Keywords tolerance, analysis, virtual, prototyping, aesthetics
Abstract Many automotive manufacturers are aware of the importance of improving the cosmetic quality of their products and have introduced design processes, such as Craftsmanship (Ford) and QZ (BMW) to improve product quality. Automotive Engineers are required to predict how manufacturing variations will impact the cosmetic (aesthetic) quality of an automobile. This is of particular importance in products such as automobiles where the A-class surfaces will have an importance in the customers perception of the overall quality of the vehicle.
To predict manufacturing variations, Tolerance Analysis is performed on assemblies using a number of software tools such as VSA from EDS and 3-DCS from Dimensional Control Systems. These tools allow engineers to identify potential tolerance problems and their impact on the overall design by generating statistical data in the form of histograms and distribution curves. This data is useful for identifying if the design will meet its dimensional requirements and for conducting worst case and contribution analyses. However, skill is required to interpret the data and it is difficult to visualise what effect these values have on the aesthetic quality of the product. As a result, these processes still rely predominantly on the production of physical prototypes in order to assess the aesthetic impact.
This paper presents research into a prototype system, the Tolerance Analysis Visualisation
Interface (TAVI). TAVI works in conjunction and is interactive within the VITAL system virtual environment reported in (1-5). The aim of TAVI is to enable multi-discipline quality audits where users can interact, in real time, with a realistic digital prototype and relevant tolerance information.
The perceived benefits of such a system include:
Improved aesthetic quality assessment within a style driven design process
Reduced product cost and time to market
- Earlier identification and fixing of mistakes in the design process
- Reduced number of physical prototypes
Improved product quality
- Optimised design results through minimised variation
This paper highlights the need for this interface within the automotive industry and the shortfalls of existing practices and tools have been identified. Through looking at the latest methods of presenting data to users (information visualisation) and conducting analysis within the automotive industry, the prototype TAVI has been developed. The effectiveness of the prototype system has been evaluated through demonstration within industry and recommendations and future developments are made based on these findings.