Automatic 3D Routing for

Aircraft Wire Harness Design

Introduction

Nowadays, wire harnesses of aircraft are becoming moreand more complex. The complexity is associated with theincrease in number of on-board electrical and electronicsystems which connect with each other via Electrical WiringInterconnection System (EWIS) consisting of a largeamount of wire harnesses. An aircraft such as the A380accommodates 530km of cables, 100,000 wires and 40,300connectors. These harnesses have to be routed inside anarrow space, while accounting for the room reserved forcargo, passenger and equipment.

Not only the wire harness is complex, but its designprocess is complex as well.

The reasons of the complexity are listed below:

1. wire harness design process involves many disciplinessuch as electrical engineering, mechanical engineering.

2. the innovation of aircraft design raises the newproblems of wire harness. For instance, Faraday cagedoes not exist anymore while the composites are used.

3. wire harness design process is subject to a largenumber of requirements, rules and regulationsaddressing the increasing number of constraintsassociated with electromagnetic interference, corrosion,abrasion, degradation, installability, maintainability andso on.

4. wire harness design is a very labor intensive processbut still suffers the continuous design changes of otherpart of aircraft such as customization of airlines ormodification of structure.

Progress

After years of development, part of the objective of this research has been reached.

The INITIATOR is able to generate a set of harness parameters to enable the following optimization.

The harness HLP of MMG is developed. Given the parameters generated either by INITIATOR or specified manually, it is capable of generating geometry models for following analysis or manufacture and installation.

Publications

-Zaoxu Zhu, Michel van Tooren, G. La Rocca, (2012) “A KBE Application for Automatic Aircraft Wire Harness Routing”, 53rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, DOI: 10.2514/6.2012-1843

-Zaoxu Zhu, Michel van Tooren, Stefan der Elst, (2011) “On the development of a heuristic routing application for the automatic wire harness design in the aircraft”, 52nd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, DOI: 10.2514/6.2011-2148

A part of wire harness systems in A380

Objective

Wire harness design consists of two parts, Electrical Design and Physical Design.

This research focuses on a part of physical design, namely: Harness 3D Routing which solves how to route the harness in aircraft.

The objective of this research includes:

1. developing a 3D harness routing system on one hand to store the knowledge of wire harness and its design process to support the automation of 3D harness routing, on the other hand to generate the harness 3D geometry model automatically for manufacture and installation.

2. developing 3D harness routing and optimization methods to achieve the automation of 3D harness routing and optimization on harness weight.

Optimization architecture of harness design

2. Optimization

The multi-level optimization method is applied to both the INITATOR and the rest part of DEE. The design and optimization of wire harness is decomposed into the design and optimization of each harness branch and the coordination of them.

In INITIATOR, the discrete optimization method is adopted to generate an set of feasible initial values for the following optimization.

Getting rid of the limitation of discretization, the optimization part of DEE is able to generate a less weight harness based on previous defined initial values.

PhD Candidate: Zaoxu Zhu

Department: AWEPSection: Flight Performance and PropulsionSupervisor: G. La Rocca

Promoter: M.J.L. van ToorenStart date: 01-12-2009Funding: China Scholarship Council

Aero

space

Engin

eering

Methods

1. Knowledge Based Engineering:

Knowledge Based Engineering is a methodology whichis able to automate certain steps of design processusing Knowledge Based Engineering system (KBEs) tocapture and store the involving process and productknowledge and to generate geometry model. Theframework of the use of KBE to support 3D harnessrouting is called Design and Engineering Engine.

Electrical

design

Physical

design

Why How

The Design and Engineering Engine (DEE) of physical

design of EWIS

A. The INITIATOR is responsible for the preliminarydesign of wire harness while using the simplifiedgeometry routing environment and design specifications.

B. The Multi Model Generator(MMG) is a KBEapplication, which is able to generate the geometrymodel for both analysis and design output. Thegeometry model generation is enabled by the HighLevel Primitives (HLPs) followed by Capability Modules(CMs), which prepare the data for the following analysistools.

The analyses of previous defined harness areimplemented by Analysis Tools. And the analysisresults are sent to OPTIMIZER to support the decisionmaking of optimization. OPTIMIZER checks theconvergence of design and satisfaction of constraintsaccording to the analysis results and generates the newvalue of design variables.

A wire harness model generated by MMG

The optimization part of DEE is partly validated although it is not yet developed completely. The optimizer is able to generate a better solution based on the given initial values.

Funded byIn collaboration with

Nonlinear constrained optimization method

for 3D harness routing

Original

Optimized

Future Development

The rest of this research will

1. complete the development of Design and Engineering Engine of the physical design of EWIS.

2. validate the 3D routing system using the realistic geometry models.