This Call for Proposal is issued as part of Clean Sky 2 Joint Technology Initiative in which several demonstrators will be developed by the industry. 

The call will contribute to the activities in Airframe ITD WP B-4.3.6: SHERLOC (Structural HEalth monitoring, manufacturing and Repair technologies for Life management Of Composite fuselage). The main activities within the SHERLOC project are directed towards two main areas: 

Advanced methodologies and technologies for maintenance/repair and NDI/SHM

Manufacturing and testing for validation and verification

They address, in particular, the improvement of the current advanced technologies and methodologies with the aim to make them ready for the industrialization phase of a new regional aircraft fuselage. 

Sub-component to be manufactured and tested within SHERLOC is a fuselage panel which is composed of skins, stringers and frames; Floor Beam, Pressure Bulkhead, Window Frame and fittings. These components will be sub-assembled with maximum level of integration and reducing assembling work. 

The Partner that will be selected for this Call will be responsible for developing an open source generic software platform to be delivered to the Topic Manager and following technical specifications agreed by the Topic Manager. 

Scope of work

The objective of the call is to develop a multidisciplinary optimization open source software with an included cost model for composite fuselage design, manufacturing, repair and maintenance. The cost model shall include the economic benefit or otherwise of on-board structural health monitoring technologies (SHM) such as Piezoelectric transducers and Fibre optic sensors. The motivation for cost estimation and cost modelling emanates from the desire to economise the future manufacturing costs before or during the product design phase as well as minimizing the costs of maintenance through SHM technologies.

The SHERLOC-Cost-Optimisation open source software (outcome of this call) shall allow for cost estimation and economic comparison of different manufacturing route (e.g. hand layup, automatic tape layup, automatic fibre placement, resign transfer moulding, injection moulding, thermoplastic forming, etc.). The models can be primarily based on detailed cost model estimation method, however, parametric models, mathematically derived are also to be integrated into the software. 

SHERLOC-Cost-Optimisation software shall provide a flexible and transparent cost estimation process with appropriate statistical confidence values. The software shall provide platform to adopting different cost estimation strategies generally adopted within the aeronautics industry, namely: 

Analogous cost estimation (based on actual historical data with cause and effects understood)

Parametric cost estimation (statistical uncertainty of the forecast; allows for scope of quantifying risk)

Bottom-up estimation frame work for all new products and manufacturing routines.

The development of generic cost estimation model utilizing information is of importance as different sub-components have different elements with specific costs attributed to each part. For example, the generic element’s cost attributes may include geometry, material, process and production planning as depicted in Figure 1. The method follows the bottoms up cost estimation approach. 

The software shall include technical cost models that accurately reflect the real production environment to correctly evaluate the business case behind new product development. The cost drivers shall include multi-factor sensitivity analysis to understand the trade-off between different process parameters. 

The above cost estimation software shall provide a seamless link to the maintenance and direct operating cost modules also to be developed as part of the call as well as industrial commercially available multidisciplinary optimisation and FE software described below. 

In addition, the software for cost benefit analysis shall allow for incorporation of additional third-party modules such as probabilistic risk assessment (based on SHM diagnosis and prognosis) to evaluate the overall value of the SHM system for each structural part.

A Bayesian based Dynamic Data Driven Application System (DDDAS) will be developed by the topic manager and shall be integrated into the software platform “Figure 2”. The Bayesian based module developed within the SHERLOC project allows the characterization of uncertainty, and with the appropriate inference network they allow conditional probabilities to be determined in terms of what is known about the structure from the model and what is measured during the inspection. 

During the design of a sub-component, selection has to be done of the main characteristic to be optimised. However, if this is done in isolation without looking at future costs, there is a risk that small benefits gained from the optimised characteristics are achieved at high cost. Therefore, the SHERLOC-Cost-Optimisation software platform shall provide the benefit of automated simultaneous optimisation in tandem with the cost estimation.

This module shall link the developed cost model software to a multidisciplinary optimisation software such as Isight. The link with these programs shall allow the user to use a parametrised model of the part to automatically generate CAD models with varying geometry and part parameters such as layup, skin thickness and stringer height. The Finite Element program will provide the necessary analysis of these CAD models. The iterative optimisation process will be repeated for all design parameters and passed on to the cost module where the cost of the design is evaluated.