Tech Transfer Licensing
CAD/CAM Design Methodologies
Frequently Asked Questions About the Delphi Design Methodologies (DDM)
Why is Delphi making their Lean Design Methodologies available?
Delphi has demonstrated that the LDM work. We save time and money every day and pass these savings along to our customers. We would also like our suppliers to benefit from the cost and cycle time savings we have realized, so we decided to make the LDM available to all manufacturers. Our service providers, experts in CAD training and best practices, provide training, consulting and certification for the LDM and we share in these revenues. However, the real benefits accrue to Delphi when every US manufacturer operates at maximum efficiency – that's when we all win. The LDM are one way Delphi can help us all reach this goal.
How do you implement methodologies like the LDM in an organization?
At the beginning of our presentation we emphasized the importance of standardized methodologies. The best way to think of the LDM is in the same way Six Sigma and CM-II and other standardized methodologies and best practices are used. The LDM, like other standardized methodologies, should be implemented globally throughout your organization, on a program-by-program basis. We found it convenient and effective to implement training on new methodologies when new versions of CAD systems are implemented, for example, when programs migrate from CATIA V4 to V5. In addition, any time a new person joins our CAD team he or she learns the LDM. We have found this to be a very effective deployment strategy. The people involved in any new methodology are very important. Here at Delphi, we have had early adopters of the LDM whom recognized the benefits of using the new methodologies and have helped standardize and proliferate them to others. As you might expect, some of our highly experienced designers were slower to adopt the LDM, but we found that when they saw the increased project throughput and general success of the LDM users, even these experienced designers migrated to the LDM. When people see how quickly changes can be made and designs updated, then adoption by all became "contagious" and the LDM moved very quickly through our design community. Today, we occasionally audit CAD files to check adherence to the standards, but variances are rare. Everyone understands the value of applying the standards correctly.
How, specifically, do the LDM standardized methodologies help global collaboration and improve cycle times?
Many ways. The LDM help give us complete control over a single, fully associative master model. Whether we use that master model at Saginaw, Poland, Spain or anywhere else in our engineering factory, the 3D CAD model drives the master model that drives all documentation. The LDM provide several ways to enhance cycle time. We have the ability to perform virtual prototyping and to simulate the manufacturing process before we actually produce parts. Using master process models and the LDM, we have the ability to use our processes in worldwide sites accommodating differences in culture and local work conditions. Local production operations can make its own decisions about the most efficient manufacturing processes and easily change machine sequences to implement the new process. The LDM also insure that all the data stays fully associated in a single CAD file, and that all documentation derives from this single master model. This allows us to bring products to market faster than our competitors and save money. These are some of the examples of how using these methodologies have benefited Delphi and our customers. We believe these methodologies can be a useful tool in your organization as well.
Our experienced designers sometimes use datum planes in design. What is unique about the LDM?
Before standardizing the LDM, we had as many "best practices" as we had designers. Under these circumstances it became very difficult to share files since the work was not uniform. What we did in developing the LDM was listen to our experts, adopt the best ideas, and create a standardized approach to design using what amounts to a common language.
Delphi produces many new or revised products each year. In order to put the LDM into production, the methods had to be fully tested on the vast array of combinations and special cases. All of these experiences are built in to our standardized methods. This is the unique aspect of the LDM.
How do the LDM help in processing change orders faster?
When engineering revisions are submitted to the design group, the designer assigned to these revisions can make the specified changes with greater speed because:
- the CAD models don't break when they are modified, due to the absence of parent child relationships in the CAD model; and
- the designers use standardized methods when creating the product and process design, so other designers can easily recognize their design intent and better understand critical aspects of the design.
Significant advantages to this are:
- greater flexibility being allowed in selecting the designer having the lightest workload or being best suited to implement the design requirements;
- having the ability to delete design or manufacturing features, or move them to any location within the model, without negative impact; and
- having a single, fully associative model connecting the original CAD model with process models and all the final drawings, thereby identifying any potentially negative affects of changes instantly, even in far-away production facilities, which saves time and cost.
Thus, the LDM leads to a smoother workflow through the design group while ensuring the integrity of the model data. CAD models no longer must be created by the original designer, because the LDM are easy to understand and forgiving enough to allow for personal design skills and preferences.
LDM Enforcement Standards: How have you verified that each of your designers are following these design standards? Does your checking process include a verification of the 3D CAD model?
Yes, Delphi uses a verification process to ensure that all designers use the LDM Methods. We randomly audit designs to ensure that everyone follows the LDM best practices. Since the product model structure is simple and readily apparent, we allow different designers to work on each other's models, when the demands of the workplace dictate. Since everyone understands LDM and the value of standardized methodologies (to both their own job and the company), our modelers self-police or automatically correct design inconsistencies.
Modeling Speed: How do you reduce modeling time by 20% on the basic building of models? Are fewer clicks involved?
The 20% reduction in time to create models number can be looked at in two ways. First, when a model is being developed, its design direction cannot be fully determined at the beginning. The evolution of the model can take many directional changes before it is considered complete. The flexibility inherent in the LDM ensures that the maximum amount of the work a designer has already done is value-added work. Second, the LDM enhance any revisions to existing work due to the absence of feature dependencies. The insertion of any new features at any point in the feature tree, or the deletion of existing features therefrom, can be accomplished without a negative impact.
Pro/E Capability: Do the LDM work with Pro/E?
The LDM work in the Pro/E environment. We have fully tested Horizontal Modeling methodology in Pro/E and confirm and certify its operation. We continue to test Digital Process Design in the Pro/E environment and when fully tested and confirmed, we will announce this to the MCAD community.
Legacy Data: How and when do you convert legacy data from vertical features trees into LDM?
There are several strategies we employ to handle legacy data. We have standard methodologies, taught as part of LDM training, to convert existing models (legacy) into the LDM format. If such legacy data is deemed important, such as for an often-used seed file application, we will convert that data immediately. However, prior to converting a legacy file, we ensure that all features are controlled using parameters. Since the LDM enhance the use of parameters, such conversion allows the full power of the LDM to be used.
Assemblies: Have the LDM techniques been used to create assembly models?
It is important to remember that the LDM comprise the best practices for product and process modeling – essentially the "headwaters" of the manufacturing process. In developing these Methodologies, we tested and confirmed that the LDM are indeed fully compatible with assemblies. Each year, Delphi produces thousands of parts using the LDM, including assemblies. We would have abandoned the LDM years ago if they were not compatible with assemblies.
CAD Tools: Do you have to rely on third-party software vendors to provide their CAD tools in order to use the LDM? Are the LDM specific to your manufacturing environment or can all CAD/CAM users use them generally?
It is important to remember that the LDM employ NO new software. The only requirement to implement the LDM is learning the Methodologies. The LDM's standardized LDMtechniques apply to all major CAD platforms, and to date we have certified their operation in CATIA, UG, and Solidworks platforms. As noted above, testing and certifying the LDM in the Pro/E platform have been completed for Horizontal Modeling, and testing is currently in progress to confirm operation of Digital Process Design in Pro/E. LDM.
Engineering Changes: Do you require model changes to be approved by a Change Review Board?
Yes. We require that all document changes be approved by a Change Review Board. We use the CMII system as our standardized methodology for configuration management across our global organization. This process requires a formal review of all changes by the respective Change Review Board for each product line. The emphases of CMII are accommodating change, optimizing the reuse of best practices, such as the LDM, and assuring that all requirements are clear, concise, and valid. The LDM enhance the CMII process by allowing us to process changes faster as a result of increased designer efficiency and CAD model flexibility. In addition, our use of the LDM has lead to improved quality of documentation regarding associated product and process models.