Additive Manufacturing of Certified Aircraft Interior Components
Creators: name: Senanayake, Pruthvi Akesh
Publisher: name: RMIT University
Year: 2024
Subjects: classificationCode: 401408
subject: Manufacturing processes and technologies (excl. textiles)
classificationCode: 401403
subject: Flexible manufacturing systems

description: This PhD presents a novel and comprehensive study on an end-to-end methodology for rapid on-demand design and production of aircraft interior replacement parts. The objective of the methodology is to ensure a rapid turnaround for replacement parts, which is currently a critical challenge faced by aircraft operators due to significant costs from replacement parts being unavailable or requiring extensive lead times. Additionally, the high variability and bespoke nature of aircraft interiors necessitate a flexible and on-demand approach.
Additive manufacturing emerges as the ideal production form for this methodology due to its rapid nature and manufacturing flexibility. This study showcases the utilisation of an additive manufacturing production system, exemplified by the “Aircraft Interiors Certification Solution” developed by Stratasys, explicitly tailored for certified aircraft interior parts. To underscore the real-world applicability, two case studies, including an aircraft seat armrest cover and tray table, are used for development and validation purposes throughout the study.
A detailed literature review is presented, which covers a range of multidisciplinary topics relevant to the study. The lack of research on a methodology for rapid on-demand design and production of aircraft replacement parts is highlighted. Additional gaps and challenges considered in this study include designing parts remotely without access to original part data or high-end data capture equipment. 
The end-to-end methodology is developed, which entails establishing the key processes, components, characteristics, and stakeholders. The key processes, including geometry capture, re-engineering, certification, and production, are integrated into a high-level framework and refined into a detailed and structured methodology. Furthermore, the incorporation of additive manufacturing is complemented by the integration of knowledge-based engineering and Industry 4.0 technologies, such as model-based systems engineering and digital twin methods, to support a rapid and on-demand methodology.
The critical relationships of the methodology are meticulously investigated to establish the dependencies between the components of the methodology and the flow of information from end to end. A novel geometry capture method is developed that is tailored to remote access and the resources available in an aircraft maintenance context. Key areas investigated for relationships include geometry capture, certification, and operations. Establishing critical relationships ensures optimal and efficient utilisation of the methodology while providing a holistic and comprehensive outlook.
The performance of the methodology is assessed using time as the key performance indicator, which is crucial for ensuring a rapid turnaround. Performance measurement is conducted in terms of the elapsed time, with results showing approximate lead times of 22 hours for simple interior parts and 47 hours for complex interiors. The methodology is shown to outperform traditional manufacturing by reducing lead time by up to 68% using conservative estimation approaches.
Additionally, the performance parameters of the methodology and their impact are also established. A total of 6 parameters that relate to the operational conditions of the methodology and 20 parameters relating to the design of the interior part are identified. The design-based parameters are grouped into five distinct categories, which are shown to have a significant impact on the elapsed time of the methodology, with the printing volume category contributing over 50% relative to the other four categories. Performance management aspects are also highlighted, which demonstrate how various strategies and techniques can be used to enhance or maintain the performance of the methodology.
This PhD offers significant novel contributions to literature by addressing key research gaps and developing solutions tailored to the aircraft industry. The development of a rapid on-demand methodology for the design and production of aircraft interior replacement parts serves to minimise the unavailability of replacement parts and any associated costs for operators. Ultimately, this methodology fosters continuous and sustainable aircraft operations. Moreover, this research extends beyond immediate benefits, where broader outcomes include, but are not limited to, facilitating the expanded utilisation of additive manufacturing within the aircraft industry, enabling accelerated certification processes, and opening avenues for applying this methodology to primary and secondary aircraft parts.