PTC官方培訓(xùn)_Top-Down Design.ppt

1、Top-Down Design ToolsManaging Complex Assemblies Victor RemmersHolland Engineering Consultants BV,Tips & Techniques,Top-Down Design Philosophy,Traditional Design Approach,“Bottom-Up Design” Design of individual components independent of the assembly Manual approach to ensure that components fit prop

2、erly and meet the design criteria Components and those placed in sub-assemblies are brought together to develop the top-level assembly Errors are manually identified and modifications to each component are made to make the adjustment. As assembly grows, detecting these inconsistencies and correcting

3、 them can consume a considerable amount of time,Top Level Assembly,Component Design,Component Design,Component Design,Possible example Bottom Up?,Mate,Top-Down Design Philosophy,“Top-Down Design” Method of placing critical information in a high-level location Communicating that information to the lo

4、wer levels of the product structure Capturing the overall design information in one centralized location,Design Information,Component,Component,Component,A more integrated approach.,Top Down Design Stages It is a concept.,6-Stage Process,Conceptual Engineering Phase Layouts and Engineering Notebook

5、Preliminary Product Structure Phase Pro/INTRALINK, Model Tree Capturing Design Intent Phase Skeleton Models Manage Interdependencies Phase Reference Viewer & Reference Graph Communication of Design Intent Phase Copy Geoms, Publish Geoms & Shrinkwrap Population of the Assembly Phase Automatic Compone

6、nt Constraints & Component Interfaces,The Bobcat example,Conceptual Engineering PhaseLayouts and Engineering Notebook,Understand Existing Situation High-level Requirements Space Allocation Define New Space and Motion 2D Sketches 3D Models Rapid Iteration & Convergence Animations Capture Key Design I

7、ntent Parameters Notes Spreadsheets Proprietary Data,Stage 1,Preliminary Product Structure Phase Pro/INTRALINK, Model Tree,Quickly define product hierarchy Before any of the components geometry is defined Intuitive, automatic mapping to “start models” Templates ensure all designs share the necessary

8、 common elements such as layers, views Copy from start models Automatic assembly of default datums Unplaced, Partially- & Over-Constrained Components,Stage 2,Capturing Design Intent Phase Skeleton Models,What needs to happen? Capture conceptual design parameters within the context of the assembly Ca

9、pture & control critical object interfaces in a single, convenient location How? Skeleton Models Centralized pathway for communication Facilitate task distribution Promote well-organized design environments Enable faster, more efficient propagation of change Special Treatment in BOMs, Simplified Rep

10、s, Drawings, Model Tree & Mass Property Calculations Uniquely supported Scope Control Setting,Stage 3,Manage Interdependencies PhaseReference Viewer & Reference Graph,Stage 4,Tools to Manage References External Reference Control Ensures Top-Down Design methodology is followed Incorporate design mana

11、gement rules directly into the design Ensures proper design reuse Pro/INTRALINK Model Tree Global Reference Viewer Reference Graph,Communication of Design Intent Phase Publish Geoms, Copy Geoms & Inheritance,Publish Geometry Features Provides ability to pre-determine the geometry to be referenced by

12、 a Copy Geometry feature Allows designers to define their interfaces to the rest of the design Copy Geometry Features Allows copying of all types of geometry Surfaces, edges, curves, datums, quilts, copy/publish geometry Retains copied geometry name and layer settings Dependency on parent geometry c

13、an be toggled Can be “Externalized” External Copy Geometry Build relationships on external models independent of an assembly Useful for coordinate system assembly practices Inheritance Inherit model geometry for one-way associativity Shrinkwrap (included in Foundation Advantage Package),Stage 5,Popu

14、lation of the Assembly PhaseAutomatic Component Constraints & Component Interfaces,Stage 6,What tools are available for populating the assembly? Assembly Tools Drag & Drop Placement Component Interfaces Component Creation Within the context of the assembly Mirror Parts or Subassemblies,How does Top

15、Down Design relate to company goals?,Four Goals from Upper Management 1) Cycle Time Reduction. 2) Increase User Satisfaction with Software. 3) Margin Increase. 4) Cost Reduction.,Why should you use it?,Benefits: Reduced design time Reduced errors (right the first time) Increased quality Better proje

16、ct management visibility Concurrent engineering Confidence in top-level regeneration Knowledge of how modules interface Top-level change control,Example: to design an alternator.,What information should a designer need to work with most times?,Complete Top-Level Assembly 540 MB,All Skeleton Models i

17、n Top-Level Assembly 70 MB,Neighboring Subassemblies 320MB,Subassembly, with Skeleton Model containing all required information 20 MB,What does an example look like?,Three Phases,Pro/INTRALINK Pro/CONCEPT ISDX Pro/ENGINEER Pro/NOTEBOOK,CONCEPTUAL DESIGN,CAPTURE DESIGN CRITERIA,DETAILED DESIGN,Produc

18、t Definition,Product Definition: Engineering Layout,What it is:,First thing done in design cycle,What it is Not:,Used to evaluate key interface points,Used to evaluate key components of project,Three dimensional solids,Fully detailed,Advantages of Using a Layout,Document design information in one ce

19、ntralized location Document design information before creating solid models Investigate design options without involving the entire assembly Easily make design changes because all of the design information is contained in one location,#2 Product Definition: Assembly Structure,What it is:,Virtual Ass

20、embly / BOM,What it is Not:,Used to organize assembly & assigning of design tasks,Used to input non-geometrical data up-front,Three dimensional solids,Fully detailed,Fully constrained,Advantages of Defining Preliminary Product Structure,Defining the product structure prior to defining geometry can a

21、ssist you in organizing the assembly into manageable tasks that can be assigned to design teams or individual designers. Associate specific library parts (that are to be used on the project) with the assembly at the start of the design, preventing confusion later.,Advantages of Defining Preliminary

22、Product Structure,Cont Submit the assembly to Pro/INTRALINK or PDMLink and assign models to the appropriate vaults or folders. Individual designers can focus on specific design tasks instead of on how their design is going to fit into the overall structure. Input non-geometrical information such as

23、the part number, designers name, etc., at a very early stage.,#3 Product Definition: Skeletons,What it is:,Zero-mass geometry,What it is Not:,Exact location detail,Three dimensional solids,Fully detailed,Minimized geometric detail,And Definitely Not This!,Advantages of Using Skeletons,Provides a cen

24、tralized location for design data Simplifies assembly creation / visualization Aids in assembling mechanisms Minimizes unwanted parent-child relationships Allows you to assemble components in any order Controls propagation of external references,Central source for information,Benefits of Communicati

25、ng Information From a Central Source Task distribution Concurrent Modeling Managing External References Tools Declaration Publish Geometry Copy Geometry,Hierarchy,Top_level.asm Top_level_skeleton.prt Sub_assy_1.asm Sub_assy_1_skeleton.prt Sub_assy_2.asm Sub_assy_2_skeleton.prt Sub_assy_x.asm Sub_ass

26、y_x_skeleton.prt,3D Design Finally!,The foundation is set but topologically modifiable its time for 3D. With Reference Control Manager, you are safe to create your parts directly in the assembly.,More Than Meets The Eye!,Interchangeability: Family of Tables Interchange Assembly Layout Declarations,P

27、ower of Top-Down Design,To Achieve Advanced Automation, consider using: Relations Pro/Program,Miscellaneous Tips,Separate Part Versus Assembly for Skeleton Features Avoid constructing assembly-level skeleton features since the system requires that you perform all edits of these features in Assembly

28、mode. The components can become an obstruction and degrade performance. Furthermore, you cannot easily reuse skeleton features at the assembly level in other subassemblies. By using a separate part file, you can edit the feature in Part Mode and reassemble it into many different assemblies. Geometry

29、 Features Place all static information in a skeleton as early as possible and place all dynamic information later in the design process cycle.,Miscellaneous Tips,Datums for Skeleton Models Consider renaming skeleton datums to “sk_” Visualization Use simplified reps and transparency prolifically to m

30、ake viewing easier Use “display states” to highlight different items at different times Use surfaces to clarify meaning of centerlines & axes Conceptualization Dont be afraid to use simple hand sketches before delving into complex situations its NOT illegal,Pro/E Wildfire EnhancementsHigh-performanc

31、e Assembly Modeling,Lightweight Components Represent common components with lightweight graphics for optimum display speed Accurate mass properties and BOMs Customizable symbolic representations Flexible Components Represent multiple states of a single component in an assembly Addresses critical nee

32、d for consistency between BOM and assembly model Intelligent Regeneration Assembly regeneration is up to 80% Faster!,Highlights of Top-Down Design,Capture knowledge, or design intent, allowing you to concentrate on significant issues by making the software perform tedious, repetitive calculations. E

33、nable the framework for interchangeability of components allowing for high-velocity product development by supporting rapid iterations of product variations. Create a concurrent design environment by spreading project design responsibility across many organizational levels.,New in Advanced Assembly in Wildfire 3.0,Data Sharing Dashboard The Data Sharing dashboard consolidates the Merge, Cutout, and Inheritance features in a modern user interface. Enhancements to Data