Automatic 3D Routing for Aircraft Wire Harness

DesignIntroductionNowadays, wire harnesses of aircraft are becoming more and more complex. The complexity is associated with the increase in number of on-board electrical and electronic systems which connect with each other via Electrical Wiring Interconnection System (EWIS) consisting of a large amount of wire harnesses. An aircraft such as the A380 accommodates 530km of cables, 100,000 wires and 40,300 connectors. These harnesses have to be routed inside a narrow space, while accounting for the room reserved for cargo, passenger and equipment. Not only the wire harness is complex, but its design process is complex as well.The reasons of the complexity are listed below:1. wire harness design process involves many

disciplines such as electrical engineering, mechanical engineering.

2. the innovation of aircraft design raises the new problems of wire harness. For instance, Faraday cage does not exist anymore while the composites are used.

3. wire harness design process is subject to a large number of requirements, rules and regulations addressing the increasing number of constraints associated with electromagnetic interference, corrosion, abrasion, degradation, installability, maintainability and so on.

4. wire harness design is a very labor intensive process but still suffers the continuous design changes of other part of aircraft such as customization of airlines or modification 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

ObjectiveWire 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. OptimizationThe 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 ZhuDepartment: AWEPSection: Flight Performance and PropulsionSupervisor: G. La Rocca Promoter: M.J.L. van ToorenStart date: 01-12-2009Funding: China Scholarship Council

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Methods1. Knowledge Based Engineering:

Knowledge Based Engineering is a methodology which is able to automate certain steps of design process using Knowledge Based Engineering system (KBEs) to capture and store the involving process and product knowledge and to generate geometry model. The framework of the use of KBE to support 3D harness routing is called Design and Engineering Engine.

Start

End

Requirements

REPORT FILESXML IGES ...

INITIATOR

HBRAT

CDAT

Analysis tools

HRATs

GCAT

Calculating product model parameter values

& check of them on1. compliance with

requirements

OPTIMIZER

Check of analysis results on:1. convergence

2. compliance with requirements

MULTI MODEL GENERATOR(MMG)

Harness Physical Model

Report writers

No

YesDatafiles

2

No Yes

1

optimization

initialization

CMs

forHazardous

Areas Analysis

No

Yes

1

CM

for Clamping DistanceAnalysis

CM

for Bend

Radius Checking

CM

forGeometry Collision Checking

CDAT- Clamping Distance Analysis ToolHBRAT- Harness Bend Radius Analysis ToolGCAT – Geometry Collision Analysis ToolHRATs- Hazardous aRea Analysis Tools

Electrical design

Physical design

Why How

The Design and Engineering Engine (DEE) of physical design of EWIS

A. The INITIATOR is responsible for the preliminary design of wire harness while using the simplified geometry routing environment and design specifications.

B. The Multi Model Generator(MMG) is a KBE application, which is able to generate the geometry model for both analysis and design output. The geometry model generation is enabled by the High Level Primitives (HLPs) followed by Capability Modules (CMs), which prepare the data for the following analysis tools.The analyses of previous defined harness are implemented by Analysis Tools. And the analysis results are sent to OPTIMIZER to support the decision making of optimization. OPTIMIZER checks the convergence of design and satisfaction of constraints according to the analysis results and generates the new value of design variables.

AB

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 DevelopmentThe rest of this research will1. 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.