Optimization

Report
PhD Candidate: Zaoxu Zhu
Department: AWEP
Section: Flight Performance and Propulsion
Supervisor: G. La Rocca
Promoter: M.J.L. van Tooren
Start date: 01-12-2009
Funding: China Scholarship Council
Automatic 3D Routing for
Aircraft Wire Harness Design
Introduction
Methods
Nowadays, 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.
1.
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.
Optimization architecture of harness design
Progress
Start
MULTI MODEL GENERATOR(MMG)
initialization
Harness
Physical Model
Requirements
CM
CM
CM
CMs
Calculating product model
parameter values
& check of them on
1. compliance with
requirements
for
Clamping
Distance
Analysis
for
Bend
Radius
Checking
for
Geometry
Collision
Checking
for
Hazardous
Areas
Analysis
No
Yes
XML
1
IGES
Report writers
INITIATOR
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.
REPORT
FILES
...
OPTIMIZER
No
1
Analysis tools
HRATs
GCAT
HBRAT
CDAT
Check of analysis results on:
1. convergence
2. compliance with
requirements
Yes
No
2
Yes
Data
files
Aerospace Engineering
End
CDAT- Clamping Distance Analysis Tool
HBRAT- Harness Bend Radius Analysis Tool
GCAT – Geometry Collision Analysis Tool
HRATs- Hazardous aRea Analysis Tools
optimization
The Design and Engineering Engine (DEE) of physical
design of EWIS
A part of wire harness systems in A380
Objective
Wire harness design consists of two parts, Electrical Design
and Physical Design.
Electrical
design
Why
Physical
design
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.
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.
Original
Optimized
How
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.
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.
Nonlinear constrained optimization method
for 3D harness routing
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.
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
In collaboration with
Funded by

similar documents