names:

Note: Here, the display of groups in the printout must be set to "ON".

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Measurement plan editor - characteristics Groups in the custom printout: ON

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6.2.10 Saving printouts The saving process will be explained using the example of the compact printout: Resource The compact printout is saved as a text file. Name of the text file:"cprotokoll.txt" in the measurement plan directory: ...calypso\opt\om\workarea\inspections\ Printouts can be saved in any desired way via the following function: Selecting the name assignment.

Indication of the path and the name convention: The file name and the path can be combined from the fields of the printout header, syntax as per PCM convention. If the file name does not contain a path, the standard path is used, otherwise, the path from the defined name.

Possible output files 1. 2. 3. 4. 5. 6.

Calypso Advanced Training

Default printout Compact Printout 3 table files (hdr,chr,fet) pdf files (graphic, text) DMIS QDAS

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© Carl Zeiss 3D Metrology Services Output of ASCII files with the extension *.txt: The compact printout and the default printout can be output using this method. Output in PDF format with the extension *.pdf: PDF file graphic: PDF file text:

puts out the custom printout puts out the compact printout

Exercise: Define the output of the compact printout and the custom printout as a *.pdf file to the "Temp" directory. Keep in mind, that different names will be assigned. The name should be composed as follows:

Measurement plan name + date + part number

PDF file graphic: "C:\TEMP\"+getRecordHead("planid")+getRecordHead("date")+"_Teil_"+getRecordHead(" partnbinc")+"praes.pdf"

PDF file text: "C:\TEMP\"+getRecordHead("planid")+getRecordHead("date")+"_Teil_"+getRecordHead(" partnbinc")+"praes.pdf" Note: The option PDF must be set to "ON' in the menu "Resources - results on file". PDF must be activated in the CNC start window to output PDFs!

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6.2.11 Changing the INI file for printout header data If a file "userfields.ini" is present, Calypso will take from this file which data will be queried in the dialog box "input parameters" and which values can be captured for the individual printout header parameters. The settings in this file overwrite the settings of the possibly present file userfields.txt. The file "zzz_userfields.ini" was included in the initial install (this file contains an example for user-defined printout header fields). You activate the delivered file "zzz_userfields.ini“ by renaming it to "userfields.ini". The further description of the *.ini file can be taken from the operating instructions.

In this section , there will be an example for a change: Create a arbitrary formatted printout header with the following new fields: • • • •

Month Day of the week Edited by Editing machine

These fields should be completed as pulldown menues during the start of the program.

The next two pages show a "userfields.ini" file with explanations.

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© Carl Zeiss 3D Metrology Services REM this is an example for the "userfields.ini" file. [Field names] REM userfield names must always begin with "u_".!! REM e.g. u_hallo_1, u_protocol, u_test REM REM REM REM

;

***************************************************** **nach REM und ; Texte und Meldungen ** ** werden vom Programm nicht benötigt ** *****************************************************

u_field_1 u_field_2 u_field_3 u_field_4 u_field_5 ; Definierung des ersten userfields mit dem Namen „u_field_1“ [u_field_1] name=Monat editMode=true runMode=true selectiveList=true selectiveListValues=u_field1_valueList editable=true defaultValue=1

/ Name des inputfield/list ;; ifBezeichnung this field is confirmed with "true", it will appear with the Wirdparameters. dieses Feld mit „true“ bestätigt,erscheint es bei den ;; edit ;; ifEdit thisParametern. field is confirmed with "true", it will not appear with the Wirdparameters dieses Feld mit „false“ bestätigt,erscheint es nicht ;; start bei den Parametern ;; This list isStart either a pulldown menu or a Diese Liste ist entweder ein Pull down menue oder eine :; box combo box. parameters for this list can be found in the ;; The selected Die selektier Parameter für diese Liste findet man in den ;; profiles with the name "u_field1_valueList" mitis dem namen „u_field1_valueList“ ;; Ifprofilen this field labeled "false", there is no input possible in the Ist dieses Feld mit „false“ ist keine Eingabe in der ;; created combo box. With benannt "true", the entstehenden box ;; editable combocombo box will bemöglich. created. mit „true“ entsteht die editierbare combo box.in the created field first, is the ;; The value that appears Der Wert erzeugten ;; value withder theim option name Feld "1" zunächst erscheint ist der ; Weet mit dem optionsname „1“

REM Hier wird die Eingabeliste für das Userfeld ( Pulldown menue ) mit dem Namen „Part“ definiert. [u_field1_valueList] REM Nach dem = sind beliebige Namen möglich. 1=Januar 2=Februar 3=März 4=April 5=Mai 6=Juni 7=Juli 8=August 9=September 10=Oktober 11=November 12=Dezember

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Ebenfalls ein Standartwert zu erkennen option defaultValue ; You will also detect a standard value option default value ; Defined Definiertby durch u_field_1 u_field_1

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REM Definition of the second user field with the name "u_field_2" [u_field_3] name=Bearbeiter editMode=false runMode=true selectiveList=false editable=false defaultValue=Meier

dieses Feld mit „false“ bestätigt,erscheint es nictwith bei the ; if; Wird this field is confirmed with "false", it will not appear ; Editparameters. Parametern. ; edit dieses Feld mit „true“ bestätigt,erscheint bei den ; if; Wird this field is confirmed with "true", it will appeareswith the ; Startparameters Parametern ; start ; Keine Liste ( Pullmenu) down menue) ; No list (pulldown ; keine(combo ( combo box ) ; none box) ; Dieser erscheint Eingabefeld bist er ;This valueWert will appear in so thelange inputim field until it is changed. ; geaendert wird.

[u_field_2] name=Wochentag editMode=true runMode=true selectiveList=true selectiveListValues=u_field2_valueList editable=false defaultValue=3 [u_field2_valueList] 1=Montag 2=Dienstag 3=Mittwoch 4=Donnerstag 5=Freitag 6=Samstag 7=Sonntag [u_field_3] name=Bearbeiter editMode=false runMode=true selectiveList=false editable=false defaultValue=Meier [u_field_4] name=Bearbeitungsmaschine editMode=true runMode=true selectiveList=true selectiveListValues=u_field4_valueList editable=true defaultValue=D12

; if; Wird this field is confirmed with "false", it will not appear dieses Feld mit „false“ bestätigt,erscheint es nictwith bei the ; edit ; Editparameters. Parametern. ; if; Wird this field is confirmed with "true", it will appeareswith the dieses Feld mit „true“ bestätigt,erscheint bei den ; start ; Startparameters Parametern ; No list (pulldown ; Keine Liste ( Pullmenu) down menue) ; none box) ; keine(combo ( combo box ) ; This value willerscheint appear inso the inputimfield until it is bist er ; Dieser Wert lange Eingabefeld

[u_field4_valueList] 1=D12 2=D13 3=D14 4=D15 [u_field_5] name=Currency editMode=true runMode=true selectiveList=true selectiveListValues=u_field5_valueList editable=true defaultValue=Euro

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6.2.12 Inserting a variable into the printout This task can only be performed with the PCM option. The exercise consists of selecting the "part number incremental" from the variables of the printout header, which are known from previous exercises and to insert them as a comment into a characteristic. Keep in mind that this example is only intended to give you an idea of the complex operation possibilities of variables by means of formulas. Think of your own applications to deepen the subjects.

Sequence: Take another diameter from the previous example, open it and delete the comment. Click into the comment field on the right and select "Formula". Enter into the formula field:

The function "getRecordHead()" reads a variable from the list of the printout header variables, here the variable "partnbinc". This is the part number incremental. The printout now puts out the part number in the comment.

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CAD file -> Convert CAD entities With this function, CAD files can be converted into *.sab files in the background. The selected files are converted in the background and saved once more under their name with the extension *.sab in the same directory. The printout of the conversion is saved under the file name with the extension *.log in the same directory. A background conversion can diminish the performance of the applications running in the foreground. You can select multiple files.

CAD file -> CAD model comparison Compares models, e.g. after drawing modifications. This function is to be considered an auxiliary function only, as CAD programs can better perform this comparison on their own.

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7: Stylus systems and accuracy

7.1 Automatically qualify stylus system afterwards.................................................. 139 7.2 Special styli......................................................................................................... 142 7.3 Stylus monitoring................................................................................................ 146 7.4 Rack preassignment ........................................................................................... 148 7.5 Qualify the stylus change rack into the CNC....................................................... 149

7.6 Avoid measurement inaccuracies........................................................................ 150 7.6.1 Temperature compensation..........................................................................................150 7.6.2 Behavior in case of collisions.........................................................................................152 7.6.3 Clamping Workpieces for Measurement.......................................................................153 7.6.4 Stylus Systems..............................................................................................................155 7.6.5 Inaccuracy with a CMM................................................................................................158 7.6.6 Inaccuracy Analysis.......................................................................................................159

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7.1 Automatically qualify stylus system afterwards Task: Stylus systems must be qualified beforehand. Creating a qualification measurement plan The star stylus must be requalified. This can take place in two different ways.

Method 1: With the button: Here, only the stylus system located in the probe head is qualified automaticallly.

Method 2: Via a measurement plan with characteristics for each individual stylus system. Functions as a regular measurement plan. Here, the stylus systems to be qualified can be selected.

Note: Many stylus functions depend on the probe head and are not shown here. Further information can be found in the document "Sensors".

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Method 1: • • • •

The reference sphere must be qualified. Only the stylus system located in the probe head is qualified. The mode of the original qualification is used. Navigation around the sphere are calculated automatically.

The printout shows these values:

Retroactive qualification while maintaining the Method 2 bending parameters (tensor) Resource: The star stylus (and possible additional stylus systems) should be present and qualified. Principle: • First, the master probe automatically qualifys the reference sphere at the most recently used position. • Then, the stylus systems are qualified in the order of the plan. • Single styli can be selected. • Stylus changes are performed automatically (except when the stylus is not assigned to any holder).

Open a new measurement plan; and from the toolbox or the resources menu - utilities, insert as many entries "Stylus system qualification" as there are stylus systems - including master probe. Rename the characteristics. This does not assign the respective stylus! (see below).

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Open each characteristic, here for the master probe:

(1) Assigning the stylus system (2) Setting up the mode for this requalification (3) Selection of the stylus for (4) (4) Adding or removing individual styli for the "requalification“

Set up the adjustments for the master probe as shown.

Open the star stylus. Only select individual styli. Set the mode for each stylus to "Geometry - Requalification“.

Start the sequence CNC start window: "Use position points only" The CMM only runs the "6 point" mode for this "requalification". The tensor remains intact from the original qualification, the geometry values (sphere center points and diameters) are redetermined.

Caution: The mode "Use position points only" remains during the subsequent CNC start, even if another program is started! You must switch back to "use clearance planes", otherwise there may be severe collisions!

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7.2 Special styli Disc stylus Task: Qualifying the disc stylus and subsequent correction on the ring gage.

A disc stylus is not a complete sphere but a section of a sphere. The danger with working with the stylus are probings with the edge of the disc and not with the sphere section surface. The problem with qualifying is hitting the probings exactly at "equator height". For this reason, the diameter is corrected afterwards on one ring gage.

Procedure: 1: 2:

Qualify the disc stylus on the reference sphere Requalify on the reference sphere or on the ring gage Manual correction of the stylus data

3:

Re: Step 1: 1. Qualify the reference sphere with master probe 2. Insert the disc stylus and qualify in the "manual" mode with the "disc" geometry. 3. The first probing must now take place in the direction of the shaft of the installed disc; from this, Calypso will detect the shaft direction for this stylus pin. This probing will not be included in the calculation.

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© Carl Zeiss 3D Metrology Services The following probings must be made on the circumference. As this method is not sufficient for a very accurate qualification (bending parameter, point recording only on the circumference), you should requalify on the ring gage.

Re: Step 2: 1. Clamp the ring gage and align it. 2. Measure the circle in the ring gage. 3. Compare the circle diameter with the nominal diameter of the ring. 4. The diameter of the disc can only be corrected manually.

Re: Step 3: 1. Output of the diameter in the default printout. 2. The deviation from the actual diameter must now be corrected. 3. Open the stylus data and edit the radius. 4. Measure the ring gage again and check the diameter. 5. Perform another correction if necessary.

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© Carl Zeiss 3D Metrology Services Qualifying a slanted stylus • Qualifying a slanted stylus as per "eye measure" • Determining the shaft inclination with the cylinder feature • Requalifying with the correct vector data

Assemble a slanted stylus. Use this stylus as a new stylus. "Improvised" qualification Qualify the slanted stylus on the reference sphere. Mode: 6 points for the "improvised" qualification. Only with the "true" qualification with the then known angles will you need to work in the "tensor" mode.

"Probing in shaft direction" means: best possible probing as per eye measure from the shaft direction. The query for the angles of the shaft is displayed These are not known yet. Simply confirm with OK.

The stylus is qualified and measurements are possible. Close the stylus menu. Use the shaft of the stylus to probe eight points in two planes on the reference sphere.(see image)

A cylinder is recognized. The inclination of the cylinder axis, output via the projected angles A1 and A2 is determined by the inclination of the stylus shaft. The two angles A1 and A2 must be entered when the query appears with the subsequent "true" qualification (in the tensor mode).

This process ensures that Calypso uses a "semi sphere" to qualify under the correct angle, which is a resource for correct probings.

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© Carl Zeiss 3D Metrology Services Qualifying a cylinder stylus Sequence: • Qualifying the cylinder stylus in manual mode • Requalification on the reference sphere • Manual correction of the stylus data

Assemble a cylinder stylus. Measure the stylus in the "cylinder" mode, on the equator of the reference sphere, with three points each in two planes.

After you complete the qualification, you should switch to the features side. Measure a circle on the equator of the reference sphere. Compare the diameter of the circle with the diameter of the reference sphere. The deviation from the actual diameter must now be corrected.

Open the stylus data and edit the radius. (See disc stylus sequence)

Iterate this process if necessary.

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7.3 Stylus monitoring This function must be divided into two areas: Monitoring the CNC qualification Here, you will check for correct geometry, temperature and deviation (Sigma) during the qualification. Monitoring the styli during CNC start Here, you will check which styli are required for the CNC run, whether the stylus has been qualified, whether a stylus change position has been assigned to it or whether a manual stylus change is planned. The mode of the original qualification is used. Depending on the validity status, the run can be terminated or started or a warning message can be displayed. If one of these limits is exceeded, the stylus must be set to the "unqualified" status. Note: Further information can be found in the operating instructions or the online help.

Monitoring the CNC qualification Here, there are two possibilities: 1. Using global limit values. These are set via the workroom. They apply to every stylus that is qualified in the CNC run. 2. Setting stylus-related limit values. Here, the stylus-related setting overlays the global one. In both versions, the shown criteria are monitored.

In the workroom, you can globally preassign the limit values and the stylus test: Extras - workroom - CMM - stylus systems

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© Carl Zeiss 3D Metrology Services Checking the styli during CNC start Switching on the function: Resources - stylus system - stylus check at CNC start

You can set up the respective function in this self-explanatory menu.

Task: Set up the limit value in a measurement plan and test different termination criteria.

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7.4 Rack preassignment Here, a rack location assignment can be saved for each measurement plan. During CNC start, the correct assignment is checked. Note: Further information can be found in the operating instructions or the online help. Application 1. Creating and managing rack assignments The assignments are managed in the menu "Automatic stylus change" via "Administration". 2. Switch on function Resources - measurement plan - rack assignment

If the function is activated, there will be check when the measuring run is started whether the saved assignment matches the assignment in the stylus change rack. If the assignment does not match, there will be a message as to which of the used stylus systems should be mounted in which rack positon. The displayed assignment includes the holder location name, the holder location name and the stylus system name. Caution: The parameters entered under "approach parameters" are not saved. This means that those parameters that were active prior to loading are executed. This can lead to collisions.

Task: Allocate an assignment to a measurement plan and examine several application cases.

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7.5 Qualify the stylus change rack into the CNC This function allows the automatic qualification of the stylus holders in the CNC. This function is only required if the stylus change rack changes positions frequently, e.g. if it is mounted on a pallet, which is clamped onto different positions within the measurement volume. Further information pertaining to this unusual case can be found in the operating instructions or the online help.

Retrieval: Resources - utilities - qualification of stylus system holders

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7.6 Avoid measurement inaccuracies 7.6.1 Temperature compensation Calypso calculates the geometry of a workpiece for the material properties at 20°C. 20°C is the reference temperature for length measurements as per DIN EN ISO 1. If the temperature deviates from 20°C, the measured geometry data must be corrected. For this, the temperature of the CMM and the workpiece must be known. The respective expansion coefficient must always be entered manually.

Retrieval of the temperature compensation

The temperature compensation must be switched on first. They distinguish between two cases: 1. The CMM does not have a temperature sensor. When the temperature compensation is opened, the values for the workpiece and the ratio are at 20.000 °C . • Measure the temperature of the workpiece • Enter the temperature and the workpiece expansion coefficient. Corrections are performed automatically during the run. 2. Temperature sensors are connected. When the temperature compensation is opened, the current values for the workpiece and/or the ratio are displayed. • Select the connected sensors. If there are two sensors, the temperature will be averaged out. • Enter the workpiece expansion coefficient. Corrections are performed automatically during the run.

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Monitoring functions Calypso issues a warning during CNC start and in the printout if the limit values are exceeded. You must pay special attention to the temperature when qualifying styli. First, the temperature is saved along with the stylus data and can be taken into consideration here.. Furthermore, even temperature differences in the stylus caused by the heat of your hands must be avoided shortly before the qualification. Temperature effect with styli Expansion of the used materials: • Aluminum: Length change = 2.3 µm/degree • Titan: Length change = 0.6 µm/degree • Carbon fiber / ceramic: Length change = 0.1 µm/degree Example: Comparison of materials with a temperature difference of "only" 5° (Measurement began at 20°, end of measurement 25°, stylus length L= 200mm) • Aluminum extensions : Length change = 23 µm !!! • Titanium extensions : Length change = 6 µm !!! • Carbon fiber/ceramic extensions : Length change = 1 µm !!! Remedy: If you are expecting temperature fluctuations on the measuring device, use the components listed in the following, if possible in the listed sequence: • 1. Carbon fiber 2. 3. 4. 5.

Note: Temperature compensation cannot be used during stylus qualification.With temperature differences between the stylus qualification and the measurements on the workpiece, you must requalify the styli if necessary! Display the temperature in the printout header. The temperature can be displayed with the SYS parameter "temperatureworkpiece". Alternative, PCM can be used. The temperature can be compared at the beginning and the end of a measurement by means of the PCM and a message can be generated. More information regarding this subject is included in the PCM Calypso Advanced Training

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7.6.2 Behavior in case of collisions

With the characteristic "CMM Check", you can monitor your coordinate measuring device quickly, safely and as per standard (DIN EN ISO 10360 and VDI/VDE 2617).

The qualified characteristic "CMM Check" allows a quick and standardized monitoring of the CMM. The control and evaluation software allows an expressive evaluation by monitoring factors. Recommended monitoring cycle: or: After a collision

The following components of the CMM are monitored by "CMM Check": The probe head system (precision sphere, adjustment ring, reinforcement normal): • the variance of the probe head system, measured in relatively small meauring areas • the probing behavior of the probe head system, overlayered by the features of the CMM (oscillation, hystereses, dynamic deformations) • the scanning features of the probe head system. The CMM Geometry • the variance in the entire measuring volume of the CMM, caused by the straightness variance of the guides and their perpendicularity to one another • the length measuring variance (end dimension 40 mm / end dimension 400 mm) • the CMM as form measuring device including its filtering functions The rotary table (2 precision spheres as options) • the four axle movement for the CMM with rotary table • the sum of variances from the CMM geometry and component variance of the rotary table.

Literature Reference: „Genau messen mit Koordinatenmessgeräten, H.-G. Pressel, expert-verlag

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7.6.3 Clamping Workpieces for Measurement A manufactured workpiece must be positioned on the coordinate machine for measuring. Usually, a clamping machine is used to achieve this. The clamping machine is adapted precisely to the workpiece and fulfills the following functions: • Defining the Workpiece: Positioning features such as stops, linings, index pins, prisms, are used to place the workpiece into a certain position on the CMM. • Clamping the workpiece: Clamping features such as quick clampers, clamping claws, spring tensioners, hold the workpiece in the desired position during the measuring process. The determination and tensioning of the workpiece must ensure that the workpiece will not warp and that it does not move during the measuring procedure. A clamping of this type is called "statically defined". With "statically underdefined" clamping, the workpiece is still able to move (e. g. the rotating part of a prism without length stop). With "statically overdefined" clamping, the workpiece will be deformed/warped (e. g. clamping of a surface on four placement points). With statically defined clamping, the clamping features should be located as directly as possible across from the defining features. This will prevent deformations of the workpiece during the clamping process. Another important advantage of the statically defined clamping is also that the workpiece and the clamping machine can change with different temperatures, without bending forces influencing the measurement process. With statically overdefined clampings, where the workpiece is "pulled" into a forced position, bending forces will be generated with temperature changes, which deform the workpiece inside its clamping. The 3-2-1 clamping is a typical, statically defined clamping for prismatic workpieces (lathing pieces, housing. . . ). Three placements position the workpiece in the space (Z axis). Two stops prevent the rotation in the placement plane (Y axis) and one stop determines the position along the Y axis (origin). Chuck clamping is often used for rotating parts. Here, the prism defines the space axis (Z axis); the radial stop prevents the rotation around the Z axis and the length stop defines the position along the Z axis (origin). Defining features are made of hardened materials. They must allow a continuous repeatedly accurate position of the workpiece and must never close. Damages to the workpiece are avoided by a high surface quality. Examples for Defining Features: • Stops, placements • Pins • Prisms • Centering cones • three spheres (Bessel points for long parts, example: Portal check)

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Clamping features must provide the necessary tensile force during the measurement. They must not deform or damage the workpiece. They must not become loose during the measurement or during transport of the workpiece Examples for Clamping Features: • Claws, tensioning connections • Quick clampers (knee lever tensioners) • Screws, also with torque limits • Puddy, adhesive • Spring tensioner • Swivelling clamper • Magnets • Vacuum

Example for a Clamping Machine

Handling tips for Clamping Machines • Clean the surfaces where the workpiece is to be placed (defined) prior to clamping it. Also, you should keep the defining features of the machine clean. • After placing the workpiece into the machine, check whether the workpiece is shaking in the clamping. Dirt, shavings, burs on the workpiece and worn out defining features on the machine can jeopardize the safe tensioning. • Make sure that the clamping features are in their intended positions during the measurement. That way, collisions and damages on the stylus system can be prevented during measurement. • The workpiece should always be clamped in the optimized measuring range of the CMM, i. e. not along the edge. This requires a deep knowledge of your CMM. • With highly accurate measurements, you should avoid using magnets for clamping. The measuring result is falsified by the magnetic affect on the workpiece and the stylus system. • Use defined spring forces for clamping and defined torques for screwed connections (torque wrench).

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7.6.4 Stylus Systems Generally, you should make sure that a visual check is performed before stylus definition or measurement in order to check the cleanliness and integrity of the stylus features, styli and extensions. Extensions/connections/intermediate pieces: • Watch for cleanliness and damages to the insertion surfaces and possibly loose adhesive connections. • Tighten the screwed connections correctly and thoroughly (use only the intended tool, other Extras may cause damages) • Secure the permanent connections with extensions and intermediate pieces with adhesive. • Setup with as few individual parts as possible (extensions and intermediate pieces) per stylus. Prefer a special feature with directional changes and angled pieces ! Assembly configurations: • Sufficient wait time after the assembly and before the qualification to discharge the heat from the hands. >> Otherwise: qualification and accuracy errors!! Configurations/stylus lengths: • You must read the machine description!!! • Measuring probe head: Max. weight 600 g • Switching probe head: Max. weight 200 g !! Specialty: Symmetric placement of the mass !! • Note: Always use the stylus only as long as necessary and as stabile (rigid) as possible! • Probing sphere diameter as small as possible (reason: influence of the accuracy via the surface of the test object => mechanical filtering effect) • Use the stylus bending correction feature only with highly accurate measurements and/or long styli • We recommend a check on an ring gauge (D) and a form plot (v2) • Calibrating disc styli Based on the very small contact segment between the stylus and the sphere normal, we recommend a check on an ring gauge (D) and a form plot (v2)

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Checking the Stylus Data and Configurations Probing sphere diameter • We recommend a check on an ring gauge (D) and a form plot (v2) In case of deviations, perform a manual correction of the sphere radius. Probing sphere distances / diameters / quality of the stylus features used • Sphere measuring on sphere normal with the first stylus tip of a configuration. Determined center coordinates in XYZ are declared origins. • All other probing spheres are measured in reference to this origin and compared. • If the sphere normal is always in the same location, this means repetitive measuring. • If the sphere normal is physically offset, this is used to capture systematic errors on the CMM. • The creation of an automated run in the style of a measuring program "Stylus Qualification Check" to check the stylus data is recommended when multiple and/or complex configurations are used. Description of the Measuring Program "Stylus Qualification Check": • The measuring program is used to check the stylus data determined in the course of a qualification, manually or via a CNC program, or to check the long-term stability of the used styli in serial measurement, up until a new qualification of the styli. • The result of a measuring program run is the representation of the variances in the coordinates X, Y, Z, of all styli used and configurations of a stylus configuration group to the reference "ZERO" (origin), determined by means of the master probe or the first stylus of a configuration (master probe). • In addition, the sphere normal diameter is put out as a measure for the stylus diameter determined during the qualification. • The sigma value is an indicator for the degree of contamination, wear, damage or loosening of styli and stylus features, within a configuration. • The output is a measurement printout. • Changes in the stylus data can be detected by comparing the results of the individual measurement runs (printouts). • The results can be saved and evaluated via qs STAT (option) if a corresponding qs STAT interface is available. • By issuing the respective limit values with the permissible deviations of the individual parameters, the user's decision making process is facilitated. The size of the deviations and/or sigmas to the reference "Zero" depends on the following parameters: • Quality of calibration • Length and stability of the used styli and extensions • Degree of the temperature deviations and time temperature fluctuations on the CMM • Degree of contamination, wear, damage of the stylus spheres Existence of of loosened or damaged stylus and/or extension features.

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Causes of extensive qualification sigma values • After a hard collision with a stylus, in every case, a complete recalibration/requalification of the configuration is required. • Stability of the stylus components is not sufficient (e. g. incorrect shaft materials, faulty adhesive connections, screw on surfaces contaminated, damaged) • Stylus components not screwed together tightly enough. • Three point bearing on the probing head or the changer plate contaminated. • Stylus feature was mechanically damaged by improper treatment or hard collision. • Stylus layouts that are too long or too heavy are used (perm. limit values are exceeded). • Impedance by a magnetic field due to steel components used Stylus change machine / reproducibility: • Switching system = 1.0 µm on 200 mm • Measuring system = 0.25 µm on 200 mm

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7.6.5 Inaccuracy with a CMM Environmental Conditions

Influential Factors • Temperature fluctuations / sun radiation / draught air Example: Only 1 degree of temperature difference in the granite traverse creates a measuring error of 12 (twelve) µm/m, if you measure at a distance of 600 mm from the X measure, • i. e. on the table surface of CMM. Scanning / individual points: • Basically, the following applies: The more measuring points that are picked up, the safer and more expressive the result! • Here, take into consideration the correct use of shaft and outlier filters. Material – test workpiece: • The temperature of the test workpiece has a decisive influence on the measuring result. • The test workpieces must generally be "acclimated" prior to measuring, i. e. they must be stabilized to the ambient temperature of the CMM. • Bascially, a capturing and calculation of the workpiece temperature must take place by means of the temperature stylus or the temperature sensors on the CMM in order to achieve a correct measurement result. • Projections • Avoid short measuring lengths with simultaneous large evaluation length. I. e. projections with a multiple of the measuring length. Example Measuring Requirement: Coaxiality of two symmetric cylinders with a measuring length of 20 mm with an axial distance of 100 mm.

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7.6.6 Inaccuracy Analysis The contributions to the measuring inaccuracies for a CMM consist mainly of the following • the known systematic deviations (21 deviation components including probing variances), which can basically be corrected • the arbitrary influences, recognizable in the arbitrary probing variances, which are caused by interpolation errors, dynamic influences and hysteresis effects. • the unknown systematic deviations, e. g. by uncorrected temperature influences, qualification inaccuracies of the used CMMs, short periodic portions of the deviation components, simplification of the mathematical models to overlay the different inaccuracy contributions. The detected inaccuracy contributions for a coordinate measuring process are shown in Fig. 1. Determining the Inaccuracy Influences Significant inaccuracy contributions of a coordinate measuring process result from the probing procedure, the machine geometry and the stability of the CMM due to temperature effects. To determine the probing inaccuracy (P), a qualified sphere and a qualified gauge ring (CMM check) are measured. To determine a length measuring inaccuracy (E) (geometry), a bore pattern (portal check) is measured in several locations on the CMM.

Measuring the deviation components of a CMM with a bore pattern

Literature Reference: "Genau messen mit Koordinatenmessgeräten", H.-G. Pressel, expert-verlag

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8: Measuring methods, part 2

8.1

Scanning with unknown contour..................................................................... 162

8.2

Scanning with 2 styli....................................................................................... 163

8.3

Point masking in open scanning paths............................................................ 165

8.4

Self-centering probing..................................................................................... 166

8.5

Safety cube...................................................................................................... 168

8.6 Park position................................................................................................... 171 8.7 Missing bore.................................................................................................... 172

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8.1 Scanning with unknown contour Features (besides points, 2D line and plane) have the "unknown contour" strategy. Here, there will be a starting point and an endpoint, just like with curve measurement. The machine tries to measure the shortest path between the starting point and the endpoint. A typical example for this scanning method is the slot.

Exercise: Clamp a workpiece with an slot and align the workpiece. Take a new slot from the toolbox and open the strategy. Click on the unknown contour, open it and probe the starting point and the endpoint. These points can be identical. Set the speed and the step distance to sensible values. Indicate a space axis, here, the normal direction of the slot. The end criterion sphere means that the end the contour was recognized as soon as the stylus "arrives" in a "sphere" with a 5 mm radius.

To run this unknown contour, in the strategy, click on "Execute now" with the right mouse button Now, the slot will be scanned.

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8.2 Scanning with 2 styli If it is not possible to scan a circular path on a workpiece with just one stylus (e.g. full circle on cam shaft), this function will allow you to measure partial circle paths with different styli at the "same" height and to combine them into one circular path. This will create a correct roundness plot.

Exercise: Align the exercise cube so it "sits on its head".

Measure two circle section with different styli on the cylinder at three heights. Apply correct styli and angle names.

There will be 6 circle sections.

Group two circle sections with the marked group.

Start the run and optimize the drive behaviour so that the end of a path is located on the same side as the start of the next path.

Create a roundness plot for every path.

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The following conditions must be observed: 1. Applicable to: Cylinder, cone, circle and circle on cone. 2. Strategies besides "circle section" will not be considered. 3. In order dissolve a group, all its elements must be marked. Actuating the button "Group circle sections" dissolves the grouping. 4. The summary of the selected circle paths takes place directly after the measurement and is switched in front of the actual evaluations. 5. The path angle of the circle paths to be combined is arbitrary. 6. The number of the circle paths to be combined is arbitrary. 7. The respective rotation direction of the circle paths to be combined is arbitrary. The rotation direction of the combined circle path is the same as the rotation direction of the first circle path. 8. The sequence of the circle paths to be combined is arbitrary. 9. The circle paths to be combined can be overlapped or feature gaps. Overlaps are removed.

A selection of the possibilities is shown in the illustration.

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8.3 Point masking in open scanning paths This function masks points at the start and the end of the scanning path. The number of points is controlled via the time factor seconds, as mainly the oscillations of the measuring system are to be eliminated.

In the measuring feature editor, the activation of the function for the entire measurement plan and for individual measuring features can be set up. • The point masking works for the following scanning paths (not with individual point measurements): • Circle cross cut of circles, cylinders, cones, spheres, if the total angle area is smaller than or equal to 360° • Circle cross cut of circles, cylinders, cones, spheres, if the total angle area is smaller than or equal to 360° • Helix of circles, cylinders, cones • VAST helix of cylinders • Grid (lines and meanders) of planes • Polylines of planes • Circle on plane of planes, if the total scanned angle area is smaller than or equal to 360°. • Line of 2D line • Unknown contour of circles, cylinders, cones, spheres, ellipses, slots, rectangles, 2D and 3D curves • Curve segments of 2D and 3D curves Notes about the settings: Standard: Start 0.25 sec; end 0 sec Short: Start 0.1 sec; end 0 sec Long: Start 0.4 sec; end 0,25 sec

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8.4 Self-centering probing Self-centering recording of an unknown contour, i.e. a slot. The functionality can be used on points, lines, circle paths (with and without rotary table), curves (with and without rotary table). The entries for the measuring force and for the self-centering probing must be made directly for one feature. An entry from a superior feature (suggestion) is not permitted. The self-centering probing can only be adjusted for strategies. This can take place in several ways. With "Resources - self-centering probing" for the recently selected feature or directly in the feature via "strategy".

The dialog box opens; with circle paths, the field "Force direction" is displayed in the window as well. For this, the respective direction must be selected.

Notes: • In the measuring feature list, features are marked with selfcentering probing/scanning by receiving an orange border. • Setting possibilities in the element editor (ON, OFF, Edit). The strategy can be edited with "edit". • With strategies with vectorial probings, the vectorial probing must be adapted with circular pitch. • Probing points can only be measured with individual points. Lines and circle paths, on the other hand, can be scanned only and without tangential probing (homing) (VAST Navigator). • With circle paths with rotary table (also for curves), the circle path must be situated rotationally symmetrical to the rotary table axis. • In general, self-centering measurements can only take place within certain limits.Hence, right angles cannot be recorded self-centering. Curves should feature a rotation direction, similar to a circle path. VAST XXT and self-centering: A self-centering probing is not allowed here, as momentum created by friction forces leads to inaccurate measurements.

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© Carl Zeiss 3D Metrology Services Exercise: On the exercise cube, the slot is to be scanned on top in a 60° area. This can take place via self-centering. Prepare a plan where the circle section exists as a strategy.

Now set the adjustments for the self-centering probing in the strategy window as follows:

Another example for self-centering: On a toothed wheel, the gaps between the teeth are to be probed via self-centering and circular pitch. Note: The force direction orients itself by the feature coordinate system. E.g., with points, the force is only switched in Fz and against the vector direction.

The measuring force The measuring force can only be assigned to features.Use all measuring strategies belonging to the feature when this force is measured. In order to assign a measuring force to one or more features, it is selected and the menu Resources -> measuring force is activated. The above dialog window is displayed, where you can enter the desired force.

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8.5 Safety cube General information The safety cube can be aligned as per a arbitrary coordinate system (also machine system MS). With workpieces, where the base alignment is very slanted, the safety cube will be slanted as well. If the majority of the features is not aligned with the base alignment or the MS, this may lead to problems with the drive paths.

Safety cubes with selectable coordinate system The safety cube can be selected according to a arbitrary coordinate system from this measurement plan.

Safety cubes with different coordinate systems Safety cube aligned with base alignment The drive paths of the stylus run along the safety cube; here, at an angle to the machine axes.

Safety cube aligned on the device system The drive paths of the styli run along the machine axes. Note: If the base alignment changes, the safety cube is "not taken along"!

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© Carl Zeiss 3D Metrology Services Exterior safety cube • During the measurement run, the following should be avoided: • a collision with other workpieces, • a collision with the stylus change rack, • driving into the end position.

For this, an exterior safety cube can be helpful. The size can be the measuring volume of the machine. If it is selected smaller, other workpieces are outside this cube. The definition takes place via: Plan - navigation - outer clearance

Switching on the drive test: Here, there are more possibilities: Plan - navigation - correction needed

The drive behavior of the machine changes as follows: • Style change rack Automatic consideration including the stylus system in the rack. The stylus that protrudes furthest into the measuring range of each rack determines a plane on which the drive path is checked. The foremost stylus tips of the rack are shown as points. • Measuring range limits (end positions): Consideration of the values from the configuration in the workroom. Drive behavior: With every generated drive path between the measuring features, there is a test for collision/end position with all defined obstacles. If a collision/end position is detected, the next one will be "tried" and so forth. With long narrow stylus systems, you will drive by the workpiece along its side, with flat wide styli only on top.

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© Carl Zeiss 3D Metrology Services Block edges Individual edges of the safety cube can be blocked. The circled edges refer to the machine table. This can change depending on the axis position! Retrieval: Plan - navigation - block edges

Exercise: Place the safety cube far to the side on the machine and define an exterior safety cube.

Test the run while considering: • End positions • Exterior safety cube • Stylus change locations • Blocked edges

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8.6 Park position General information A park position is a defined position of the stylus at the end of the CNC run.

Retrieving a park position Plan - navigation - CNC end park position

An icon can be retrieved via the function "List drive paths" in the same menu.

A path to this position can be programmed into the park position. Furthermore, a relative positioning to the master probe and stylus change is possible.

The following illustrations show a park position after the cylinder measurement in front 100 mm above the workpiece. Note: What often makes sense is the use of a safety position with the correct safety plane directly before the drive command to a position. Note: Park position will not work with measurement plans that only contain characteristics of the type "Qualifying the stylus system".

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8.7 Missing bore General information To prevent a CNC run from terminating if a bore is missing from the workpiece, the function "Missing bore" can ensure continuous operation. Retrieval: • Only with circles: via "Projection" in the features window • Further features: Measuring feature editor

Function: The bores are driven from a certain height at search speed. If there is no bore, the system drives to the next feature at this height. This height is the clearance distance: The clearance distance is the distance from the circle in the initial start direction. If the bore is not found, Calypso will drive to the next feature at this height (here, circle 2). This means that the search distance must be greater than the submersion depth of the material. Note: If the safety distance is too short to drive free of the workpiece, there is a risk of collision. If the function is preset in the measuring feature editor, Calypso will check the distance and may issue a collision warning.

Task: Measure two bores as a circle on a cube. The first bore is to be missing during the test run. For the first circle, the function "missing bore" is activated. The clearance distance is 10 mm; this may be enough to drive safely above the workpiece to the second bore. In the CNC run, place a coin over the first bore to test the function.

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Calypso Training Materials Printed in Germany Subject to modifications of the layout and scope of delivery as well as technical developments © Carl Zeiss 3D Metrology Services GmbH. © Concept, text and design: © Carl Zeiss 3D Metrology Services

© Carl Zeiss 3D Metrology Services GmbH. Heinrich-Rieger-Str. 1 73430 Aalen, Germany Phone: +49 (73 61) 5 59-1800 Fax: +49 (73 61) 5 59-1899 e-mail: [email protected] http://www.zeiss3d.de