Aircraft Airframe Shim Modeling for Tight-Tolerance Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production of aircraft airframes faces challenges in achieving precise assembly due to difficulties in producing separate sections with sufficient precision, leading to lengthy and expensive shimming processes, and the need for dedicated assembly fixtures.
Innovation Solution
A method and system that utilize digital modeling and Additive Manufacturing to create shims that fill gaps between airframe components, allowing for precise assembly and reducing the reliance on traditional assembly fixtures by creating digital models of components, shims, and producing them using materials like aluminum, titanium, or plastic.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If separate airframe sections are produced independently, then production flexibility and independence are improved, but assembly precision deteriorates due to gaps between sections
Solution Approach 1:
Digital models of shims are created in advance during the digital assembly process, before physical production. The shims are designed to compensate for dimensional variations and gaps that will exist when separate airframe sections are produced independently. This preliminary digital planning ensures that precision is maintained despite independent production of components.
Solution Approach 2:
Shims are introduced as intermediary elements between airframe sections. These shims act as mediators that fill gaps and accommodate dimensional variations between independently produced sections. The shims enable assembly precision to be achieved even when sections are produced separately with some variation.
2Ease of operation
If traditional assembly fixtures are used, then assembly operations are supported, but production cost and complexity increase due to dedicated fixtures for each process
Solution Approach 1:
A digital model of the assembly fixture is created and used throughout the process. Instead of multiple physical fixtures, a single physical fixture with locators is used in conjunction with a comprehensive digital model. The digital model serves as a virtual copy that provides all necessary assembly information, reducing the need for multiple complex physical fixtures.
Solution Approach 2:
The assembly fixture is designed as a universal platform that can accommodate different airframe sections and components. Rather than creating dedicated fixtures for each specific assembly operation, a single multi-functional fixture with adjustable locators and support elements handles various assembly tasks, reducing overall fixture complexity and cost.
3Manufacturing precision
If tight tolerance bounds are required for airframe assembly, then assembly precision is improved, but production time increases due to lengthy shimming processes
Solution Approach 1:
All shimming requirements are determined in advance during the digital assembly process. The digital model calculates the exact shim dimensions and positions needed to achieve tight tolerances. This preliminary determination eliminates the need for iterative trial-and-error shimming during physical assembly, significantly reducing the time required while maintaining precision.
Solution Approach 2:
The digital model incorporates measurement data from actual component surfaces and provides feedback on the precise shim requirements. This feedback loop allows the system to calculate optimal shim specifications based on actual component variations, ensuring tight tolerances are achieved without requiring multiple adjustment cycles during assembly.
Data Source
AI summary
A method of producing a shim for use in an aircraft airframe (200) comprising: providing a plurality of component parts (202, 204) of the aircraft airframe (200); measuring a surface of each of the component parts (202, 204) and creating a digital models of the component part (202, 204) therefrom; digitally assembling together the digital models of the component parts (202, 204) thereby to produce a digital model (600) of at least part of the aircraft airframe (200); using that digital model (600), creating a digital model of a shim (604), the digital model of the shim (604) filling a gap between at least two digital models of component parts (202, 204) in the digital model (600) of at least part of the aircraft airframe (200); and producing a physical shim using the digital model of the shim (604).