pdms inplant stl

8/11/2019 pdms inplant stl

1/35

imps111/man1/doc1issue 070601

PDMS ImPLANT-STLversion 1.1

User Guide


2/35


3/35

PDMS ImPLANT-STL Version 1.1User Guide

i

Contents

1 Introducing ImPLANT-STL

1.1 General............................................................................................................... 1-11.2 Input to ImPLANT-STL .................................................................................... 1-11.3 Output from ImPLANT-STL ............................................................................. 1-11.4 Compatibility with PDMS DESIGN.................................................................. 1-2

1.4.1 Solid Polyhedron Definition .................................................................1-2

2 Controlling the Process

2.1 The Translation Process .................................................................................... 2-12.2 Controlling the Quantity of STL Data .............................................................. 2-22.3 Controlling the Quality of STL Data................................................................. 2-32.4 Controlling the PDMS Model ............................................................................ 2-32.5 Reviewing and Improving the PDMS Model..................................................... 2-42.6 Typical STL Files and Resultant PDMS Models .............................................. 2-5

3 Using ImPLANT-STL

3.1 Modes of Operation............................................................................................ 3-1

3.2 The ImPLANT-STL User Interface................................................................... 3-13.2.1 Advanced Options without Solid Polyhedra Option............................3-33.2.2 Advanced Options with Solid Polyhedra Option .................................3-5

3.3 Interactive Mode................................................................................................ 3-73.4 Batch Mode ........................................................................................................ 3-73.5 Adding the PDMS Macro File to PDMS DESIGN ............................................ 3-9

4 STL Input

4.1 Mechanical CAD Systems and STL File Production ........................................ 4-14.2 Units and Scalar Factors................................................................................... 4-2

5 PDMS Macro Output

5.1 General............................................................................................................... 5-15.2 PDMS Data Structure ....................................................................................... 5-1

5.2.1 PDMS v11.2 Geometry Hierarchy........................................................5-15.2.2 PDMS Version With Solid Polyhedra Geometry Hierarchy................5-2

6 Reports

7 Error Messages

7.1 System Errors .................................................................................................... 7-17.2 Licensing Errors ................................................................................................ 7-17.3 Parameter Setting Errors.................................................................................. 7-1

7.4 File Access Errors .............................................................................................. 7-2


4/35

ii

7.5 Data Errors ........................................................................................................7-27.6 Data Processing Errors...................................................................................... 7-2

8 Limitations


5/35

PDMS ImPLANT-STL Version 1.1 1-1User Guide

1 Introducing ImPLANT-STL

STL format provides an approximation of a curved surface model, with accuracy andlevel of detail cont rolled th rough a tolerance setting. PDMS ImPLANT-STL maps thisformat onto PDMS 3D primitives. Hence a 100% accurate translation of the sourcemodel in to PDMS geometry cannot be guaranteed.

1.1 General

ImPLANT-STL is a standalone program for translating stereolithography (STL)files, that have been generated from non-Cadcentre Mechanical CAD systems,into PDMS macro files that can be input to PDMS.

ImPLANT-STL is available for Windows NT platforms running WindowsNTv4.0 Service Pack 5 and Windows 2000.

ImPLANT-STL is sitefile protected, ie before you can use ImPLANT-STL itmust have been installed and tested in accordance with the instructionscontained in the PDMS ImPLANT-STL Installation Guide.

1.2 Input to ImPLANT-STL

The input to ImPLANT-STL consists of STL files generated from/by non-Cadcentre Mechanical CAD systems. Some non-Cadcentre Mechanical CADsystems have an inbuilt facility for generating STL files, others do not, and thegeneration of STL files from these systems involves the use of a separatetranslator program, such as CADfix from FEGS.

The STL files will have the extension .stland can be either ASCII or binary informat. ImPLANT-STL reads both ASCII and binary STL files.

The ImPLANT-STL program works in read-only mode and the original STLfiles will not be changed in any way.

1.3 Output from ImPLANT-STL

The output from ImPLANT-STL consists of an ASCII format macro file that issuitable for input to PDMS DESIGN. The format of the output file means thatthe program does not create any databases within PDMS DESIGN.


6/35

Introducing ImPLANT-STL

1-2 PDMS ImPLANT-STL Version 1.1User Guide

1.4 Compatibil ity with PDMS DESIGN

The files generated by ImPLANT-STL are compatible with all versions of PDMSDESIGN from 11.2 upwards. PDMS DESIGN does not need to be installed onthe machine running ImPLANT-STL.

In future PDMS releases after version 11.3.1 a new PDMS primitive has beenintroduced called Solid Polyhedron with a generic type of POLYHE. ImPLANT-STL allows the creation and use of this primitive, see theInstallation Guide.

Notethat if you use this facility to create Solid Polyhedra and you attempt toread the macro generated into a version of PDMS DESIGN that does notsupport solid polyhedra the macro will fail.

1.4.1 Solid Polyhedron Definit ion

The definition of the Solid Polyhedron is a set of faces that have to make acomplete solid, ie all edges of the faces have to have corresponding edges fromother faces. The Solid Polyhedron has the following characteristics:

1. It is more economical to store in PDMS databases than a correspondingPOHE/POGO arrangement.

2. It is faster to manipulate in the Design module.

3. The clash detection is better than POHE/POGO because it can detect partsthat are completely inside the polyhedron.

4. It allows the use of invisible edges. This is a facility that:

a. Edges are not displayed in wireline mode in DESIGN.

b. In colour-shaded mode in DESIGN the parts are displayed with smoothshading between faces that share invisible edges.

c. Drawings produced using the DRAFT module show the visible edges andany silhouette edges only.


7/35


2 Controlling the Process

2.1 The Translation Process

Within the STL format all objects are represented by triangles, the trianglebeing the shape with the minimum number of sides that can be used torepresent a three-dimensional object. Unfortunately, reducing a shape to

triangles increases the quantity of electronic data necessary to define the shape.For example, a square drawn in a CAD system is defined by its four corners orvertices. The same square in STL format is represented by two triangles, eachtriangle having three vertices, totalling six vertices, representing a 50%increase in data needed to define the square.

Figure 2-1Data Volume Comparison

Taking this analogy a step further, a cube within a CAD system is defined by itseight vertices. The surface of the same cube in STL format is represented by 12triangles, two for each of the six faces of the cube, each triangle having threevertices, totalling 36 vertices. This represents a 450% increase in data needed todefine the cube.


8/35

Controlling the Process


Shapes within a CAD system more complex than a cube result in even greaterdata increase factors. It can therefore be seen that STL files can be very large in

terms of data volume or file size. This has two main effects:

Large STL files may take several hours to map into PDMS DESIGN.

Highly detailed models in PDMS may drag down the performance of thecomputer and will be slow to manipulate.

It is therefore very important that the detail in the source CAD file

used to generate the STL file and the amount of detail that is required

in the PDMS Model should be considered very carefully.

However, it is impossible to give any definite instructions as to what should bedone as there are too many possible combinations of source CAD systems and

PDMS model uses to define parameters for. The most suitable combination ofparameters and settings is best determined by trial and error. The followingguidelines may be useful:

control the quantity of STL data

control the quality of STL data

control the PDMS model

review and improve the PDMS model.

2.2 Controlling the Quanti ty of STL Data

ImPLANT-STL processes STL data intelligently, attempting to recognisegroups of triangular facets that equate to particular standard shapes defined inPDMS as PDMS primitives (box/cylinder/pyramid/extrusions and negativeversions of these). Facet data that cannot be mapped to any of these PDMSprimitives is dealt with by creating the facets as POHE (polyhedron) primitives,a less efficient form of handling the data. However, if the solid polyhedronmode is used (see below), and ImPLANT-STL recognises a solid then this isefficient.

A good indicator of a successful operation using ImPLANT-STL is the quantity

of POHE primitives within the resultant PDMS model. The fewer the number ofPOHEs the easier it is to manipulate the data in PDMS DESIGN and PDMSDRAFT.

There are therefore two factors that directly affect the performance of modelmanipulation in PDMS DESIGN. These are:

The ability of ImPLANT-STL to recognise and map triangular facetgroups to PDMS primitives.

The quantity of data to be translated.

It is a good working practice to minimise the amount of data that needs to be

translated; this can be done by applying the following guidelines:


9/35

Using ImPLANT-STL


Remove all non-essential aspects of the source model, eg in the case of agearbox, export the gearbox casing but not the gearbox internals.

Remove or disable features in the originating Mechanical CAD Systemthat automatically generate many curved surfaces, such as fillets andchamfers. Some Mechanical CAD Systems allow these features to bedisabled temporarily, while the export to STL file operation is in progress.

Use an appropriate tolerance setting when exporting to the STL file. It isimpossible to stipulate an exact tolerance setting since this depends verymuch upon your requirements for the PDMS DESIGN model. The higherthe tolerance factor setting the less accurate will be the resultant modeland vice versa. The recommended approach is to start with a hightolerance setting, inspect the resultant PDMS model, and re-import all or

part of the model at a lower tolerance setting, as necessary.

2.3 Controll ing the Quality of STL Data

The integrity of the source model has a direct bearing on the quality of the dataproduced during an STL export operation. For example, if a solid in the originalmodel is not properly closed prior to being exported, then ImPLANT-STL willnot recognise the resultant triangular facet group as a single PDMS primitiveand will map the solid inefficiently with POHE primitives. Most MechanicalCAD Systems have a healing facility that will process the model and check it for

inconsistencies such as solids that are not properly closed. It is thereforestrongly recommended that source models are healed in their originatingMechanical CAD System prior to the data being exported in STL format. Wherethe Mechanical CAD System does not have this facility, another applicationsuch as CADfix from FEGS may be used to provide the healing function and tocarry out the export to STL format.

The STL format is an approximation of a curved surface model, the accuracyand level of detail of which may be controlled through tolerance setting. Abalance must be struck between too great and too low tolerance settings. Thiscan be done by reviewing and where necessary improving the PDMS modelcreated.

Too great a tolerance setting may result in errors in the STL file.

Too low a tolerance setting may result in the STL translation operationfailing, eg where holes are located close to the edge of a solid.

2.4 Controlling the PDMS Model

If you are aware that holes below a certain diameter need not be transferred tothe PDMS model, then the option to remove these holes should be selected. This

may enable ImPLANT-STL to recognise and map more parts to PDMS


10/35



primitives, making it easier to manipulate the PDMS model. There may beoccasions however when ImPLANT-STL cannot remove the holes in a part

because in doing so it would invalidate the part.

You can obtain the value of the minimum hole size that has been exported byviewing the ImPLANT-STL report. You can then use a higher value than this toremove these holes and re-run the export operation through ImPLANT-STL toreview the changes this makes to the model.

The Wrapperoption should be used only when you are sure that most or allsolid parts are inside other parts and can therefore be removed withoutaffecting the appearance of the PDMS model. If the Wrapperoption is usedwhen this is not the case, then the resultant PDMS model may be too difficult tomanipulate. This is due to the fact that Wrapping prevents any PDMS

primitive recognition, increasing the amount of data that has to be transferred.

2.5 Reviewing and Improving the PDMS Model

The extent to which the resultant imported PDMS model may require to bemodified depends entirely upon your end requirements. A crude representationmay be sufficient for space management or clash checking purposes, whereas ahighly detailed model is required for realistic visualisation. Alternatively, if theintention is to actively work on and manipulate the imported data, then anefficient and compact data structure is of paramount importance. Whatever the

intention it is best to review the PDMS model. The review can range from asuperficial visual check to a detailed scrutiny of the graphics and databasehierarchy.

Reviewing the PDMS model allows you to:

verify that the level of detail in the model is sufficient for your purposes

identify areas where the data structure could be improved

identify any problem areas.

If the PDMS model is generated through ImPLANT-STL with a high tolerancesetting, the model needs to be checked visually to locate errors due to failings in

the STL export process. Identified problem areas can then be re-exported at alower tolerance setting. If this does not correct the errors or there is geometrymissing from the model, then there may be faults with the source model. In thiscase check that the source model has been healed prior to export.

If the PDMS model is visually acceptable but is slow to manipulate it should bechecked to see if there are any areas where geometry can be remodelled moreefficiently using fewer primitives. Viewing the model in wireline mode willeffectively display areas that are densely packed with POHE primitives, ieareas where it has not been possible for ImPLANT-STL to generate a moreefficient representation based on PDMS primitives.


11/35

Using ImPLANT-STL


2.6 Typical STL Files and Resultant PDMS Models

The following Figures are examples of typical STL files and the PDMS modelsresulting from their import into PDMS with various option changes inImPLANT-STL.

Figures 2-2 to 2-5 are examples of a PDMS model generated from aPro/ENGINEER source file.

Figure 2-2 Original Model as Triangles

Figure 2-3Solid Model with All Holes Translated


12/35



Figure 2-4Solid Model with Holes Smaller than 40 mm Diameter Removed

Figure 2-5 Solid Model with All Holes Removed


13/35

Using ImPLANT-STL


Figures 2-6 to 2-8 are examples of a PDMS Model generated from a CATIAsource file.

Figure 2-6 Original Model as Triangles

Figure 2-7 Solid Model with All Holes Translated


14/35



Figure 2-8 Solid Model with All Holes Removed


15/35


3 Using ImPLANT-STL

3.1 Modes of Operation

ImPLANT-STL has two modes of operation:

interactive mode

batch mode.

In the interactive mode you input your requirements to the ImPLANT-STLprogram via the user interface.

In the batch mode you inputs your requirements to the ImPLANT-STL programvia a batch (.bat) file.

The normal mode of operation is the interactive mode.

3.2 The ImPLANT-STL User Interface

The ImPLANT-STL user interface comprises two interactive Windows-baseddialog boxes, the second accessed from the first. The basic dialog box is shownin Figure 3-1. and comprises the following sections/fields and buttons:

STL Filesection

File name this field is used to specify the full path andfilename of the STL file to be translated.

STL Mode this field is used to specify the format of theSTL file, ASCII or Binary. ASCII is the defaultvalue of this field.

PDMS Macro Filesection

File name this field is used to specify the full path andfilename of the resultant PDMS macro file. If novalue is entered here the program defaults themacro file to the same location as the sourceSTL file and gives it the same name as thesource STL file with the extension amended to.mac.


16/35

Using ImPLANT-STL


Reportingsection

File name this field is used to specify the full path andfilename of the ImPLANT-STL program log fileor report. If no value is entered here theprogram defaults the log file to the samelocation as the source STL file and gives it thesame name as the source STL file with theextension amended to .log.

The STL File, PDMS Macro Fileand Reportingsections also contain a browser

button ( ). This is to enable you to browse and select file locations andnames. This may be a simpler way to specify a particular location and filenamewhere the full path and filename is a complex string.

PDMS ModelSection

Holes this field is used to set how the ImPLANT-STLprogram deals with holes. The options are:

On the default value for this field. Where theprogram finds holes in objects in the STL file,corresponding negative primitives (holes) aregenerated in the MAC file.

Off when this option is selected, where the programfinds holes in objects in the STL file, these areall ignored and no holes are generated in theMAC file.

Diameter> when this option is selected, you are able tospecify the maximum size of hole that is to betranslated as a hole. Where the program findsholes in objects in the STL file with a diametersmaller than the value entered, these areignored and corresponding holes are notgenerated in the MAC file. Where the programfinds holes in objects in the STL file with adiameter equal to or greater than the value

entered, corresponding holes are generated inthe MAC file.

Scale factor this field is used to specify an enlargement orreduction factor that the ImPLANT-STLprogram is to apply. The default value for thisfield is 1.0.

Note: Within the ImPLANT-STL program there is no concept ofunits. During the translation process the ImPLANT-STLprogram maintains the physical relationships of objects in theSTL file, resultant primitives in the MAC file are therefore ofthe same relative size. If the units used in the originating

program, from which the STL file was generated, are known,


17/35


the Scale factorfield can be used to scale up or down theresultant MAC file objects to suit the PDMS file units.

Advanced Opt ions>> clicking on this button calls up the advanceddialog box, shown in Figure 3-2 or 3-3.

Figure 3-1 ImPLANT STL User Interface - Basic Dialog Box

3.2.1 Advanced Options without Solid Polyhedra Option

The second dialog box is similar to the first dialog box, with the following

additional fields and button in the PDMS Modelsection:Min. sides per cylinder this field is used to specify the minimum

number of sides required in order for theprogram to recognise and map a cylinder. Theprogram determines that an object is acylinder by inference, it actually detects acylinder as an extrusion having a circularprofile. The circular profile is mapped byintersecting vertices, and the value set in thisfield represents the minimum number ofintersecting vertices that the program is

required to use to map a circular profile.


18/35

Using ImPLANT-STL


Geometry this field is used to set how the ImPLANT-STL program is to deal with coplanar faces.

The options are:

Compressed the default value for this field. With thisoption selected the program combinescoplanar faces with shared edges into biggerfaces. It also maps geometric solids intoPDMS primitives. This option produces thesmallest resultant MAC file.

Uncompressed with this option selected the program does notcombine coplanar faces with shared edgesinto bigger faces and does not map geometric

solids into PDMS primitives. This optionproduces a much larger MAC file than theCompressedoption.

Wrapper this field is used to set how the program is totreat objects with internal parts. The optionsare:

On with this option selected the program creates awrapper around all solid parts. It will thenremove from the MAC file any parts that arewholly inside other parts. Internal featurescreated by solid parts overlapping are alsoremoved from the MAC file. This option isuseful if the STL file contains parts that havelots of internal parts that can be recognised byImPLANT-STL as solids.

Off the default value for this field. With this optionselected the program does not perform thewrapping operation.

Advanced Opt ions


19/35


Figure 3-2 ImPLANT-STL User Interface-Advanced Dialog Box

3.2.2 Advanced Options with Solid Polyhedra Option

Note that to be able to use this option the Environment VariableIMPLANTSTLPOLYHE has to be set to trueas described in theInstallationGuide.

The following additional fields are present on the Advanced dialog box.

Solid polyhedron This field is used to set how the program is to

map solid parts to PDMS. The options are:On With this option selected the program creates

solid polyhedra for solid parts that can not bemapped onto Boxes, Cylinders and other PDMSprimitives. This is the default value when theappropriate environment variable has been setto true.

Off With this option selected the program does notcreate solid polyhedra but maps these parts toPDMS POHE/POGO.


20/35

Using ImPLANT-STL


Edge visibility This field is used to set the mode by which theprogram can set edges to be visible or invisible.

The options are:

On The default value for this field. With this optionselected the program sets all edges to be visible.

Off With this option selected the program sets alledges to be invisible.

Angle > With this option selected you can set an angleby which the program computes if an edge willbecome visible or invisible. The default value isset to 60 degrees. If the angle is greater thanthe angle between the normals of the two faces

that share an edge then the edge becomesinvisible otherwise it will become visible.

Figure 3-3 ImPLANT-STL User Interface-Advanced Dialog Box (SolidPolyhedra option)


21/35


3.3 Interactive Mode

The following procedure represents the minimum interaction that is required inorder to generate a PDMS macro file from an STL file.

STEP 1 Start up the ImPLANT-STL program by executing the following:

Start>Programs>CADCENTRE>PDMSImPLANT-STL 1.1.1>PDMSImPLANT-STL

STEP 2 Enter or select, using the browser, the name of the STL file to betranslated.

STEP 3 Specify whether the STL file is in ASCII or binary format.

STEP 4 Click on the Createbutton to start the translation process.STEP 5 Repeat STEPS 2 to 4 for each STL file that is to be translated.

Click the Exitbutton to terminate the ImPLANT-STL program.

The above procedure will create one or more PDMS macro files suitable forinput to PDMS DESIGN. Each of the macro files will by default have the sameroot name as the associated originating STL file, with the extension of .mac.

In addition, there will be also be a report file (log) created for each translationfile operation. Each of the report files will by default have the same root nameas the associated originating STL file, with the extension of .log.

All file names are validated by the ImPLANT-STL program prior to the

translation operation starting. You can rename PDMS macro files and reportfiles using Windows NT Explorer.

3.4 Batch Mode

ImPLANT-STL may be run from a batch file, allowing multiple STL files to betranslated into PDMS macro files in the background.

In order to run ImPLANT-STL from a batch file it is first necessary to create abatch (.bat) file containing the instructions to initiate the ImPLANT-STL

program and also the options to apply to the program. The options available areas previously described in Chapter 2.2 The ImPLANT-STL User Interface.

The format of the batch file is shown below:

ImPLANTSTL [-b] [-o][-r][-w] [-t] [-h][-c] [-s] [-dpdms113] [-i] [-?]

where:

is the filename of the input STL file. (Filename

must notcontain spaces.)


22/35

Using ImPLANT-STL


is the filename of the resultant PDMS macro file,the default being the same root as the input STL

file with the extension .mac. (Filename mustnotcontain spaces.)

is the filename of the report or log generated bythe program, the default being the same root asthe input STL file with the extension .log.

is a numerical value indicating to the programthe minimum diameter of hole that is to bemaintained during the translation process, ieholes with a diameter of less than the valuespecified will be ignored. If this value is set to -

1.0 then all holes will be ignored.is a numerical value indicating to the program

the minimum number of sides that to be used torepresent a cylinder or negative cylinder. Thedefault value is 6.

is a numerical value indicating to the programthe scalar factor that is to be applied during thetranslation in order to make the resultant modelbigger or smaller.

Is an angle in degrees for the program to decide

which edges are to become invisible when a SolidPolyhedron is created. If the angle given isgreater than the angle between the normals ofthe two faces that share the edge then the edgebecomes invisible, otherwise it will becomevisible.

The options to be applied are included in the batch file in the form of command lineswitches, where:

-b indicates that the input STL file is a binary file.

If this switch is not used the program uses thedefault value, in this case ASCII.

-o indicates that the following filename is to be usedfor the output MAC file. If this switch is not usedthe program uses the default value.

-r indicates that the following filename is to be usedfor the report file. If this switch is not used theprogram uses the default value.

-w indicates that the Wrapperoption is to be used. Ifthis switch is not used the program does not

apply the Wrapper.


23/35


-t indicates that the Geometry option is to be set toUncompressed. If this switch is not used the

program will use the default value, Compressed.-h indicates that holes are to be translated and that

the following numerical value is to be applied asthe minimum size of hole that is to be translated.

-c indicates the minimum number of sides to beused to recognise and map cylinders or negativecylinders.

-s indicates that the following figure is to be appliedduring the translation in order to enlarge orreduce the resultant model in the MAC file.

-dpdms113 indicates that solid polyhedra are to be created.

-i indicates that the following figure is to be appliedto decide if an edge is visible or invisible.

-? Help

Several STL input files may be processed at once if you create a batch file witha series of ImPLANT-STL commands.

3.5 Adding the PDMS Macro File to PDMS DESIGN

The output from ImPLANT-STL is a PDMS macro file, ready to be read intoPDMS DESIGN. This is done using the following procedure:

STEP 1 Start up PDMS DESIGN and make sure that the database is atthe appropriate ZONE level.

STEP 2 Read in each MAC file as:

$m

Large MAC files should be read into PDMS DESIGN by entering PDMSDESIGN in dev tty mode and entering the command trace off before the read

command.Reading in the macro may take some time, especially with large files.


24/35

Using ImPLANT-STL



25/35

PDMS Macro Output


4 STL Input

4.1 Mechanical CAD Systems and STL File Production

ImPLANT-STL addresses the problem of transferring 3D model data fromMechanical CAD Systems to PDMS, where the model can be manipulated moreeasily in the Design module and drawings can be produced via the Draftmodule. The most popular Mechanical CAD Systems are:

CATIAPro/ENGINEERI-DEASSolidWorksACIS based systemsParasolid based systemsUnigraphicsSolid EdgeCADAMROBCADCADDS5.

The output files from other popular Mechanical CAD Systems, such asAutoCAD and Microstation, may be imported into PDMS DESIGN usingproduct specific translators.

Most of these Mechanical CAD Systems have the capability to export files in theSTL format direct or some other standard format or CAD native format such asIGES, STEP AP203/AP214, etc. Translator programs are available which canread these other export file formats and generate STL files. One suchTranslator Program is CADfix from FEGS. The possible routes to generatingSTL files are shown in below.

Figure 4-1 STL File Input to ImPLANT-STL


26/35

STL Input


The method of production of the STL files is an important factor in minimisingthe volume of data that needs to be transferred. Applying the following factors

will help to reduce the volume of data:

All curved parts are approximated as planar faces (triangles) in theprocess of being exported to the STL file. All STL translator programsoffer an approximation/tolerance factor to achieve this. It is veryimportant to control the number of triangles produced, keeping these tothe minimum to produce an acceptable model in PDMS DESIGN.

All parts of the model that are not essential should be excluded from thetransfer, in particular any internal parts that will not be used in PDMS.

Many features, such as chamfers, are not needed in PDMS and these alsoshould be excluded from the transfer.

4.2 Units and Scalar Factors

Within STL there is no concept of units and therefore ImPLANT-STL generatesPDMS macro files with no reference to any units. The translation operationmaintains the physical size of parts as they were in the originating program.

The size of the parts as they appear in PDMS can be adjusted by applying ascalar factor to the STL file within ImPLANT-STL.


27/35

PDMS Macro Output


5 PDMS Macro Output

5.1 General

The data output from ImPLANT-STL is presented in the form of a PDMS macrofile that can be read into PDMS DESIGN in order to create the correspondingprimitives and associated hierarchy.

5.2 PDMS Data Structure

When an STL file is translated into a MAC file and this is read into PDMS, allgeometric parts are converted to PDMS primitives which form a single PDMSEQUIPMENT per STL file. PDMS uses the name from the MAC file as theEQUIPMENT name.

5.2.1 PDMS v11.2 Geometry Hierarchy

If a BOX, PYRAMID, CYLINDER or EXTRUSION is recognised by ImPLANT-STL, then these primitives are added to the PDMS EQUIPMENT element.Negative primitives are added below these primitives.

Any other closed volumes that are not recognised as being any of the abovePDMS primitive types are added to the EQUIPMENT element as aSUBEQUIPMENT. Each face with one or more holes in it is represented as anEXTRUSION with each hole represented by a NEXTRUSION. All remainingfaces, with no holes, are represented by PDMS POHEs, each face of a POHEbeing represented by a single POGO (polygon) element. The POHEs are added

under the SUBEQUIPMENT.All non-closed volumes are split into non-manifold surfaces. Each non-manifoldsurface is then treated as a closed volume as detailed previously.

The geometry hierarchy is as shown in Figure 5-1.


28/35

PDMS Macro Output


Figure 5-1 PDMS Geometry Hierarchy

5.2.2 PDMS Version With Solid Polyhedra Geometry Hierarchy

Any Solid Polyhedra (POLYHE) will be created under the EQUIPMENThierarchy rather than as a set of Extrusions and POHE under aSUBEQUIPMENT.


29/35

Error Messages


6 Reports

The standard report or log generated by ImPLANT-STL following a translationoperation provides the following information:

a count of the primitives found and translated

a list of errors or warnings

An example of a report is given below:

ImPLANT-STL REPORT

Date of run: Tue May 24:11:55:29 2001

Input StereoLithography Binary file:C:\CADCENTRE\PdmsImPLANT-STL1.1.1\test\slide_gate1.stl

Output PDMS DESIGN macro file:C:\CADCENTRE\PdmsImPLANT-STL1.1.1\test\slide_gate1.mac

primitives Processed

--------------------

Number of primitives recognised is 40

Number of Solid Shells is 15

Number of Boxes is 2

Number of Extrusions is 14

Number of Cylinders is 9

The smallest hole diameter found exported is: 10


30/35

Reports



31/35

Error Messages


7 Error Messages

7.1 System Errors

These errors indicate that there is something wrong with the ImPLANT-STLprogram installation. In the first instance try re-installing the program.

Process cannot be initialised - check installationCannot find process for ImPLANT-STL user interface - checkinstallation

7.2 Licensing Errors

Either you do not have a valid license for the product, or all your licenses are inuse.

***** FATAL SITEFILE ERROR *****

Please contact your CADCENTRE Support representative

Cannot get license for this version, error =

** Warning **: PDMS ImPLANT-STL license expires in %d days

7.3 Parameter Setting Errors

The following errors may appear when operating ImPLANT-STL in InteractiveMode:

Must provide a file name for STL file input

Must provide a file name for PDMS Macro output

You have not provided a report filename

Output file has same name as STL file input

Report file has same name as STL file input

Diameter must be a value >0.0

Scalar factor must be a value >0.0

Number of cylinder sides must be an integer >=3


32/35

Error Messages


The following errors may appear when operating ImPLANT-STL in batch mode:

**Warning**: No scale factor for -s argument

**Warning**: Invalid scale factor for -s argument:

**Warning**: No argument for output file name

**Warning**: Invalid name for -o argument:

**Warning**: No argument for report file name

**Warning**: Invalid name for -r argument:

**Warning**: No number for holes diameter argument

**Warning**: Invalid number for -h argument:

**Warning**: No argument for sides in a cylinder**Warning**: Invalid number for -c argument:

**Warning**: Invalid number for -i argument:

**Warning**: Unexpected argument:

**Warning**: No Input File Name Supplied

7.4 File Access Errors

Either you have not provided a filename where it is needed, or the file cannot befound, or does not have the correct access rights set.

**Warning**: Cannot open input STL file

**Warning**: Cannot open output PDMS macro file

7.5 Data Errors

**Error**: Unexpected end of file

**Error**: This file does not start with solid: It may not be an STLASCII file

**Error**: Non-triangular facet(s) detected

**Error**: This File is incomplete (or not a binary file)

7.6 Data Processing Errors

**Warning**: Wrapper failed

**Warning**: The wrapper model did not create a solid model


33/35

Error Messages


**Warning**: Object has not been recognised as solid

**Warning**: No holes have been removed from primitive because too many faces were to be removed


34/35

Error Messages



35/35

Error Messages

8 Limitations

ImPLANT-STL is not capable of mapping all PDMS primitives, inparticular it cannot map Surfaces of Revolution due to the very highnumber of faces that it would need to generate.

Occasionally ImPLANT-STL does not recognise solid parts.

ImPLANT-STL may fail when attempting to translate surfaces thatoverlap or are duplicated for open skin surfaces.

Documents

pdms inplant stl