Product Lifecycle Management
Product Lifecycle Management or PLM is a term used for the process of managing the entire lifecycle of a product from its conception, through design and manufacture to service and disposal. PLM is a set of capabilities that enable an enterprise to effectively and efficiently innovate and manage its products and related services throughout the entire business lifecycle. It is one of the four cornerstones of a corporation's IT digital structure. All companies need to manage communications and information with its customers (CRM-Customer Relationship Management) and its suppliers (SCM-Supply chain management) and the resources within the enterprise (ERP-Enterprise resource planning). In addition, manufacturing engineering companies must also develop, describe, manage and communicate information about their products (PLM).
Documented benefits include:
- Reduced time to market
- Improved product quality
- Reduced prototyping costs
- Savings through the re-use of original data
- A framework for product optimization
- Reduced waste
- Savings through the complete integration of engineering workflows Contents
Introduction to development process
The core of PLM is in the central management of all product data and the technology used to access this information and knowledge. Although PLM as a discipline emerged from tools such as CAD/CAM and PDM it must be viewed as the integration of these tools with methods, people and the processes through all stages of a product£ªs life.
For simplicity the stages described are shown in a traditional sequential engineering workflow. The exact order of event and tasks will vary according to the product and industry in question but the main process are:
- Concept design
- Detailed design
- Validation and analyse(simulation)
- Tool design
- Manufacturing Planning
- Test (quality check)
- Sale and Deliver
- Maintain and Support
The major key point events are:
- Design freeze
The reality is however more complex, people and departments cannot perform their tasks in isolation and one activity cannot simply finish and the next activity start. Design is an iterative process, often designs need to be modified due to manufacturing constrains or conflicting requirements. Where exactly a customer order fits into the time line depends on the industry type, whether the products are for example Build to Order, Engineer to Order, or Assemble to Order.
Phases of Product Lifecycle and corresponding technologies
Many software solutions have been developed to organize and integrate the different phases of a product£ªs lifecycle. PLM should not be seen as a single software product but a collection of software tools and working methods integrated together to address either single stages of the lifecycle or connect different tasks or manage the whole process. Some software providers cover the whole PLM range while others a single niche application. Some applications can span many fields of PLM with different modules within the same data model. An overview of the fields within PLM is covered here. It should be noted however that the simple classifications do not always fit exactly, many areas overlap and many software products cover more that one area or do not fit easily into one category. It should also not be forgotten that one of the main goals of PLM is to collect knowledge that can be reused for other projects and to coordinate simultaneous concurrent development of many products. It is about business processes, people and methods as much as software application solutions. Although PLM is mainly associated with engineering tasks it also involves marketing activities such as Product Portfolio Management (PPM), particularly with regards to New product introduction (NPI).
Phase: 1. Conceive
Imagine, Specify, Plan, Innovate
The first stage in the development of a product idea is the definition of its requirements based on customer, company, market and regulatory bodies£ª viewpoints. From this a specification of the products major technical parameters can be defined. Although often this task is carried out using standard office software packages there are for the field of Requirements Management a number of specialized software tools available. Parallel to the requirements specification the initial concept design work is carried out defining the visual aesthetics of the product together with its main functional aspects. For the Industrial Design, Styling, work many different medias are used from pencil and paper, clay models to 3D CAID Computer-aided industrial design software.
Phase: 2. Design
Describe, Define, Develop, Test, Analyze and Validate
This is where the detailed design and development of the product£ªs form starts, progressing to prototype testing, through pilot release to full product launch. It can also involve redesign and ramp for improvement to existing products. The main tool used for design and development is CAD Computer-aided design. This can be simple 2D Drawing / Drafting or 3D Parametric Feature Based Solid/Surface Modeling, Such software includes technology such as Hybrid Modeling, Reverse Engineering, KBE (Knowledge Based Engineering), Assembly construction. It covers many engineering disciplines including: Mechanical; Electrical; Electronic and Architectural. Along with the actual creation of geometry there is the analysis of the components and product assemblies. Simulation, validation and optimization tasks are carried out using CAE (Computer-aided engineering) software either integrated in the CAD package or stand-alone. These are used to perform tasks such as:- Stress analysis, FEA(Finite Element Analysis); Kinematics; Computational fluid dynamics (CFD); and mechanical event simulation (MES). CAQ (Computer-aided quality) is used for tasks such as Dimensional Tolerance (engineering) Analysis. Another task performed at this stage is the sourcing of bought out components, possibly with the aid of Procurement systems.
Phase: 3. Realize
Manufacture, Make, Build, Produce, Sale and Deliver
Once the design of the product£ªs components is complete the method of manufacturing is defined. This includes CAD tasks such as tool design; creation of CNC Machining instructions for the product£ªs parts as well as tools to manufacture those parts, using integrated or separate CAM Computer-aided manufacturing software. This will also involve analysis tools for process simulation for operations such as casting, molding, and die press forming. Once the manufacturing method has been identified MPM Ã¿ (Manufacturing Process Management) comes into play. This involves CAPE (Computer-aided Production Engineering) or CAP/CAPP Ã¿ (Production Planning) tools for carrying out Factory, Plant and Facility Layout and Production Simulation. For example: Press-Line Simulation; and Industrial Ergonomics; as well as tool selection management. Once components are manufactured their geometrical form and size can be check against the original CAD data with the use of Computer Aided Inspection equipment and software. Parallel to the engineering tasks, sales product configuration and marketing documentation work will be taking place. This could include transferring engineering data (geometry and part list data) to a web based sales configurator and other Desktop Publishing systems.
Phase: 4. Service
Use, Operate, Maintain, Support, Sustain, Phase-out, Retire, Recycle and Disposal
The final phase of the lifecycle involves managing of in service information. Providing customers and service engineers with support information for repair and maintenance as well as (waste management/recycling information. This involves using such tools as Maintenance, Repair and Overhaul Management ( MRO) software.
All Phases: Product Lifecycle
Communicate, Manage and Collaborate
None of the above phases can be seen in isolation. In reality a project does not run sequentially or in isolation of other product development projects. Information is flowing between different people and systems. A major part of PLM is the co-ordination of and management of product definition data. This includes managing engineering changes and release status of components; configuration product variations; document management; planning project resources and timescale and risk assessment.
For these tasks graphical, text and metadata such as product BOMs (Bill of Materials) needs to be managed. At the engineering departments level this is the domain of PDM Ã¿ (Product Data Management) software, at the corporate level EDM (Enterprise Data Management) software, these two definitions tend to blur however but it is typical to see two or more data management systems within an organization. These systems are also linked to other corporate systems such as SCM, CRM, and ERM. Associated with these system are Project Management Systems for Project/Program Planning.
This central role is covered by numerous Collaborative Product Development tools which run throughout the whole lifecycle and across organizations. This requires many technology tools in the areas of Conferencing, Data Sharing and Data Translation. The field being Product visualization which includes technologies such as DMU ( Digital Mock-Up), Immersive Virtual Digital prototyping (Virtual reality) and Photo realistic Imaging.
Product Development processes and methodologies
A number of established methodologies have be adopted by PLM and been further advanced. Together with PLM digital engineering techniques, they have been advanced to meet company goals such as reduced time to market and lower production costs. Reducing lead times is a major factor as getting a product to market quicker than the competition will help with higher revenue and profit margins and increase market share.
These techniques include:- Concurrent engineering workflow Bottom-up design Top-down design Front loading design workflow Design in context Modular design. NPD New product development DFSS Design for Six Sigma DFMA Design for manufacture / assembly Digital simulation engineering. Requirement driven design Specification managed validation
Concurrent engineering workflow
This is a workflow that instead of working sequentially through the stages a number of tasks is carried out in parallel. For example starting tool design before the detailed design of the product is finished; or the engineer started on detail design solid models before the concept design surfaces models are complete. Although this does not necessarily reduce the amount of manpower required for a project it does drastically reduce lead times and thus time to market. Feature based CAD systems have for many years allowed the simultaneous work on 3D solid model and the 2D drawing by means of 2 separate files with the drawing looking at the data in the model, when the model changes the drawing will associatively update. Some CAD packages also allow associative copying of geometry between files. This allows, for example, the copying of a part design into the files used by the tooling designer. The manufacturing engineer can then start work on tools before the final design freeze, when a design changes size or shape the tool geometry will then update. Concurrent engineering also has the added benefit of providing better and more immediate communication between departments, reducing costly due to late in the process design changes. It adopts a problem prevention method as compared to the problem solving and re-designing method of traditional sequential engineering.
Bottom-up design is where the definition of 3D models of a product starts with the construction of individual components. These are then virtually brought together in sub-assemblies of more than one level until the full product is digitally defined. This is sometime known as the review structure showing how the product will look like. The BOM contains all of the physical (solid) components; it may (but not also) contain other items required for the final product BOM such as paint, glue, oil and other materials.
Top-down design follows closer the true design process This starts with a layout model, often a simple 2D sketch define basic size and some major defining parameters. Geometry from this is associatively copied down to the next level which represents different sub-systems of the product. The geometry in the sub-systems is then used to define more detail in levels below. Depending on the complexity of the product a number of levels of this assembly are created until the basic definition of components can be identified, such as position and principle dimensions. This information is then associatively copied to component files. In these files the components are detailed; this is where the classic bottom-up assembly starts. The top down assembly is sometime known as a control structure. If a single file is used to define the layout and parameters for the review structure it is often known as a skeleton file.
Front loading design and workflow
Front loading is taking Top down design to the next stage. The complete control structure and review structure as well as downstream data such as drawings, tooling development and CAM models is constructed before the product has been define or a project kick-off has been authorised. These assemblies of files are a template from which a family of products can be constructed. When the decision has been made to go with a new product the parameters of the product are input into the template model and all the associated data is updated. Obviously predefined associative models will not be able to predict all possibilities and will require additional work. The main principle is that a lot of the experimental/investigative work has already been completed. A lot of knowledge is built into these templates to be reused on new products. This does required addition resources ¡ùupfront¡ì but can drastically reduce the time between project kick-off and launch. Such methods do however require organisations changes as a large amount engineering skills are moved into ¡ùoffline¡ì development departments. It can be seen as an analogy to creating concept car to test out new technology for future products, but in this case the work is directly used for the next product generation.
Design in context
Individual components cannot be constructed in isolation. CAD models of components are designed within the context of part or all of the product being developed. This is achieved using assembly modelling techniques. Other components£ª geometry can be seen and referenced within the CAD tool being used. The other components within the sub-assembly, may or may not have been constructed in the same system, their geometry being translated from other CPD formats. Some assembly checking such as DMU is also carried out using Product visualization software.
Major PLM software product vendors
- Aegeanet System
- Autodesk IngTech Corporation
- Dassault Systemes
- NSB Group