320d37f2fc35b65af08cef6451a15f19.ppt
- Количество слайдов: 54
Introduction to PDM and PLM PDM is the management and classification of design data and specifications for an engineered product, and the management of change to this information. PLM is the activity of managing a company’s products all the way across their lifecycles in the most effective way. [Stark] PLM system is [an information system] that facilitates all or some subset of PLM activities. [Stark]
Background: what are lifecycle activities? - Product Realization: from concept to production - Production: supply chain coordination - After-sales: service, maintenance, product updates, obsolescence management…
Background: Product Realization Process Earlier we saw a PRP flowchart Some crucial elements of PRP: - many decisions are made whose rationale must be remembered - large amount of data is generated, most is persistent Some questions: - how can we reduce the effort/time of data creation - how do we manage the project schedule - what is a good way to store the “knowledge learnt”
Background: Supply Chain Coordination A fundamental data-set created during the PRP is the Bill of materials (BOM) - What is the relationship of BOM with MPS ? PRP involves sourcing/procurement vendor management. - What are the potential effects of vendor mis-management on the company? -- different quality specs from different sources -- different prices, lead times, …
Background: After-sales Service -- Service manuals are usually created at the end of PRP (often poorly!) Maintenance, product updates -- How many Windows™ updates have you received this month ? Obsolescence management -- Until what year must a company provide spare parts for a product? ** Will Mazda provide a spare side-mirror for the 1987 RX-7? ** Will a Canon EF-S lens work with the next Digital SLR?
Implications of these issues (1) Large amount of information to manage A systematic method for information management A method/strategy that reduces data is better* A method to reduce effort in information management Integration of data management (2) There a lot of activities, many are concurrent Mechanism to manage and optimize activities [project management, scheduling for optimal makespan]
Historical view of Product Lifecycle Management >150 years ago: Designer managed product data (drawings etc. ), Only the designer could understand this data… Leonardo Da Vinci’s Ornithaptor (flying machine)
Historical view of PLM. . ~100 years ago The Drawing Board : Engineers could communicate using a common language, Engineering Drawings
Historical view of PLM. . . ~30 years ago The computer: 2 D becomes precise and modifications are easy… 2 D CAD
Historical view of PLM…. But… Problems with 2 D CAD -- 2 D does not represent the reality -- 2 D cannot model surfaces & solids -- 2 D is subject to misinterpretation
Historical view of PLM…. . ~1985 3 D CAD: allows defining complex parts and assemblies
Historical view of PLM…. . . ~1990: 3 D CAD allows automatic generation of CNC data (to machine the part) Define Tool CNC data Make 3 D model Simulate cutting
Historical view of PLM……. ~1995 3 D CAD: allows analysis
Historical view of PLM……. . But here is the difficulty (1) Products are assemblies of many parts. . Automobiles: > 10 000 parts Ships: > 1 000 parts (2) Assemblies are created by many concurrent designers and enterprises Need for collaboration, concurrent design in separate locations
Historical view of PLM……… ~1995 Digital Mockup (DMU) replaces physical prototypes Boeing 777: • First jetliner to be 100 percent digitally designed using 3 D CAD • > 3 million parts, > 900 suppliers from 17 countries • Max alignment error on the first 777 was 0. 023” (other planes: ~0. 5”)
Historical view of PLM………. Digital mock-up is an alternative to constructing physical prototypes Functions of DMU: 1. Complete 3 D visualization of a product 2. Collaboration tool – since all engineers can see (partial) assemblies as the components are designed by different members of the team 3. Assembly analysis - tests if some components are intersecting (design error) on assembly - allows simulation of the functioning of the product (kinematic) - allows testing of dynamic stresses (including Finite Element Analysis)
Historical view of PLM………… ~2000 Product Lifecycle Management (PLM) extends the scope of DMU Upstream - Design Adherence to Requirements & Regulations - Validation and Certification Process - Optimal Re-Use of Corporate Assets - Impact of Requirements Changes on Project Schedule Downstream - Manufacturing - Plant design & simulation
Historical view of PLM …………. ~2000: Knowledge-Based CAD to support collaboration: Store the know-how share design rules
Knowledge-Based CAD In the beginning: there were 2 D blueprints, physical prototypes Knowledge minds of the engineers/managers/technicians Levels of KBE: parametric design variational design catalog-based design rules-governed design
Parametric designs Traditional design: geometry is dimensioned with constants (e. g. length) Parametric design: dimensions are in form of variable = expressions expression: constant, or an algebraic formula R=X B= Y Y X = max(5, 0. 1 L) D = 0. 5 H H L What are the independent variables and the dependent variables?
Parametric designs: an example sun is bigger Non-parametric design: Suppose the sun increases in size Sun gets chopped off at top; book gets cut by the sun
Parametric designs: example. . sun is bigger L L’ Parametric design: Geometric relation between center of sun, radius of sun, and top of book Geometric relation between length of part and size of sun
Parametric design examples 4 x counterbored holes, depth = thickness of flange/3 (5) By convention, derived dimensions are shown in parenthesis by many CAD systems.
Parametric design examples Definition of a nut Length of threads Length of smooth part = total length – threaded length
Parametric design examples Components that mate with each other (most products are assemblies) - Dimensions on mating parts are parametrically related. Advantage: Design modifications in one part will automatically propagate the change in all related parts.
Parametric design examples. . Exploded view: Yamaha YFM 200 Motorcycle Automatic Clutch
Catalog-based Designs An extended of parametric design: Base model specifies topology and relations between geometry The design details are all expressed as parameters Part design is created by providing a table with parameter values Standard sections Al extrusions …
Catalog-based Designs: an example Catalog of fasteners (screws, nuts, …)
Catalog design We shall assume a catalog of parts (though you can have product catalogs) 1. Divide the group of products into categories; each category has the same set of descriptors 2. Each group will form a sub-set of the catalog, called family e. g. Fastener chapter, Screw family, has attributes: designation, type, dia, length 3. Construct a parametric CAD model of one member of the family QUESTION: What are the independent variables in this model? 4. Identify the independent variables with names matching attribute names
Catalog design… 4. Identify the independent variables with names matching attribute names 5. Create a table (e. g. a MS Excel table) with attributes and values 6. Use the GUI of the CAD system to link the table, design, family description
Catalog-based Designs Using catalogs: Catalogs ≈ a Database table search for a catalog component using a query on its design parameter(s) Example Filter: (l_length > 10) and (l_length < 15) Alternate method: Most CAD systems will allow a thumbnail preview and select
Rules-governed design Rules are a mechanism to add design knowledge Examples of design knowledge: 1. Standard design knowledge 2. Manufacturability knowledge (specific to a company) 3. Design guidelines (specific to a company) 4. Compliance rules …
Rules-governed design Standard design knowledge Example: design of a latch in a plastic component From theoretical solid mechanics Stress = E e [E is Young’s modulus of the material] We must ensure that stress = E 3 Yh 0/2 L 2 < fracture stress = smax DESIGN RULE: 3 EYh 0/2 L 2 < smax
Rules-governed design Manufacturability knowledge Background for this example: Common features in plastics components These features are constructed using standard operations in CAD systems Rib operator in CATIA Rib operator in Solid. Works
Rules-governed design Manufacturability knowledge Experience from injection molding: rib thickness > 0. 5 t t Inferred design guidelines: ACTION: rule is set up in the CAD system; violation triggers a warning
Product instantiation For a well-defined product architecture, the Product Instance is generated by the following steps: 1. Basic assembly model of a template product of the family is retrieved 2. All components that will be used are retained, others are discarded 3. Parameter values for each template part are set 4. New components are designed (using catalogs if possible) 5. Design rules are applied
Digital Mock-Up (DMU) Constructing a DMU 1. Part designs of all components are stored in a DB 2. Define the product structure as a BOM (BOM can access the DB) 3. The parts are assembled – note that this assembly definition is richer than classical assembly in CAD (it needs to store kinematics)
DMU Examples: Shipman™ Mock up of boat design to test ergonomics of spaces for humans
DMU Examples DMU allows for accessibility testing in aircraft design (for repair/maintenance)
Collaboration (through DMU) DMU improves collaborative function because: 1. Parts that are being constructed by different designers get loaded into the DB, and associated with the product structure. 2. Each part that is put into the DMU must be “put-in-place” – namely its spatial relation with other parts already in the system must be defined. 3. It follows that the entire team can see how the product is getting constructed in real-time.
Definitions (re-visit) PDM is the management and classification of design data and specifications for an engineered product, and the management of change to this information. PLM is the activity of managing a company’s products all the way across their lifecycles in the most effective way. [Stark] PLM system is [an information system] that facilitates all or some subset of PLM activities. [Stark]
Product Lifecycle Management CAE Tooling design CAD Item management Product structure centralized DB [File vault] Security Engineering Changes Task management “Item” could be: • CAD document • Text document • Design spreadsheet • Software program • Process Plan • SOP • Customer complaint • Service records
Product Lifecycle Management Item management - product architecture planning Product structure - specification (BOM tree, hierarchical model) - Instantiation (parametric) from templates centralized DB [File vault] Security Engineering Changes Task management
Product Lifecycle Management Item management Product structure centralized DB [File vault] Security Engineering Changes Task management - Authority - Views - Access control (check-in/check-out)
Product Lifecycle Management Item management Product structure centralized DB [File vault] Security Engineering Changes Task management -ECR - Design modifications - Confirmation/approval cycle - ECN - Info storage/retrieval
Product Lifecycle Management Item management Product structure centralized DB [File vault] Security Engineering Changes Task management -team specification (requirement based, resource based) - task assignments - milestones setting, management - critical path - deadline reminders, notifications
PLM functionality PLM supports 3 levels of collaboration
Potential Benefits of Product Lifecycle Management Reduced Time-to-Market Improved Design Productivity Improved Concurrent Engineering Improved Design and Manufacturing Accuracy Data Integrity Safeguarded Better Project Planning Better Management of Engineering Change
Industry adaptations Hewlett-Packard Co. uses Windchill™ from PTC: -- achieved 80% improvement in design and process reuse. -- They reduced time-to-market, product cost, and warranty cost. NEC computers uses Agile Product Collaboration solution suite: -- 30% savings in monthly engineering workload; -- 39% reduction in scrap and rework costs. Rockwell Automation uses Teamcenter from UGS PLM: -- Manage the engineering change notice system; -- 50% reduction in ECN cycle time -- Save US$200 per ECN [total savings: US$ 400, 000 in one business unit ]
Perspectives on adaptation of PLM NECESSITY - companies that are part of global supply chain or design chain need collaboration tools MARKETING - companies with short mean-time-between-upgrades, e. g. computer manufacturers SECURITY - Example 1: e. Commerce collaboration between potential client and designer - Example 2: Software/hardware security (e. g. Microsoft windows updates)
Perspectives on adaptation of PLM. . MARKETING - firmware upgrades on digital cameras, mp 3 players; where the company captures market by an early release, and later upgrades functionality PRODUCT STRATEGY - Mass customization and modular product design companies need efficient product architectures to allow part/process reuse over generations GREEN - companies responsible for recycling of their sold products e. g. printer toner cartridges, aluminum cans, plastic or glass bottles, paper
Perspectives on adaptation of PLM… SERVICE - companies with long-life products, that need continued repair, service etc. e. g. automobiles. 1. spare parts for older models must be available 2. service manuals 3. testing equipment, e. g. testing onboard computers and microprocessors, must be maintained 4. Management of product recalls Ford Explorer, Firestone [2000 -2001]: Replaced 13 million tires. Nissan motor [2003]: 2. 55 million cars recalled to fix engine defects; Cost: JPY 15 billion.
Commercial PLM systems Parametric Technologies (Pro/Engineer): Windchill Dassault-IBM (CATIA, Solidworks): Smar. Team Unigraphics + SDRC (UG, I-DEAS): Teamcenter+Metaphase Autodesk: Autodesk Vault+Autodesk productstream+…
Summary PLM: Information system integrating Product Design + Knowledge-based CAD Collaboration Document control Workflow management Engineering change management