Digital Twin for Variation Management: A General Framework and Identification of Industrial Challenges Related to the Implementation

Abstract

Digital twins have gained a lot of interest in recent years. This paper presents a survey among researchers and engineers with expertise in variation management confirming the interest of digital twins in this area. The survey shows, however, a gap between future research interest in academia and industry, identifying a larger need in industry. This indicates that there are some barriers in the industry to overcome before the benefits of a digital twin for variation management and geometry assurance can be fully capitalized on in an industrial context. To identify those barriers and challenges, an extensive interview study with engineers from eight different companies in the manufacturing sectors was accomplished. The analysis identifies industrial challenges in the areas of system-level, simulation working process, management issues, and education. One of the main challenges is to keep the 3D models fully updated, including keeping track of changes during the product development process and also feedback changes during full production to the development engineers. This is a part of what is called the digital thread, which is also addressed in this paper.

Exploring the Potential of Digital Twin-Driven Design of Aero-Engine Structures

“…Numerous issues with implementing DTs in industry has been identified. Wärmefjord et al, 2020 reports that, among other problems, companies tend not to update product models with real geometrical data, and that design engineers often lack access to production inspection data. Furthermore, as the concept of DT still is in its early stages there is no standardized way of how to model one .…”

Tolerancing Informatics: Towards Automatic Tolerancing Information Processing in Geometrical Variations Management

“…Beside this, sophisticated tolerance and variation simulation tools in the form of digital twins for geometrical variations management, such as those presented in [15] based on fundamental concepts of standards for the geometrical product specification and verification or as proposed in [16], are important enablers for tolerancing informatics workflows. This is because they allow the modelling and processing of instantiated part variation information in real-time and thus enable the realization of smart assembly and advanced matching strategies [17].…”

“…However, the implementation of a digital twin for geometry assurance still entails some challenges in industry [17].…”

Can ISO GPS and ASME Tolerancing Systems Define the Same Functional Requirements?

“…Manufacturing metrology covers verification of whether produced parts fulfil functional requirements defined by a customer. A designer transforms functional requirements into dimensional and geometrical tolerances that limit actual part deviations and determine a part's performance [1,2]. For example, roundness deviations and dimensional deviations of bearings and their adjacent components (shaft and housing) determine a cylindrical roller bearing's vibrational behaviour and fatigue life [3].…”

“…It should be noted that transformation from ASME Y14.5 to the ISO GPS notation without loss of the part's intended function (loss of coded information) may be performed in a significantly larger amount of cases than reverse conversion due to a new set of modifiers implemented in ISO 1101:2017 [7]. It was underlined in [2] that ISO 1101:2017 allows for more precise tolerance definitions that are independent of the view plane and also support digital threads for geometry assurance. One hundred and fifty ISO documents [5] currently form the ISO GPS system, but only about ten devoted to geometrical tolerancing are directly addressed to designers, manufacturers and quality staff involved in product development and production.…”