Abstract
Keywords
Body, PLM, practices, methods, CAD, VPDM
Abstract
Every carmaker wants to optimize its Body process chain to dramatically reduce the time between "Styling Freeze" and "SOP" (Start of Production). In order to reach this objective, the overall design process needs to be reengineered to allow simultaneous engineering, fast design change, and seamless processes from the early-styling idea stage right through to manufacturing definition.
The BiW process has been transformed over the past years through different practices, from the drawing board, to 2D CAD*, to 3D CAD, and then to Digital Mock-up (DMU). Despite the progress, most of the CAD models include very little product
Knowledge and hence cannot be reused from one car program to the next. Dassault Systèmes PLM technology and Practices, on the other hand, enable car manufacturers to reuse existing design data and achieve their objective of significantly reducing development cycle time. These Practices include:
(1) "Advanced Part Design"
The technology behind these new BiW practices, called "Specification Driven Modeling", was created in the 90s. It involves capturing the surface history and requires BiW designers to become CAD experts responsible for creating reusable "templates" for other car programs. As of today, several car manufacturers have already achieved "advanced part design" with CATIA® V5 on BiW production components with benefits up to 80% for a typical exterior styling surfaces change.
(2) "Relational Design"
A car body consists of approximately 350 components that are mainly driven either by exterior surfaces or packaging/ergonomics constraints. Styling changes can have major repercussions that need to be analyzed and performed very quickly. This distribution and synchronization of work is possible only by using technological links between all these models (Styling, Packaging, BiW components, etc.). ENOVIA® products, used at several car manufacturers, manage the lifecycle of these components and the change process to make Relational Design a reality. Expected benefits of this practice is a 45% reduction of the total BiW design cost on a given car platform.
(3) "System Design"
Car manufacturers are currently implementing the first two practices to speed up design, however, there are still remaining issues after "Styling Freeze" that lead to heavy costs (e.g. stamping die modifications). The only way to solve most of these issues upfront is to adopt a "system" approach versus a "component" approach. This new practice is possible only if a major organizational change takes place so that CAD designers are no longer responsible for delivering components but rather for delivering systems.
(4) Process Chain Integration (CATIA/ENOVIA/DELMIA) Manufacturing departments want to participate in the design of the car body early on in the product creation process (Manufacturing Driven Engineering). Developing 3D components in the early phase of a car program helps manufacturing to start earlier. Thanks to the DS PLM architecture and technology, Process and Resources will be "associative" to the Product change.
Due to Dassault Systèmes long experience with car manufacturers, these Best Practices have been capitalized and can be smoothly introduced to BiW Engineering teams by using a "consulting" approach based on three phases:
(1) Share the Best Practices (Objectives, Metrics)
(2) Analyze the current processes and design the Company Best Practices (Roadmap,Methods definition)
(3) Deploy these Best Practices (Training, Support, Benefit measurement).