Catia Functional Design

Functional Design 

Student Stude nt Note Notes: s:

DS Solu Solutio tions ns Tr Train aining ing Foils

Functional Design

S E M E T S Y S T L U A S S A D t h g

Version 5 Release 18 September 2007 EDU_SOL_EN_FID_AF_V5R18



About this course Objectives of the course Upon Completion of this course you will be able to use the Functional Molded Part workbench of CATIA V5 to create Styled Plastic and Packaging molded parts.

Targeted audience AE with styling project background

Prerequisites Students attending this course should have knowledge of CATIA C ATIA V5 Fundamentals and Functional Molded Part


1 Day



Table of Contents (1/5) Methodology Guide Introduction A New Technology Practice Process FMP Benefits of Functional Modeling: An Illustration Changing Conventional Practices

Improving the Performance Performance Strategies Options and Settings Dummy Cavity / Core

Data Structure


8 9 11 12 13

14 15 16 17

19

Design Order Reminder Managing Design Specifications (Design inputs)

20 21

Functional Set Sketches: Update Cycle and Associativity in FMP Sketches: Solid Selection Possibilities for FMP Introduction to the External Shape Methodology Characteristics of the External Shape External Shape Vs Push, Pull, Fitting

22 23 24 25 26 27



Table of Contents (2/5) External Shape versus Part Design Union Trim Applying the External Shape Methodology

28 29

Part Structure and Multi-bodies Order Independence and Modifiers Functional Set and Modifiers Rerouting Fillets and Drafts

33 34 38 39

Shell Management Managing Design Specifications (Shell Properties) The Shell in Functional Modeling Solving the Shellable Feature-Error Isolated Core Vs Select Core Creating Basic Features using Surfaces Thin Part in Functional Modeling Features Defining or Impacting the Shell

Design in Context


Design in Context: Introduction Features Belonging to the Design in Context Category Envelope Body

40 41 42 45 46 47 48 50

51 52 53 54



Table of Contents (3/5) Examples of Envelope Body Using Envelope Body Methodology

55 57

Envelope Body Methodology: First Method Envelope Body Methodology: Second Method

58 62

Design for Manufacturing Design for Manufacturing: Introduction Applying Draft using Tools Walls w ith Different Drafts Generating Different Drafts Betw een Faces Walls w ith Different Drafts Betw een Faces (R16) Drafts on Faces generated by Push or External Shape Functional Draft w ith Tangent Continuity Removing Undercuts using an Envelope Body Local Thickness

Tips for Reference


Extend Internal Features Outside the Core Volume Creation From a Surface Use Joined Surface for Cut

64 65 66 68 70 71 75 76 79 80

82 83 86 87



Table of Contents (4/5) Use Up to Plane/Surface Limit or Cut Feature Parting Radius in the Draft Properties Definition

88 89

Possible Ribs Creation

91

Defining Mold Models Mold Model Example How to Extract the Core as it is in the Part Model How to Extract the Cavity as it is in the Part Model How to Define the Core and Cavity for Milling How to Define the Model for EDM Tools How to Define the Model for Fixed Inserts How to Insert the Shrinkage Simulating Results of the Models Defined for Molding

Creating and Using Powercopies


92 93 94 95 96 98 100 101 102

103

What is a Pow erCopy? Recommended Structure For a Pow erCopy

104 105

Reusing Existing Part Design Templates How to Use Pow erCopy Additional Information

106 107 109



Table of Contents (5/5) To Sum Up


112


Methodology Guide Introduction In this lesson, you will be introduced to the Functional Modeling approach.

•

Topics covered in this course: 1. Meth Method odol olog ogy y Gu Guid ide e Introduction 2. 3. 4. 5.

Improvi Impro ving ng th the e Pe Perf rfor orma manc nce e Data St Structure Shel Sh elll Ma Mana nage geme ment nt Desi De sign gn in Co Cont nte ext

6. Desi Design gn for for Man Manuf ufac actu turi ring ng 7. Ti Tips ps for for Re Refe fere renc nce e


8. Def Defin ine e Mol Mold d Mod Model els s 9. Cr Crea eati ting ng an and d Usi Using ng Powercopies




A New Technology (1/2) In Functional Modeling, the persistent behavior guarantees that the resulting geometry is always coherent with w ith the design intent, therefore enabling design changes at any moment, while reducing the possibility of errors. The interactivity is also significantly simplified. The first implementation of the Functional Modeling technology is incorporated in the Functional Molded Part Part (FMP) workbench of CATIA V5. FMP provides provides a set of high level dedicated functional features. As dedicated functional specifications are embedded in the features, the number of user interactions while designing plastic or molded parts are redu re duce ced d.


Design Intent: Rib has to be typically applied inside the shelled body

Behavior: The part of the rib that goes goe s outsid outside e the ‘Shelle ‘Shelled’ d’ body gets automatically trimmed.

User interaction Saved: Trimming of Rib sketch to the Shell.



A New Technology (2/2) FMP is new Functional Modeling extension option available from CATIA V5 R15. This extension includes functionality allowing automatic extraction of the Core, Cavity. Some functional volumes can also be extracted to change their behavior. For example, a volume used for cutout can be extracted as a solid to create the EDM tool. This integration provides molded part designers with a comprehensive solution covering the entire creation process.

Design Intent: Ribs are to be drafted by some angle to provide a relief when the component is ejected out of the mold.


Behavior: The Rib feature can apply a draft to the rib walls. This draft is intrinsic to the feature.

User interaction Saved: Manual application of draft after the creation of Rib.

Volume used to make this cutout can be directly extracted to form the Electrode for EDM



Practice Process FMP Surfaces from styling office Shell properties Draft properties Basic features: Protected, Add, External, Core (inner shape), Internal

Functional feature

Rib, Rest, Pocket, Grill,

Dress up: Fillet, Draft

Draft Analysis

Knowledge Advisor

Core & Cavity extraction

Rule, Check

Context

Push, Pull, Fit, (External shape option) S E M E T S Y S T L U A S S A D t h g

Mold Tooling Design

Conceptual Detail Mold


Benefits of Functional Modeling: An Illustration Part Design Functional Modeling (Tree structure



Changing Conventional Practices Moving from any history based system, such as Part Design (PDG), to an efficient implementation of the Functional Modeling (FMP) concepts requires a change of conventional practices and thinking, for example: Think functional and not geometrical & sequential. The designer is free to create features instead of concentrating concentrating on sequential modeling. The skeleton approach is highly recommended for FMP (as it is already for PDG). Functional Modeling is order independent. However the creation of some features will always require a logical sequence (see also Order Independent and Modifiers). Ask yourself Why you need to obtain a specific geometrical result. Use protected features instead of Pockets to remove material

Functional Modeling increases productivity: Functional Modeling should provide on average a 30% to 50% increase in productivity compared to any PDG methodology, when correctly applied. S E M E T S Y S T L U A S S A D t h g

However this performance increase cannot be obtained everywhere. Performance control is different than with PDG, due to the different dif ferent methods for computing the the geometry. Check ‘Performances’ chapter for details. details.




Improving the Performance In this lesson, you will learn some strategies for improving the performance while working on the functional designs.

•

Topics covered in this course: 1. Met etho hodo dolo logy gy Gui uide de Introduction

2. Im Impr prov ovin ing g the the Pe Perf rfor orma manc nce e


3.

Data St Stru ruc cture

4. 5. 6. 7. 8. 9.

Shelll Man Shel anag age eme ment nt Des esig ign n in Con onte text xt Desi De sign gn for for Man Manuf ufac actu turi ring ng Tip ips s for for Re Reffer eren ence ce Def efin ine e Mol Mold d Mod Model els s Cre reat atin ing g and and Usi sing ng Powercopies


Performance Strategies While working on very large models, the update time can take over one minute and decrease the productivity. Simple design strategies can maintain a reasonable update time, even if the model is complex.

The following methodologies / tips, help to increase performance: Options & Settings Dummy Shell/Cavity methods Design organization: organization: multi-bodies approach (cf. Data structure – External Shape methodology)




Options and Settings The Manual Update mode should always be used. Using Manual Update, Update, it becomes possible possible to run the update update after a series of features have been defined. As most Input/validity errors (e.g. non-closed profiles..) can be detected during the feature definition itself, it is not necessary to run run the update update to check if the inputs were correct. Manual / Auto Update icon in the Tools toolbar allows to switch swi tch the Update Option directly without wi thout going through the menu Tools/Options

Use ‘Isolated’ rather than than ‘Interconnected core’ for the shellable features (where (w here applicable): S E M E T S Y S T L U A S S A D t h g

‘Isolated core’ means only the current ‘Isolated current shellable feature is used to compute the shells, which is much faster.




Dummy Cavity / Core (1/2) The most costly features to update are usually the core and cavity c avity styling surfaces which define a complex complex shell. But a designer seldom needs to see the cavity side when designing features that only affect the core (like (li ke ribs, bosses) and vice-versa. Therefore it is very efficient to use use simpler ‘dummy’ ‘dummy’ core or cavity when concentrating on the design of exterior or interior features respectively. When working on the interior (core side): Create Crea te a new ‘Shellable ‘Shellable Featu Feature’ re’ with the same core surface but a simpler cavity side Advantages: The update time can be dramatically reduced. For an Industrial Example with approximately 60 features, update time reduces to 1/8th.

> 1min S E M E T S Y S T L U A S S A D t h g

< 15s

Comp Co mple lex x Co Core re & cav avit ity y

y t i e d v i a S C

Witth du Wi dumm mmy y ca cav vit ity y

Dummy Cavity

Original Origi nal Shell Shellable able

Update time e e r d o i C S

Complex

with dummy

Dummy Dumm y Shell Shellable able

Same core



Dummy Cavity / Core (2/2) When working on the exterior (cavity side), you can select sele ct a simple Core Surface using the Dummy Core methodology.

Dummy Core

If the core is ‘interconnected’ or ‘isolated core’, simply deactivating the ‘shell properties’ can also help us save the update time. It is almost similar to the the ‘Dummy Core’ methodology as there there would not be any shelled volume.


Deactivate Shell Properties



Data Structure In this lesson, you will learn to manage the design inputs and external exte rnal shape characteristics.

•

Topics covered in this course: 1. Met Metho hodo dolo logy gy Gu Guid ide e Introduction 2. Im Impro provi ving ng th the e Pe Perf rfor orma manc nce e

3. Data Str Structure


4. 5. 6. 7. 8. 9.

Shelll Ma Shel Mana nage geme ment nt Desi De sign gn in Co Cont nte ext Desi De sign gn for for Man Manuf ufac actu turi ring ng Tips Ti ps fo forr Re Refe fere renc nce e Deffin De ine e Mol Mold d Mod Model els s Crea Cr eati ting ng an and d Usi Using ng Powercopies



Design Order Reminder In Functional Design, you need not care about creation order of functional features. Each feature is independent. However, to clarify your design intend, you can: Reorder your features (this does not affect the end result) Regroup your features in Functional Sets.

= S E M E T S Y S T L U A S S A D t h g

=


Managing Design Specifications (Design inputs) The first step in Functional Design Design is to create a new Part. Hybrid Hybrid Mode is not not recommended as the Bodies created with Hybrid Design mode mode cannot contain any Solid Functional Set. For construction elements, you can create a Geometrical Set to group the sketches, surfaces etc of the functional features. Wireframe references like planes, axes can be kept in a different Geometrical Set.


Disable hybrid design

Construction Elements and Wireframe References



Functional Set Functional Set is a organization feature similar to geome geometri trical cal set : It defines a group of functional features It can contains functional features and also sketches, wireframe or surface features A functional set can be the ‘In Work Object’. New functional and wireframe features can be directly created in it. Features displacement between and inside functional sets is possible The Functional Set feature provides a full capability to organize and manage the specification tree in order to group features by function and to capture design intents in a better way.




Sketches: Update Cycle and Associativity in FMP Sketcher tool in CATIA is compatible with Part Part Design as well as FMP. A good practice suggests not making constructions based based on faces or edges, using Functional modeling or Part Design. However, sometime it’s unavoidable because the workaround may be too complex for getting the same type of associativity. FMP is conceptually Order Independent so reuse of feature geometry to create a new geometry should be avoided. With Part Design, you design in sequence, so it does not matter if i f you create a constraint with w ith a previous feature. With FMP, as the Features are order independent (parallel contribution), you should not use them to constraint new ones. In other words, the FMP process follows the behavior rules and not the order sequence, therefore a face or an edge might not become available for other constructions. Recommendations Use geometries / sketches based on independent references construction elements (also called Skeleton or Framework). However in FMP, some some selection on existing existing solid are allowed and can be managed easily if you limit this usage inside separated bodies. S E M E T S Y S T L U A S S A D t h g



Sketches: Solid Selection Possibilities for FMP FMP allows to create small sequences of features dependencies: Sketch support can be created on planar faces of existing function Sketch constraints can be be positioned on those type of solid solid geometry: self feature edge, self feature vertex as shown in the image below.

However, FMP Functional Functional Modeler, will detect an ‘Update Cycle’ and will display the following warning in all the other cases. cases. For example. Cross Cross edge, Cross vertex, faces as shown below.

Self Feature Edge Cross Vertex Cross Edge S E M E T S Y S T L U A S S A D t h g

Self Feature Vertex



Introduction to the External Shape Methodology The External Shape Methodology consists in structuring bodies for establishing the t he differentiation of features before before or after the Shell, providing providing an environment similar to the Part Design, with wi th the possibility of inserting features before or after the shell. Points to note about the External Shape Methodology: The ‘External Shape’ Shape’ is an option available in all the Shape Features Features and also in the Remove and Intersect Feature Modifiers. It allows defining the basic volume of the feature (adding the desired behavior). It can be used for reusing existing shapes created with: Functional Molded Part or Part Design bodies, Closed ‘Join Surfaces’, or surface closable by planes in its extremities. e xtremities. 



In other words, the external shape is considered considered as a solid body whatever be the type of external shape you select. The type of external shape you select could be defined using FMP, PDG or GSD, IMA, etc.




Characteristics of the External Shape You can use the ‘External Shape’ option in the following cases: Partitioning Partitioni ng of a functional functional body into ‘function ‘functional al cells’ for better better management management of complex bodies. Reuse of older models that are based on Part Design (legacy data) Transformation of surfacic shapes or imported parts into i nto Functional Bodies Improving performances performances (The body which is selected as external ex ternal shape is not impacted by the update of the main feature in which w hich the body is selected as an external shape) Controlling better the model robustness (The model can be updated step by step using local update)

Warning: Take care to put 0mm in the solid functional set that define the External shape body (in order to have a solid, not a shell)




External Shape Vs Push, Pull, Fitting The results of using using ‘External Shape’ are compared with the results of using Push, Push, Pull and Fitting: If you create a ‘Shellable ‘Shellable Featu Feature’ re’ with wall directio direction n as - ‘Outsid ‘Outside’, e’, the result is similar similar to Pull operation. operation. Optionally, ‘Pull’ can generate a ‘Protected Volume’. Volume’.

Using a Protected feature based on an external shape is identical to using Fitting feature.




External Shape Vs Part Design Union Trim The results achieved using external shape are compared with the results of Part Design Union Trim: The External or Internal feature based on an external shape can be compared to the Union trim PDG PDG operation. In FMP the shape trim is automatically automatically performed, whereas while using the Union Trim some face(s) have to be selected manually. Assume that several faces of a solid body have been selected to perform the ‘Union Trim’ operation and now this solid body is likely to be replaced by a different solid. In such case, CATIA will ask the designer to select new faces faces belonging to the replaced solid body. This behavior is quite annoying because the removed faces are difficult to locate because the solid is actually in another part. There is also the risk of forgetting some faces due to which the result of the trim could be wrong.

The benefit of FMP is that it increases the robustness while replacing the external shape by a new one because there is no reroute operation to be perform. This is particularly valuable for ‘design in context’, where the external shape is coming from an external part definition which w hich the current designer cannot control.




Applying the External Shape Methodology (1/4) You will study Functional Modeling using the External Shape methodology in comparison with the traditional (historical) (his torical) approach.


Part Design (PDG)

Open Part : External_shape_methodology.CATPart

Functional Modeling (FMP)



Applying the External Shape Methodology (2/4) Traditional (PDG)


The order of design features of the part using Part Design is given below: Pad.1 Pad.2 EdgeFillet.1 Edge Fillet.2 Shell.1 Pad.4

The order of design features of the part using FMP is given below:

Identical

Added Prism.1 Added Prism.2 EdgeFillet.1 (FMP Edge fillet) EdgeFillet.4 (using Part Design A new Body called ‘Functional Modeling Body’ A Shellable Body in the ‘Functional Modeling Body’ Body’ created using the ‘External Shape’ body for Shape definition (Shell thickness is specified) Rib (with its profile NOT constrained)


The sketch of the pad.4 forming the rib is constrained to boundries of the part.

The Shellable Body in the Functional Modeling Body is equivalent in sequence to the Shell in the Part Design Body. I.e. the two fillets, are both propagated into the Shell irrespective of if they are from FMP or PDG,



Applying the External Shape Methodology (3/4) Now the shape has to be extended with a Pad or a Prism according according to the yellow profile. Traditional (PDG)


Define in work the last feature before the Shell

Define in Work the External Shape body

Identical

Add a pad and two fillets


Inserted an Added Prism and two fillets

Identical

External Shape



Applying the External Shape Methodology (4/4) The design shall be extended with a Pad or a Prism according to the yellow profile. Traditional (PDG)


Make the Part Design Body as the In Work Object.

Make the Functional Modeling Body as the In Work Object. The shell is automatically updated and the fillets get propageted into the shell.

The Rib did not occoupy the extended shape.

Edit the Sketch for changing the constraint and getting the desired result


Identical




Part Structure and Multi-bodies When designing a complex part with a single functional body, the the tree might become very long and difficult to understand. Therefore it is necessary to divide it into several bodies according to the structure below.

Main Shape

Fixtures Bosses Holes Main Ribs

The Main Functional Body gathers the Functional Specification, GSD features and to produce the resulting geometry All these Functional Bodies gather the geometry of specific functions (Ribs, Bosses, etc.) This geometry is used in Main Functional body as External Shape.

Cross Ribs Reference Planes S E M E T S Y S T L U A S S A D t h g

Master Sketches


Order Independence and Modifiers (1/4) In the Functional Modeling concept, the behavior is embedded into features. This allows generation of geometries resulting from self-standing ‘Functional Features’ Features’ which maintain the required associativity. So the result is independent of generation order of the ‘Functional Features’

=

=

Basic and Functional Features S E M E T S Y S T L U A S S A D t h g

Whereas in all the history based systems, (Part Design for example), the geometry generated by a feature and all the required required associativity is always derived using the existing geometry which is already generated. Therefore the result is dependent on the generation order of the geometry.



Order Independence and Modifiers (2/4) However, the desired geometry cannot always be generated using ONLY the ‘Functional Features’ Features’ because they do not include all the options options necessary for generating any geometry.

Functional Features

+

Feature Modifiers + Dressup

=

Desired Geometry

To enable the generation of a complex geometry associated to a single behavior (a single functional functional feature), “(Functional) Feature Feature Modifiers” and Functional Functional Dressup features are available in FMP. These modifiers can change a geometry created by Functional Feature’s while maintaining the Functional Feature behavior. As the the ‘Feature ‘Feature Modifier Modifiers’ s’ and ‘Dressup ‘Dressup Featur Features’ es’ do not not carry a beha behavior vior in themselves, they are “sequence dependent’.





Order Independence and Modifiers (3/4) Open Part : Order_independent_and_modifie Order_independent_and_modifiers.CATPart rs.CATPart

So sometimes they have to be “reordered” for getting the desired results (i.e. when several fillets are modifying the same functional feature). For such purpose, purpose, you can use deactivate command as shown in the example below. Initial design

1. Deactiv Deactivate ate all all the modi modifier fiers s that that are childr children en of the the feature to be modified. Deactivated Edge Fillets

2. Insert Insert the req requir uired ed Edg Edgefil efillet let feat feature ure (Radius = 10mm)


3. Re Reac activ tivat ate e th the e 2 feat featur ures es..

New Edge Fillet added Position in the tree does not reflect the sequence of fillet creation see next page.



Order Independence and Modifiers (4/4) Edgefillet.4 is inserted before the the other fillets as you can see see using the parent parent children command. Like in GSD, there is no “Define in work object” for a feature in FMP, FMP, however, the ‘Autosort ‘Auto sort comm command’ and’ helps to to quickly quickly sort the the tree accordin according g the modifier modifier relation relations. s.

Edgefillet.4 was created in the tree after the existing fillets (last position)

Edgefillet.4 EdgeFillet.2 is rolling on Edgefillet.4 So, it is computed after EdgeFillet.4 S E M E T S Y S T L U A S S A D t h g

EdgeFillet.4 is now sorted according the modification relations which is not the creation order



Functional Set and Modifiers A Functional Functional Set can be used to logically group the local modifiers. Autosort Autosort command can help to quickly reorder the tree according according the modifier relations. relations. Using ‘Insert’ menu, you can create a new Functional set, then then use the command ‘Change ‘Change the Functional Functional Set’ to move the features.


Contextual menu helps to Activate/deactivate Show/hide the components put in the functional set


Rerouting Fillets and Drafts When the system detects a need for rerouting features, the current Functional Modelling implementation cannot display the situation required for identifying identif ying the reroute path (i.e the edge to reroute a fillet)(unlike fill et)(unlike in Part Design). In other words, the Solid Functionnal Set cannot display any geometry if some features are in Error.

Since R17, you can use the ‘Display only only parents’ command while editing Features in Error (the feature and all its children will be deactivated) so that you you will be able to see the current geometry along with the parents of the feature in error.


A bypass for the above problem exists in R16: Deactivate the entity (and all its children) to be rerouted: rerouted: the display is updated Edit the Entity to be rerouted for applying the appropriate selection Reactivate the entity to be rerouted




Shell Management In this lesson, you will learn important methodologies for managing Shell properties and specifications.

•

Topics covered in this course: 1. Met etho hodo dolo logy gy Gui uide de Introduction 2. Imp mpro rovi ving ng the the Perf Perfor orma manc nce e 3. Data St Stru ruc cture

4. She hell ll Ma Man nag agem eme ent


5. 6. 7. 8. 9.

Des esig ign n in Con onte text xt Desi De sign gn for for Man Manuf ufac actu turi ring ng Tip ips s for for Re Reffer eren ence ce Def efin ine e Mol Mold d Mod Model els s Cre reat atin ing g and and Usi sing ng Powercopies



Managing Design Specifications (Shell Properties) Shell Properties feature: Shell thickness is a property of the functional body: removed faces can be specified at any stage of the design because of the order independent nature of Functional Modeling. Avoid removing lateral faces if you intend to add fillet fil let on the feature. The removed faces could be extended by tangency and give unexpected result after a design change.

Preferred methodology: Lateral face removed

Opening created using a Core or Protected feature

Adjacent Tangent Faces will be removed. If you try to remove a lateral face.


Lateral faces can be removed using Core or Protected feature f eature


The Shell in Functional Modeling (1/3) In FMP, the Core of a shelled body is automatically generated taking into consideration, the effect of Basic Features, Functional Features and Feature Modifiers. However, sometimes the functionality of automatic core generation may not be successful due to complex geometry. In such cases, FMP allows you to define the desired ‘Type of Core’ Cor e’ for the the ‘Shellab ‘Shellable le Fea Featur ture’. e’. Three Types Types of Cores Cores can be selected for a Shellable Shellable Feature Interconnect Core (default) Creates the Core automatically. Generates the Core by offsetting the resulting external shape (sum of all Shellable), according to the wall thickness defined in the Shell Properties.

Interconnected Core Interconnected Core Interconnected Core S E M E T S Y S T L U A S S A D t h g

An interconnected core of a Shellable Feature is the one which flows into the interconnected core of an adjacent adjacent Shellable Feature.



The Shell in Functional Modeling (2/3) Isolated Core It offsets the faces added in the shape only for the feature in consideration. Consequently the complete body Core is the aggregation (sum) of the automatically generated Core Core and the isolated ones. ones. This is faster than the Interconnect Interconnect Core. It allows you to define a wall w all thickness for the Shellable Shapes different than the one defined in the shell properties. The only difference in the result as compared to the Interconnect Core is the possibility to generate lumps when one or more elements of the profiles supporting different features have a distance less than the wall thickness.

Interconnected Core Interconnected Core Isolated Core


In the above example, the core of Shellable Prism.1 is isolated. So the core does not flow from Shellable Prism.1 Prism .1 to Shellable Prism. Prism.2. 2. However the core of Shellable Prism.2 flows into into Shellable Prism.3 because because they both are interconnected.



The Shell in Functional Modeling (3/3) Select Core The Select Core options allows you to define the Shellable Shape Shape based on an existing core geometry. The existing core geometry can be a Solid Solid Body or a closed surface. It is particularly useful when w hen the external shape is not offsettable and/or when a variable wall thickness is desired. It also facilitates continious variation in wall thickness.

Selected Core S E M E T S Y S T L U A S S A D t h g




Solving Solv ing the the Shellabl Shellable e Featur Feature-Err e-Error or Depending upon the geometry, geometry, sometimes the body may not be ‘shellable’. In such cases you can solve the ‘Shellable Feature’- error if any.

1

Edit the shell properties

1

3

2

2


3

Select the Core tab, select the feature that cannot be shelled with others, and switch from Interconnected to Isolated core.

For the feature that cannot be shelled at all, Extract or create a surfacic Body and then select this Body as the new core.


Isolated Core Vs Select Core Isolated Core: Use this option in the following cases: When it’s already known that the shell thickness generation will w ill be in error. For editing the Shellable Features, changing core type t ype from Interconnected to Isolate Core, for fixing a shell thickness generation error. When a different thickness than the Body thickness is required for the Shellable feature. fe ature. When the required Core shall be a multi volume (disconnected volumes). To improve performances by simplifying the Core calculation cal culation


Select Core: Use this option in the follow ing cases: To define the Shellable Shape based on an existing core geometry i.e. when different wall thickness required. When it is required by manufacturing needs. For improving the performances




Creating Basic Features using Surfaces In order to create the shell when w hen external part is defined with a closed surface, you need to follow the steps given below: Create the outer surface using GSD, FreeStyle, Imagine & Shape Use the Shellable command with External Shape for Shape Definition; select the surface Use the Shell Shell properties properties command command for defining defining the wall thickness thickness and to remove remove the face(s), if required


Close surface created in GSD

Functional Solid after removing the top face


Thin Part in Functional Modeling (1/2) In order to keep the benefits of the FMP behaviors, thin Parts have to be created using at least one Core area. area. Four methodologies methodologies are possible to create a Core volume from from a non-closed Surface: Shellable Prism from Surface Up to Plane

Shellable Prism from Surface Up to XY Plane

In the Shell Property: Remove bottom + lateral faces

Closed with GSD features (refer to the Car Audio exercise)


Cavity Selected Body

Core Selected Body



Thin Part in Functional Modeling (2/2) Prism Up to Surface/Length and optionally Cut modifier from a user define Sketch(refer to the Power tool exercise)

Prism with Length

Cut modifier with Surface Design as Input

Added Thick Surface + Core Prism Feature


Added Thick Surface

Core Prism Feature

The methodology to be selected is depending of the Parting Curve or Surface needed.




Features Defining or Impacting the Shell As a reminder, here are all features fea tures that you can use to modify shell according to your needs: Name of Feature

Icon

Shellable Feature Shell Property Internal Volume Core Volume Pocket Cutout Boss Rest Reinforcement Push Pull S E M E T S Y S T L U A S S A D t h g

Cut Remove with Wall Thickness Pattern of Shellable features Any feature generating a protected (Hole) or internal volume

Do not select existing solid geometry but specify features according the function that is requested on your part



Design in Context In this lesson you will will learn some tips tips for designing in context using FMP features.

•

Topics covered in this course: 1. Met etho hodo dolo logy gy Gui uide de Introduction 2. Imp mpro rovi ving ng the the Perf Perfor orma manc nce e 3. Data St Stru ruc cture 4. Sh Shel elll Man anag age eme ment nt

5. Des esig ign n in in Con Conte text xt


6. 7. 8. 9.

Design Desi gn for for Man Manuf ufac actu turi ring ng Tip ips s for for Re Reffer eren ence ce Def efin ine e Mol Mold d Mod Model els s Cre reat atin ing g and and Usi sing ng Powercopies


Design in Context: Introduction Design-in-Context is the terminology used for designing parts based on geometry of other parts in the product.

The Functional Modeling offers the ‘External Shape’ options in Functional Functional Features and and also in Feature Modifiers. Using this option, an external body can be used to design the part. Any change in the external body automatically propagates into the design part. No user interaction or reordering is required for the propagation of such changes.

While using the concept of ‘Design in context’, you should think of the most appropriate feature to be used. For example, when a part has to be modified for fitting an external component in it, you should should use the geometry of the external component component as the ‘Tool’ for the ‘Pus ‘Push’ h’ or ‘Fitt ‘Fitting ing’’ fea featur ture. e. This recommendation may generate a complex geometry but at the same time, it will significantly increase the model robustness and allow automatic change propagation. S E M E T S Y S T L U A S S A D t h g



Features Belonging to the Design in Context Category Cate gory Based on Bodies Push Pull Fitting All the Basic Features, using body as an External Shape Based on Surfaces: Cut All the Basic and Functional Features, using a Surface in the limit(s), a Thick Surface or a surface as an External Shape Based on Sketches Pocket


Rest Cutout All the Basic Features based on sketches.




Envelope Body The Designing-in-context features based on bodies are very powerful and can provide very significant results quite easily. However, the shape of a design part which is modified using the geometry of an external part may not always alw ays be the exactly desired shape. In such cases, an “Envelope Body Body ” should be defined and used used in the Design-in-Context features.

Part.1

Part.2

Part.2 Envelope Body

Part 1 modified by Part.2 Envelope Body Tool

The Envelope body can be considered as a body derived from another body (the main body), according to some rules. FMP Functional Extraction commands allow you to build build the desired envelope body. body.


Core Extraction

Volume Extraction

Cavity Extraction

Behavior Extraction

With FM1, the only way for building the Envelope Body is to Copy/Paste the main body, then change the shell thickness to zero and delete the features f eatures that are not required. In addition to this, some features might be edited for removing the unnecessary behaviors (mainly fillets), changing limits, etc. till the desired shape, is obtained. However it should be noted that this method is not fully associative, associati ve, unless specifically fully built with parameters. The ‘Paste’ operation of a functional functional feature is supported only as “Specified in the Part Document”, therefore the full associativity is not maintained. maintai ned. While using the FMP Behavior Extraction, full associativity is possible.


Examples of Envelope Body (1/2) Model Used: Coupling.CATPart

Coupling Example: If the Coupling shown in the image below has to be supported by a series of ribs of a molded molded part, its full definition will not be directly useful in a Fitting. However its envelope body body can do the job perfectly. perfectly. Its envelope body can be offset and used for a Fitting feature and later the ribs can created and limited to the envelope body. The draft can also be imparted to the ribs. Following are the advantages of this methodology It adds the required functional gaps. It takes care of manufacturing details. It improves performance and robustness.





Examples of Envelope Body (2/2) Battery Housing Example: Complex geometry is generated for defining a battery housing, using the Battery envelope shown below.

Conceptual definition made directly from the part

This geometry is generated by a Pull Pull feature (using the envelope of the battery) and a Protected Volume, for limiting the Pull extension. Now due to manufacturing manufacturing constraints, constraints, if it is required that the faces of the battery housing should have more draft, the required modifications can be directly done on the envelope body of the battery. bat tery.


Resulting geometry on the part



Using Envelope Body Methodology You will now see the use of Extraction Behavior Behavior in the ‘Envelope Body’ methodology. Let’s assume that we have to modify Part-1, to fit Part-2 in it. Currently, Part-1 is shelled and Part-2 is not shelled. Part-1

Part-2

If you Push Part-2 into Part-1, keeping a larger and constant wall w all thickness, here is the result.

Push Part-2 into Part-1

Desired Result Part-1

Now if you shell Part-2, the end result is not the desired one.


By using the Envelope Body concept, we can get the desired result even after shelling Part-2. To achieve this, this, we have to use a New Body, Body, the ‘Envelope Body’ in Part-2, which will act as the tool for the Push operation.



Using Envelope Body Methodology: First Method (1/4) Open Product : Envelope_Body Envelope_Body.CATProduct .CATProduct

Let’s assume that the Part-2 is i s not a simple model, but has the shape, generated with a cutout.

Push Part-2 into Part-1 Part-2 (Simple)

Part-2 ( With Cutout) Undesired Result

Desired Result Part-1

The result, without using the Envelope Body concept, is not the expected one.

The adjoining image, shows the result of using the Envelope Body concept. In this case, the cavity cavit y of Part2 has been extracted and its Protected Behavior is changed to ‘Added’ ‘Added’ behavior and then then used for the Push operation.


Simply by changing the ‘Protected Behavior’ to ‘Added Behavior’ cannot always give give you the desired result. As you can see the above image, i mage, it is still not the desired result because the Cutout has affected Part-1 which w hich is not expected.



Using Envelope Body Methodology: First Method (2/4)

Part-2

Envelope Body of Part-2

Desired Result S E M E T S Y S T L U A S S A D t h g

Envelope Body excluding Cutout

Part-1

Push operation using Envelope Body

So, in this case we need need to exclude the ‘Cutout’ ‘Cutout’ while extracting the cavity for Part-2 so that the the Envelope Body which is generated gives the desired result when used with the Push operation.


Using Envelope Body Methodology: First Method (3/4) Now we can realize that an ‘Envelope body’ can be a body derived from other part excluding some features. You can also change the behavior of the extracted envelope body. Now to create a cut in i n Part-1 (as shown in image1), if you use behavior extraction of a cutout of Part-2, it would w ould generate a wall (as shown in image2) below which w hich is not desired. Image1

Image2

Automatically Part-1 is updated as below, where we can see the fillet in the side and bottom effect from the Push, including maintaining the wall thickness constant too. Desired Result Part-1

The desired result result can be obtained by extracting the ‘Volume’ of the cutout of Part-2 using the the ‘Volumes Extraction’ command, and then then using this ‘Volume’ ‘Volu me’ as the ‘Too ‘Tool’ l’ body to create a ‘Prote ‘Protected cted Featu Feature’ re’ in PartPart-1. 1. Now Let’s assume that Part-2 is modified with a Shellable Prism Prism with fillet in the side and bottom


Modified with a Prism and Fillets Desired Result Part-2

Part-1 gets updated

Part-1 automatically gets updated with the fillets and the Shellable Prism and the the wall




Using Envelope Body Methodology: First Method (4/4) Let us now assume that Part-2 has to be in contact with Part-1 at its bottom faces and there should be be a larger clearance between between the side faces of the two parts as shown.

For this, in the advanced tab of Push command, the side faces are selected as ‘Other Clearance Faces’ and a clearance value is specified. But there is a problem: the clearance on the side of the Shellable prism update update is equal to the clearance in its bottom face, which is not as intended.

But the problems is that the clearance gets propagated to the bottom faces because the faces are tangent due to the fillets.

Part-2

Part-1

The right theoretical solution requires changing the fillet profile from an arc to a c onic, for supporting the change in the clearance. This theoretical solution is not implemented yet. S E M E T S Y S T L U A S S A D t h g

A workaround consists in defining the envelope body and the relative push using another method, which is more generic.


Using Envelope Body Methodology: Second Method (1/2) Here, for the second method, we will start from the end result of first method. Create a New Body and rename it as Tool-2 Extract the behavior of the second ‘Shellable Prism’ Prism’ with the fillet in the bottom and change change its behavior to ‘Added’. Edit ‘Push’ in Part-1 and select the new Tool-2 and reset all the clearances to 0.

Result Part-1

The result of Part-1 Part-1 is as shown above because because only one feature has been extracted. Unlike in method 1, both the Shellable Prisms and all other other features which had contributed contributed to the cavity extraction have not shown their effect in the result. However the circular protected volume which was a different feature, has shown its effect in the result.


Now we will generate the required clearances in the Tool-2, using the following method: Offset the ‘Added ‘Added Behavior Behavior Extraction’ (offset all the faces as the push does). Cut the Offset feature fe ature with a plane positioned at the desired clearance distance from the bottom face (to do so, it is better to define a plane offset from the bottom face of the Shellable Prism and then cut the the Offset feature using this plane as cutting element. The differences in clearances are



Using Envelope Body Methodology: Second Method (2/2) If a sharp edge as shown is not acceptable, for any manufacturing reason,

a functional fillet can be added on the corresponding corresponding sharp sharp edge of the Tool-2. This methodology is to be used when w hen no sharp edge in the push result is desirable (irrespective of the clearance needs).

Unlike method one, we need to repeat this operation for all the Part-2 features which would would be contributing contributing to the ‘Push’ definition.

For removing the sharp edge, a functional fillet can also be inserted in Tool-2. S E M E T S Y S T L U A S S A D t h g

The result result of ‘Push’ ‘Push’ oper operation ation with difference in clearance on bottom and side faces is shown in the adjoining image.




Design for Manufacturing In this lesson, you will learn tips and recommendations for designing the parts from manufacturing feasibility point of view. You will also learn specific methods of extracting Core, Cavity and other EDM inserts.

•

Topics covered in this course: 1. Met etho hodo dolo logy gy Gui uide de Introduction 2. Imp mpro rovi ving ng the the Perf Perfor orma manc nce e 3. Data St Stru ruc cture 4. Sh Shel elll Man anag age eme ment nt 5. Des esig ign n in Con onte text xt

6. De Desi sign gn fo forr Ma Manu nufa factu cturi ring ng


7. Tip ips s for for Re Reffer eren ence ce 8. Defin efine e Mol Mold d Mod Model els s 9. Cre reat atin ing g and and Usi sing ng Powercopies


Design for Manufacturing: Introduction The Draft Properties feature allows to specify the draft even before creating the features, thus enabling a draft orthogonal to the Function Function direction too. In molding, this capability capability is useful for predefining specific pulling directions for different sliders of the mold tooling. As far as possible you should use the Drafts and Fillets which w hich are intrinsic to the Functional Features to improve the design stability and to make the specification specifi cation tree look more simple. You should use the ‘Functional Draft’ Draft’ when the draft cannot be inserted directly in the Features.


Use the Part Design Draft only when none of the above method is applicable. Even in this case it is i s possible to build a very robust model, if only one feature is involved or all the involved features features have the same behavior. behavior. The following workaround workaround can be used: (this workaround is also valid for the fillets): fillets ): Copy the Features that require the draft, (including any existing ‘Draft ‘ Draft Properties’) and Paste them into a ‘New body’ If the behavior behavior of the features features is different, different, change change it to ‘Added’ ‘Added’ or ‘Cavity’ ‘Cavity’ as required. required. Apply the required required Draft, according to the above methods. methods. Include ‘Part Design Draft’ if necessary. Delete the copied features from the Part body Make the Part Part body as the ‘In Work’ Work’ objec object. t. Create ‘Basic Feature’ using the new new body, and apply apply the desired behavior. behavior. You can also use use ‘Power Copy’ Copy’ to define advanced functions. functions.




Applying Draft using Tools (1/2) Using the ‘Envelope Body’, you will see how drafts can be applied easily: easil y:

If draft is applied to Part-2, Part-1 automatically gets updated. The Push feature propagates the draft to Part-1.

If Part-1 requires a different draft than Part-2, due to material difference, the draft can be applied to the envelope body, to maintaining full associativity. associativit y. If you apply draft on the faces of Part-1, it i t would decrease its robustness.

With Envelope Body Definition - method two (only (only R16) following steps should be followed:


Make ‘ToolMake ‘Tool-2’ 2’ as the the ‘In Work’ Work’ obj object ect.. Side Faces Deactivate the functional edge fillets, if any Create two functional drafts selecting the side faces and the neutral elements. Reactivate the edge fillets, if any. Update Part-1, ( End result is shown in the adjoining image) Applying Draft


Applying Draft using Tools (2/2) This methodology can also allow you to build drafts in opposite directions (but in this case Part-1 cannot be manufactured).

Any modification in the shape of Part-2 gets automatically propagated to Part-1.




Walls with Different Drafts (1/2) Constant Wall Thickness cannot be maintained in this case, different solutions possible, according to the requirements Case 1: If Part-2 has no fillet in the bottom part and no fillet is required in the push result, You can use the Draft modifiers, and draft the internal faces generated by the Push, (where a different draft angle between the internal and external faces is required). Case 2: If Part-1 requires a fillet in the internal faces generated by the push, and also requires a different draft as compared to the faces of Part-1, you have to generate an additional tool body because the draft modifier cannot be added after a fillet resulting from the offset operation. The additional tool body can be generated in the following way. In a new body, create an Added Feature using extracted body from Part-2. (This new body will be used for the Push operation) S E M E T S Y S T L U A S S A D t h g

Offset the new body imparting the required clearances. Draft the required faces. Fillet the required edges using functional fillets.



Walls with Different Drafts (2/2) Now you can use the newly created body body as a tool for the fitting operation. Using this newly created body as an external shape, create a Push operation. With this approach the Push in Part-1 can be converted in a Fitting, since the result is the same (all faces are generated by the envelope body)

This approach allows managing three different drafts: one in Part-2 one on the external faces one on the internal faces





Generating Different Drafts between Faces If the result of ‘Push’ operation should should have a fillet in the bottom bottom of the part (due (due to manufacturing reasons or due to design requirements), the desired result can be obtained using the following process: Create a new body Tool-3, extract the required features from Part-2 excluding the fillets which are tangent to the faces to be drafted. If the fillets are internal to the t he features, remove them from the features and create explicit functional fillets. This will help us extract a Functional Feature excluding the fillet.

Build a new body (Tool-4), and extract features from Tool-3 without the fillet. Part-2


Now you can use the method specified in the previous slide to get the desired result.

Part-1



Walls with Different Different Drafts Drafts between between Faces: Faces: R16 – (1/4) If the result of ‘Push’ operation should should have a fillet in the bottom bottom of the part (due (due to manufacturing reasons or due to design requirements), the desired result can be obtained using the following process: The design requirement is that Part-1 is to be modified for housing (supporting / fitting) Part-2 Conditions as follows:

Part-1

Part-2 has already been drafted. Part-2 drafted. Part-2 is filleted around the area to be supported. Part-1 requires a different draft on its internal and external walls which shall be generated for supporting Part-1. The draft on the external wall of Part-1 should be different from the draft applied to Part-2. The housing of Part-2 shall have a clearance on all the lateral walls, where as the supporting wall shall allow the tw o parts to be in contact (OR – The lateral and supporting supporting walls should have different clearance values) The two parts are already positioned. Part-1 has some faces removed, for making the following steps easier to understand. S E M E T S Y S T L U A S S A D t h g

We’ll define two tool bodies, one for the external part (Tool-Ext) and one for the internal part (Tool-Int) Tool-Ext will define the support for external walls, wall s, including the clearances, drafts and fillets.

Part-2


Walls with Different Different Drafts Drafts Between Between Faces: Faces: R16 – (2/4) Definition of Tool-Ext: If there exists any fillet in Part-2 which is internal to a feature and which is around the area to be supported, remove it from the feature and add a Functional Fillet at that location. In Tool-E: Using the ‘Behavior ‘Behavior Extraction’ tool, extract the Feature of Part-2 which contributes to the lateral faces which are to be supported by Part-1. Change the extracted behavior of the feature to ‘Added’ ‘ Added’ Offset the Behavior Extraction, according to the larger clearance (Clearance required at the lateral walls) The offset will result in addition of material in all directions, and the amount of material added on the the bottom face is not as as desired. So Cut the result of offset at the bottom using a plane. The plane used to define the bottom clearance should be defined by offsetting the bottom face of Part-2. Apply a Functional Draft on the lateral faces for providing the required draft for the external walls. Add a Functional Fillet on the bottom face edge which is generated by the cut. Radius of the fillet should be equal to the ‘bottom-fillet of Part-2’ + ‘the lateral clearance’. S E M E T S Y S T L U A S S A D t h g

Cut

Draft

Edge Fillet



Walls with Different Different Drafts Drafts Between Between Faces: Faces: R16 – (3/4) Definition of Tool-Int: Using the ‘Behavior ‘Behavior Extraction’ tool, extract the Feature of Part-2 which contributes to the lateral faces that are a re to be supported by Part-1. Change the extracted behavior of the feature to ‘Added’ ‘ Added’ Offset the Behavior Extraction, according to the larger clearance (Clearance required at the lateral walls) Cut off the Offset for defining the supporting wall thickness. Use a plane to cut the offset. It is recommended to define a plane at distance = wall w all thickness + bottom clearance. Apply a Functional Draft on the lateral faces for providing the required draft for the internal walls. Add a Functional Fillet on the bottom face edge which is generated by the cut. Radius of the fillet should should be equal equal to the ‘bottom-fill ‘bottom-fillet et of Part-2’ + ‘the lateral clearanc clearance’ e’ or larger. larger.


Offset and Cut

Draft

Edge Fillet




Walls with Different Different Drafts Drafts Between Between Faces: Faces: R16 – (4/4) Let us modify Part-1 housing (supporting) (supporting) Part-2: Use the the ‘Fitting’ ‘Fitting’ comman command d and select ‘Tool‘Tool-Ext’ Ext’ as the ‘Too ‘Tooll Body’ Body’ for the the Fitting command. (Push (Push is not used because performance performance of ‘Fitting’ is better than ‘Push’). Create Crea te an ‘Intern ‘Internal al Feature Feature’’ and select select ‘Tool ‘Tool-Int’ -Int’ as an ‘Exter ‘External nal Shape’ Shape’ for the Internal Feature. Shellable Prism

Fitting

Internal Body S E M E T S Y S T L U A S S A D t h g

Result obtained is shown in the above image. The result satisfies sati sfies all the needs and all the conditions, and also provides larger model robustness.


Drafts on Faces generated by Push or External Shape The problem here is that we need to modify the blue part (already divided) to adapt it to the orange part, keeping some clearance. Both parts are designed completely with FM1. In this example, the complete real life l ife part has not been shown for confidentiality purpose.

Tool Body

The push, with clearance, generates the expected result, impacting the bottom part only. But the draft analysis shows shows an undercut undercut on the faces, generated by the Push. This This undercut has to be eliminated.




Functional Draft with Tangent Continuity (1/3) Applying the draft intrensic to the features of the part, applies draft on all the faces. It does not take into account the faces generated by the push operation.

The faces to be drafted are identified and shown shown below. The Part Part Design or Functional Functional Draft cannot be applied to draft this configuration of geometry. So the part should be simplified by removing the fillets. The draft draft can be applied after removing the fillets which can be later rerouter and fixed.


Fillet to be removed

Faces to be drafted




Functional Draft with Tangent Continuity (2/3) The orange orange part was completely built using Functional Functional Modeling. Modeling. An instance of it can be obtained in the following three ways: - With Relational Design (Cut & Paste) (the result is not fully associative) - With the Extractioin Behavior (FMP) (the result is fully associative) - With the Design Collaboration Collaboration (CD1) (the result is fully associative) Deactivating all the fillets, the part becomes as shown in the adjoining image. For the ‘Neutral Element’, a surface can be built using the profile which has been used to generate the basic shape.

All Fillets Deactivated

A Functional Draft can be created by selecting one of the faces f aces to be drafted, and the Neutral element above.


The surface which will act as the neutral element


Functional Draft with Tangent Continuity (3/3) After applying the draft, the fillets have to be rerouted. At the bottom of the faces f aces which are drafted, new new edges are developed as as a result of draft. These edges may generate some discontinuity which has to be fixed. Analyzing the edge shown in the first image below, a tangent discontinuity larger than the one allowed by the fillet is shown.

Edge causing a Tangent Discontinuity

Edge causing a Tangent Discontinuity is filleted.

Adding a Function Fillet on the edge causing c ausing the discontinuity, the problem is fixed, as shown in the second image above. Activating all the remaining fillets, the desired draft result is obtained. Faces are drafted and the tangent tangent continuity continuity is maintained maintained . The result of the push now now sho shows ws the appropriate appropriate drafts. drafts. From the draft analysis, you can notice that there is no undercut. S E M E T S Y S T L U A S S A D t h g



Removing Undercuts using an Envelope Body A push operation may sometimes generate an undercut. The image below shows a simplified representation of such case. To remove such undercut, you can use the following process: Create a new body and add the component body in it. Offset this body with a larger clearance.


Thicken the required faces for adding material. To have different offset values at bottom and lateral faces, cut the faces of this new tool body using planes. Build a plane passing through the two lines. One of the line should be along the pulling direction through the vertex and the other line should be the component edge. Cut the added material with this plane, with an offset equal to the clearance desired on this face Apply a Part Design draft angle on the face which w hich has resulted from the cut operation recently. Use this body as a tool in a push operation (without clearance) for obtaining the desired result.



Local Thickness (1/2) Following are the ways to locally change the thickness of of a wall: Selection of a face of the Solid Pros : It provides direct and easy access to elements that are to be modified Cons: The design may not be robust in case of change of the solid. Add new specifications (new features or modifiers) Pros: Specifications can be easily managed. Wall thickness can also be changed using one of the following methods: By assigning different shell shell thickness using the Advanced Advanced tab in the Shell Properties Properties dialog box. By assigning different thickness thickness using Functional Functional Feature (‘Core Feature’, Feature’, or ‘Thickness Feature Feature ) By using – [ Volume Feature Feature + Thicksurface-Option]: This thickness thickness of a face can be modified using the ‘Thick Surface’ option as shown below. below.


Pros: As this method is based on functional feature and functional need, it is i s more robust. Cons: If a face has participated p articipated in more than one feature, the functional feature (used to modify thickness) has to be be applied to each feature feature in which the face has participated,



Local Thickness (2/2) By using the appropriate Shape Prism and selecting the face to be thickened. This method provides a result which is different than the Thick Surface command. Pros: As this method is based on functional feature and functional need, it is i s more robust. robu st. The ‘Protecte ‘Protected’ d’ and ‘Remove’ ‘Remove’ Featu Feature re can also be used used to reduce reduce the thickness. Cons: If a face has participated p articipated in more than one feature, the functional feature (used to modify thickness) has to be applied to each feature in which the face has participated, deactivating the other ones. Using the the ‘Dress-up ‘Dress-up Feature’ Feature’ ‘Thic ‘Thickness’ kness’ of (Part Design) Design) you can modify modify the thickness thickness of a selected face of the functional functional solid. For the ‘Thickness’ ‘Thickness’ feature, positive value can be used to increase thickness and negative value to reduce the thickness. Pros: It is very easy eas y to use this method. It is good for last minute adjustments of local thicknes thickness s (i.e after flow flow analysis). analysis). Cons: This method does not follow the functional approach. And can be deployed only after the final result of the functional solid.





Tips for Reference In this lesson, you will learn various tips, which will be useful during the general use of FMP workbench.

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Topics covered in this course: 1. Met etho hodo dolo logy gy Gui uide de Introduction 2. Imp mpro rovi ving ng the the Perf Perfor orma manc nce e 3. Data St Stru ruc cture 4. Sh Shel elll Man anag age eme ment nt 5. Des esig ign n in Con onte text xt 6. De Desi sign gn for for Man Manuf ufac actu turi ring ng

7. Ti Tips ps fo forr Re Refe fere renc nce e S E M E T S Y S T L U A S S A D t h g

8. Def efin ine e Mol Mold d Mod Model els s 9. Cre reat atin ing g and and Usi sing ng Powercopies



Extend Internal Features Outside the Core (1/3) The following explanation provides tips to extend the ribs across the shell volume as shown in the image below.

image-1

Image-2

The above image-1 shows a volume which is cut by a surface. The magenta colored faces are the faces that are removed using Shell Properties command. Image-2 shows the desired result.

The simple way to get the desired result is to use the option Extention Type = ‘Across Removed Faces’ but it has several draw-backs draw-backs like the rib extends sometimes may produce and undesired result if the rib sketchs are not constrained to the edges e dges of the part. Such constraining may also create update cycles.



Extend Internal Features Outside the Core (2/3) Another possible way is:  Create a ‘Rib’ / Internal feature as usual (No extension) extension) Extend the internal shell volume volume using ‘Core ‘Core Feature’ as shown above. 

Rib Feature maintains the rib inside the shell volume.


Core feature extends the shell volume and the rib propagates into the extended shell volume.

In this way you can extend the internal / rib feature outside the default shell volume by eventually extending the shell volume using ‘Core Feature’.



Extend Internal Features Outside the Core (3/3) A third methodology consists of dividing the basic shape instead of cutting: Define the basic shape upto the level of the extension required

Instead of cutting the shape with the surface, or a plane, or removing a face, divide the basic shape with the surface or plane. For Undivided Volumes Field in the Divide Feature dialog dialog box, the ‘Core’ option. Keep only the desired desired side of the ‘Divide’ ‘Divide’ featur feature. e.


Apply the rib in the divided body.

The rib is properly generated, even if the profile extends beyond be yond the shape




Volume Creation from a Surface Volume of any behavior can be created created from a solid body. body. However it can also be create from a surface if the surface openings can be closed by planar faces.

Surface opening that can be closed by a planar surface

Shellable volume created using the Surface. After removing a face

If the surface cannot be closed by a plane, close cl ose it (using GSD Fill), create the volume. Surface opening that cannot be closed using a planar surface


Close it using GSD ‘Fill’, join if required.

And then create the Volume.


Use Joined Surface for Cut If you use Cut feature to trim the Functional Body using a surface, the surface you use should be joined. Use GSD Join feature to join the surfaces.

Use joined surface to cut the ‘Functional Solid’.


For using surfaces for cutting or trimming Functional Body, the surfaces should be joined.



Use Up to Plane/Surface Limit or Cut Feature Basic Features and many many Functional Functional Features support the ‘Up to a Plane’ or a ‘Surface’ option, including an optional offset, as limit. These limiting options are useful w hen you want to limit the the ‘Shellable ‘Shellable Featu Features’ res’ to pre-design pre-designed ed styling styling surfaces. surfaces. “Up to” Pro Pros: s: Up to surface is valuable when w hen the targeted surface is used as limiting reference. Very large scope of industrial features can be created related to only one reference surface (for example example - Flange, engraving engraving or local thickness change etc). Up-toSurface makes a Functional Functional Volume or Feature generating directly the desired geometry. This simplifies the specification tree. The result of ‘Cut Feature Modifier’ is mostly similar to the ‘Up to Surface Option’. Optionally it can generate a ‘Functional ‘Functional Fillet’ at the intersection of of the surface and shape it cuts. It also provides the facility of different wall thickness. “Cut “C ut” ” Pr Pros os:: ‘Cut’ allows cutting the same feature by multiple surfaces. Using the Cut Feature provides a more understandable specification tree (the used cutting element exists in the specification specifi cation tree). The Cut is suggested to be used for modifying the features in one go, when the limiting surfaces are not available up front. The Cut also allows to manage different design shape configuration configuration by using several cut features for different configurations and keeping only one of these activated at a time. S E M E T S Y S T L U A S S A D t h g

Warning: Avoid using “Up to” with a ‘Face’ belonging to the current current functional solid unlike you do in Part Design because this creates a link between feature and and creates a history/ dependency relation. It is recommended that you create a reference reference element (plane, surface) and then create all your features based on the reference elements. elements. Using this method, you will also be able to manage design change using a simple simple ‘Replace’ command. The reference elements elements can be easily located as compared to an internal internal face of a solid.




Parting Radius in the Draft Properties Definition (1/2) Open parting_radius.CATP parting_radius.CATPart art This option is a workaround to solve some issues that arise when the lateral fillets get distorted if the ‘Draft both both sides’ option is used: Open parting_radius.CATP parting_radius.CATPart art You can see that the fillets fillet s are not correctly limited on the parting element Edit the Draft Properties Put 1mm as Parting Radius You can see the lateral fillets are now re-limited by the parting fillet

Parting plane: No sharp edge


But if designer wants a sharp edge for the parting, an other methodology has to be used (see it next slide) Parting plane: Sharp edge


Parting Radius in the Draft Properties Definition (2/2) Open: Parting_Radius_Not_Allowed.CATP Parting_Radius_Not_Allowed.CATPart art If the designer wants a sharp edge for the parting, the recommendation is : Alternative1 : create one body for each side of the parting element and then import the result in the Partbody


The exact expected solution (when the parting is not planar) is provided by the Cast Forged Optimizer (CFO) product (PDG toolbar advance dress up feature).

Alternative2 : Use a feature with local modifier limited by the parting plane.




Possible Ribs Creation Ribs can also be created using any one of the following follow ing way:

Main Shell

‘Rib Body’ Body’ used as Internal Internal Feature Feature in Main Shape Definition

Ribs in Auxiliary Functional body (Added features) S E M E T S Y S T L U A S S A D t h g

Shape created in the Rib Body must be “Added” or any function that adds to the cavity in order to be used in the main body. Otherwise the shape has no representation (unless there is a shell) and the functional solid is empty.

The advantages are: You can precisely control Rib definition (Variable thinness as example)



Defining Mold Models In this lesson, you will see specific aspects when your y our are defining Mold Models.

•

Topics covered in this course: 1. Met etho hodo dolo logy gy Gui uide de Introduction 2. Imp mpro rovi ving ng the the Perf Perfor orma manc nce e 3. Data St Stru ruc cture 4. Sh Shel elll Man anag age eme ment nt 5. Des esig ign n in Con onte text xt 6. De Desi sign gn for for Man Manuf ufac actu turi ring ng 7. Tip ips s for for Re Reffer eren ence ce

8. De Defi fini ning ng Mo Mold ld Mo Mode dels ls S E M E T S Y S T L U A S S A D t h g

9. Cre reat atin ing g and and Usi sing ng Powercopies



Mold Model Example Let us study an example of a mobile phone part shown below to study the extraction of core, cavity and other mold inserts.

The Part

Core for milling


M

bl i

Cavity for milling

t

EDM Base for Core

Cavity Inserts

C

it

d l

lt



How to Extract the Core as it is in the Part Model

The Part

Use Core Extraction command for extracting the “Core”, as per the shape of Part.

Using the ‘Added Feature’, create its base upto the ‘Parting Surface’ The Resulting Core


This resulting core is the core as per the shape of Part. The Core for milling is extracted in



How to Extract the Cavity as it is in the Part Model

The Part

Use Cavity Extraction command for extracting the “Cavity”, as per the shape of Part model. The result is a Protected Volume. The Resulting Cavity


This protected volume volume when substracted from from the ‘Added’ block (creating using ‘External ‘External Feature’ gives the cavity exactly as per the shape of Part. To get the the Cavity, create an added Cavity Block using Added Feature upto the parting surface. The result of this operation is shown above.

This resulting cavity is the cavity cavity exactly as per the shape of Part. The cavity for milling is


How to Define the Core and Cavity for Milling (1/2) The Extraction Properties command allows you to exchange the default assignment of features selectively to Core or Cavity. Using this tool you can switch swi tch the protected volumes to affect either the core or the cavity. The difference in result caused by such operation is shown below.

Extraction Properties (in the Part)

Part Body default

The Part


Old Cavity

New Cavity

Now the new Cavity is closer to the expectations, but not yet ready for milling.



How to Define the Core and Cavity for Milling (2/2) In the “Added “Added Extracted Extracted Core” Core” of the Core body exclude the features not to be milled

Core


In the “Protected Extracted Cavity” of the Cavity body exclude the features not to be milled

Cavity

Cavity for milling.



How to Define the Model for EDM Tools (1/2) Following are some recommendations / facts necessary to define the EDM tools


Extract Volumes from all Features Extract Features of Part defined for reserving spaces (except the holes). Change the ‘Protected’ ‘Protected’ behavior of the extracted volumes to ‘Added’. Extract the features to be machined separately from the Part body, using the Behavior Extraction, changing their behavior to Added, (normally the Ribs and Internal I nternal Shapes) Extract any Push/Pull features if present (the extraction just generates a protected volume equivalent to the push tool body) Push, Pull and other functional features are not yet fully supported by the Behavior Extractions, therefore they need to be recreated in each body required for tooling. The effect of a Push feature can be propagated into the Core using a Pull feature with the same tool body with clearance = 0 and Wall thickness thi ckness = Push (Wall Thickness + Clearance) [ without w ithout the Protected Volume option]. This is necessary to generate a solid equal to the push tool body + the wall thickness thickness and the defined defined clearan clearance. ce.

This can be the model for drilling and a fixed insert too



How to Define the Model for EDM Tools (2/2) The following explanation and example can be applied for building EDM tools. For each element (isolated from a feature):


Show its Profile Copy/Paste the feature into the same Functional Body Rename the copied feature according to its parent name plus a suffix. Edit the copied feature by changing the profile using the “Go to profile definition” option or use the Output/Profile Feature in the sketch and select the elements of the sketch to be isolated. i solated. Once the isolation of features is completed, you can deleted them without deactivating the aggregated elements. An isolated element can be obtained in a new body, using the extraction behavior on any one of the isolated features. Later the behavior of all the protected features should be changed to Added. Extract Volume of all the Protected and Hole Features. Change the Protected behavior of the extracted features to Added. Perform a Behavior Extraction of the isolated feature, changing its behavior to Added From the Parting Line, (or a similar construction element), limit the extracted ex tracted features using a ‘Cutout’ with no wall thickness and and the ‘Complement’ option.

In such a way the design model represents the manufacturing model too, and any change will automatically update the tool model. A document per each isolated tool can be obtained using the Instant or the Design Collaboration.




How to Define the Model for Fixed Inserts The following explanation and example can be applied for building Fixed Inserts. Extract the protected volumes and all other volumes in the Part defined for reserving space (except holes). Change the behavior of these volumes to Added.

For geometry defined with any Protected Feature: Perform a Behavior Extraction of the Protected Feature, and change its behavior to Added.

For other geometry: Extract the desired feature(s), change the behavior to Added. Make sure that you relimit the extracted features, wherever required.


For Geometry defined using a Push: Create an Added Body using the Push tool as the External Shape.

The Part


How to Insert the Shrinkage Normally the shrinkage is inserted when a model for tooling is complete. However, How ever, the shrinkage can even be inserted at the begining of the tooling model. Following is the process to do it. Use the Transform type = Scale, specify the shrinkage center (reference) and factor (scale) (Transform type Affinity allows you you to define non homotetic shrinkage factors) Apply the Transform to the Extracted Core & Cavity and also to any other feature extraction done from the original Part Body. Note: This method significantly reduces the number of times shrinkage has to be introduced, but it might occasionally generate impossible geometry. Individual shrinkage can also be applied on any extracted feature.




Simulating Results of the Models Defined for Molding Goal here is to obtain the volume of the part before shrinkage (real volume of the mold cavity) cavit y) This is just a boolean process using all the bodies of the mold:

1.

In two two new new bodies bodies,, defin define e the the resul resultt of “mac “machin hining ing” ” the Co Core re & Cav Cavity ity resp respecti ectivel vely: y: Add the body defined for milling Remove the bodies defined for EDM or other machining type Add any insert

2.

In a new “Result” body Create an ‘Added Prism’, using the profile used for defining the Core & Cavity bases, For this Added Prism, the limits should be from the ‘Core base bottom limit’ to the ‘Cavity ‘Cavity base upper upper limit’ Remove the two bodies bodies “Core & Cavitry machined” machined” defined above to get the result.




Creating and Using Powercopies In this lesson you will learn to create and store interactive interactive features. You will also learn to reuse and adapt them to a new context.

•

Topics covered in this course: 1. Met etho hodo dolo logy gy Gui uide de Introduction 2. Imp mpro rovi ving ng the the Perf Perfor orma manc nce e 3. Data St Stru ruc cture 4. Sh Shel elll Man anag age eme ment nt 5. Des esig ign n in Con onte text xt 6. De Desi sign gn for for Man Manuf ufac actu turi ring ng 7. Tip ips s for for Re Reffer eren ence ce 8. Def efin ine e Mol Mold d Mod Model els s


9. Crea Creati ting ng an and d Us Usin ing g Powercopies



What is a PowerCopy? PowerCopy is a set of design features grouped together in order to be reproduced: it is a kind of advanced copying tool. You can edit it (set contained features, entries, previews …). You can instantiate and customize it in the design of any part.

PowerCopy tools are available in the Insert menu (Advanced Replication Tools) of those workbenches: Part design Wireframe and Surface Sheet Metal Design Functional Molded Part Advantages of Functional PWC: Easy to create Robustness S E M E T S Y S T L U A S S A D t h g



Recommended Structure For a PowerCopy Since R16, the following structure is recommended : Functional Set (Feature to select for creating a PowerCopy) |- Func Functiona tionall Spec Spec1 1 |- Func Functiona tionall Spec Spec2 2 |- Sk Sket etch ches es |- GSD

Advantages : After instantiation if there is only one node that is collapsible, delete operation is easily possible.





Reusing Existing Part Design Templates You can assign a behavior to the existing Part Design templates For a complex template, it may be more productive to reuse certified design components that are already defined in Part design by adding a functional behavior to them.

1

Create an Internal Feature by selecting template’s main body

2

Edit Existing Power Copy

3

Select the inputs again starting from the ‘Internal Feature’.

The Po Power wer Copy created this way can be be instantiated in the the usual way: The template instantiation protocol does not change from its part design one. Once a behavior is defined, there is not need for a “Union “Union Tim” or any other other Boolean operation after instantiation. 1 S E M E T S Y S T L U A S S A D t h g

Instantiate Template.CATPart and select inputs as shown.

2

Pattern the instantiated feature. Note that its functional behavior is preserved. Final


How to Use PowerCopy (1/2) To use your PWC open the part where you want to instantiate the Power Copy. Create a shell with wi th function design features. Using the sketch, create points to position the screw holders.




How to Use PowerCopy (2/2) Select Catalog Brower icon : Search your PWC Select inputs in the order they are asked XY plane Point Click on Parameters If required, change the parameters of the published values.




Additional Information (1/3) The recommendations recommendations for creating PowerCopies PowerCopies are given below: below: Whole bodies or Functional Sets can be selected to make your PowerCopy and it is recommended to do so because after instantiation, it will be easier to identify the result of a PowerCopy instantiation. For example if it is in an external body it can be easily eas ily deleted. Try to have less geometric inputs as possible : While creating geometry that will make up a PowerCopy, try to select references (supporting faces, directions) on existing geometry that will also make up the PowerCopy (except for cases where you want them to be controlled controlled during the instantiation). Try to make geometry in the sketch iso-constrained (green lines).





Additional Information (2/3)

When you instantiate a PowerCopy from a CATPart containing several ones you can choose it through the reference

If you want to use the PowerCopy several times, check the repeat option.


Use identical names allows the automatic selection of the geometric inputs that have the same name as



Additional Information (3/3) When selecting a supporting supporting face for a sketch, it is recommended to select the face of a positioned and oriented local system instead of a face of the geometry. In the first case position and orientation of the axis in the created sketch will be controlled


Here, the face selected to support the sketch is a face of a local axis system: origin of created sketch is the origin of the local axis and the H and V axis orientations are determined by the local system

In the second case position and orientation of the axis in the created sketch will be uncertain

Here, the face selected to support the sketch is a face of a the geometry: origin of the created sketch is a vertex of the selected face and orientation of H and V axis is not the expected one


To Sum Up You have learned: What is a PowerCopy PowerCopy is a set of design features grouped together to be reproduced. It is an advanced copy tool. PowerCopy tools tools are available in Insert menu in Part design, Wireframe and surface, sheet metal design workbenches.

How to create a PowerCopy During creation you have to set definition, identify and name inputs, publish parameters, choose icon and preview. How to save a PowerCopy Saving of PowerCopy is necessary. If not saved, PowerCopy can never be instantiated. This can be done through Insert menu > Knowledge Templates > Save in catalog. S E M E T S Y S T L U A S S A D t h g

How to instantiate a PowerCopy For instantiation you have to first select PowerCopy which has been previously created. This can be done through two ways. First way is through catalog and second way is from Insert menu > Instantiate from document.


Catia Functional Design

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