BAE Systems Research Articles

3.2.3 Modelling Uncertainty in Integrated Models

AbstractOne of the main aims of modelling is to ensure that customer requirements (stated in terms of property value constraints) will be met with a suitably high level of confidence. This paper introduces work ongoing jointly within BAE SYSTEMS and the University of Newcastle‐upon‐Tyne in the UK which, in part, introduces processes and techniques to enable this aim to be realised. Part of this work involves the creation of a modelling framework to represent property flow within an integrated modelling hierarchy to aid model and property traceability and to determine and propagate both subjective and quantitative model dependability (confidence we have in the output from models).The aim of the joint research is, in part, to determine the confidence we have in the values of the top level properties, to determine the critical lower level properties and to ease trade‐off studies.

Metal spray tooling for composite forming

Thermal spraying methods have been mooted as a method of manufacturing tooling for many years and yet they have not made a significant in-road into this market. Generally, recent metal spraying research has focussed on the manufacture of small, high-pressure tools (for example, for automotive injection moulding tools). However, the metal spray process really lends itself to the manufacture of large tooling where it can compete more effectively against alternatives such as machining. The 3-year, £ 750k, IMI Spray Mould Programme, funded jointly by EPSRC (IMI) and the industrial partners: Airbus, BAE SYSTEMS, Bombardier Aerospace Shorts, A.T. Poeton, Rover Group, and Sulzer Metco, commenced in June 1997. The aim of this research is to develop a method of manufacturing tooling for composite aerospace components, particularly large primary structures over 15 m in length. This paper will present the results of this research programme, including technical data comparing both the technical and economic advantages of this novel approach to tool construction.

Model-Based Autopilot Design for a Remotely Operated Submersible

This paper demonstrates the benefits of using a model based design approach for the rapid prototyping of new control systems. BAE SYSTEMS, with assistance from The MathWorks, have carried out the work as part ofa pilot study into the development of an autopilot for a remotely operated submersible. The design stages are similar to the development of any flight control system, namely, the development of models used by systems engineers in the design and analysis of the control algorithms, followed by the development of real-time simulation models to assess handling qualities with a pilot in the loop, and finally the generation ofreal-time software for hardware in the loop testing and initial trials.

Electric propulsion for future carriers

The two new aircraft carriers due to be built by BAE Systems and Thales will have electrical propulsion with all power generated by gas turbines. The new aircraft carriers will thus join a new generation of electrically propelled Royal Navy warships, a generation which includes the Daring Class Type 45 anti-air warfare destroyers, which are the first warships in the world to incorporate fully integrated electric propulsion and power. It is thought likely that power will be generated by four of the new Roll-Royce MT-30 marine gas turbines. The decision to adopt electric propulsion for the future carriers accords with a general Royal Navy marine engineering policy whose aim is to build all-gas turbine ships with electrical propulsion, auxiliary and weapon systems.

Natural Resources and Cultural Heritage of the Libyan Desert: report on a conference held in Libya 14-21 December 2002

The Society for Libyan Studies (SLS), in concert with the Libyan Environment Agency (EGA), the Biruni Remote Sensing Agency, the British Council and the British Embassy, Tripoli, organised a major international and interdisciplinary conference on the Sahara desert, held in Tripoli and southern Libya in December 2002. This marked the culmination of two years' planning and preparation after the idea was initiated by David Mattingly, whilst Chair of the SLS. On the Libyan side, the organising committee was chaired by Dr Ehtuish F. Ehtuish (Secretary of Natural Resources, Environment and Urban Planning), with the main organisational work being carried out by Dr Khaled Gadgood and Dr Ahmed Tawangi of the EGA, along with Dr Yahya al-Fasatwi of the Biruni Remote Sensing Centre. The conference received strong backing from successive British Ambassadors, Richard Dalton and Anthony Layden, and the role of Tony Jones, British Council Director in Tripoli was crucial in finalising all the practical arrangements. Anthony and Josephine Layden kindly hosted a reception to welcome conference delegates on 14th December. The British Council and British Embassy also provided financial support towards travel costs of external speakers and the hire of facilities in Tripoli. Additional sponsorship for the conference was received from Shell, BAE Systems, the Arab-British Chamber of Commerce. British Council staff worked tirelessly during the conference to ensure close liaison with our Libyan hosts. The southern tour (see below) received considerable practical support from the local government agencies (shaʿabiyāt) in Fazzan. The general organisation of the conference was superb, for which our Libyan hosts were much congratulated.

Comparison of HgCdTe and quantum-well infrared photodetector dual-band focal plane arrays

We report on results of laboratory and field tests of dual-band focal plane arrays (FPAs) in the medium-wave infrared (MWIR) and long-wave infrared (LWIR), produced under the Army Research Laboratory's Multidomain Smart Sensor Federated Laboratory program. The FPAs were made by DRS Infrared Technologies using the HgCdTe material system, and by BAE Systems using quantum-well infrared photodetector (QWIP) technology. The HgCdTe array used the DRS HDVIPTM process to bond two single-color detector structures to a 640×480-pixel single-color readout integrated circuit (ROIC) to produce a dual-band 320×240 pixel array. The MWIR and LWIR pixels are co-located and have a large fill factor. The images from each band may be read out either sequentially (alternating frames) or simultaneously. The alternating-frame approach must be used to produce optimal imagery in both bands under normal background conditions. The QWIP FPA was produced using III-V materials grown by molecular-beam epitaxy (MBE). The LWIR section consisted of GaAs quantum wells and AlGaAs barriers, and the MWIR section used InGaAs quantum wells with AlGaAs barriers. The detector arrays were processed with three ohmic contacts for each pixel, allowing for independent bias control over both the MWIR and LWIR sections. The arrays were indium bump-bonded to an ROIC (specifically designed for two-color operation), which puts out the imagery from both bands simultaneously. The ROIC has variable gain and windowing capabilities. Both FPAs were tested under similar ambient conditions with similar optical components. The FPAs were subjected to a standard series of laboratory performance tests. The advantages and disadvantages of the two material systems for producing medium-format dual-band FPAs are discussed.

Context Switching in a Run-Time Reconfigurable System

A distinguishing feature of reconfigurable computing over rapid prototyping is its ability to configure the computational fabric on-line while an application is running. Conventional reconfigurable computing platforms utilize commodity FPGAs, which typically have relatively long configuration times. Shrinking the configuration time down to the nanosecond region opens possibilities for rapid context switching and virtualizing the computational resources. An experimental context-switching FPGA, called the CSRC, has been created by BAE Systems, and gives researchers the opportunity to explore context-switching applications. This paper presents results obtained from constructing both control-driven and data-driven context switching applications on the CSRC device, along with unique properties of the run-time and compile-time environment.

Dimensional variations during Airbus wing assembly

The introduction of automation for the assembly of aircraft wing box structures will require individual components to conform closely to the CAD design specification with regard to shape geometry and dimensional tolerances. Often, due to a variety of previous manufacturing processes, the 3D shape of these large components lose the accuracy of their designed dimensional specifications. Under these circumstances part‐to‐part assembly becomes tedious and it would be impossible to rely on robots to achieve precise assembly in an automated system. For this reason, variations need to be accurately quantified in order to provide a reliable prediction model in aid of any future automated assembly. This paper describes the measurement method used to record the possible variations occurring during the assembly process. The measurements were made using a laser tracker where the results are expected to offer some explanations as to the causes of the variation. The suitability of a laser tracker in a large assembly jig environment is then assessed. This study is based on the work that was carried out at BAE Systems UK, where the Airbus commercial aircraft wings are manufactured.

4.4.3 It's the people that matter – applying a Systems Engineering approach to process improvement

AbstractThis paper describes approaches taken within the UK Warship Support Agency (WSA) and BAE SYSTEMS to implement improved Systems Engineering processes throughout complex supply chains. The supply chains needed to develop and support complex products, such as large aircraft or warships, require large teams to collaborate across organisational and cultural boundaries.To be successful the extended enterprise needs business processes which are honed to drive down life cycle costs and which manage the key emergent capabilities such as safety, availability, flexibility, and reliability. Such business processes are heavily dependant upon the people in the system and those people represent a complex web of interdependant factors. Improving these processes, which are almost exclusively goal and knowledge based, therefore requires significant understanding of how to integrate diverse teams and cultures.This paper describes the techniques used within the WSA's Enterprise Integration and Shared Data Environment Team and BAE SYSTEMS Advanced Technology Centre in understanding and improving complex goal and knowledge based processes. It describes how the teams analyse improvement requirements, and how they implement change in such a difficult, but critical, area.

1.2.3 A Structured Approach to Developing a Systems Capability

AbstractIn November 1999, British Aerospace and Marconi Electronic Systems merged to become BAE SYSTEMS, one of the 3 largest Systems, Aerospace and Defence companies in the world. In order to maintain and improve the company's capability, Engineering Developing You (EDY), has been created. EDY forms part of an integrated framework for personal and professional development – but with over 20,000 engineers just in the UK, and almost the same number again in overseas divisions and joint ventures ‐ the task itself is far more complex than may at first appear.For an (ex‐)Systems Engineer now working in the Virtual University, given the task of designing and developing this framework, using a structured Systems Engineering approach seemed to be a sensible approach. So how easy was it to apply a ‘soft system’ approach and how successful has it been ??

Five year agreement with BAE Systems

Five year agreement with BAE Systems

BAE Systems to form engineering colleges

BAE Systems to form engineering colleges

Annual BAE systems lecture can partnering deliver?

Annual BAE systems lecture can partnering deliver?

REDUCING STRUCTURAL COUPLING ON A FLEXIBLE BEAM USING KALMAN FILTERS

Structural coupling is the disturbance to the aircraft's inertial sensors caused by the flexibility in the airframe, and is particularly problematic for modern combat aircraft. The current solution uses a series of notch filters to remove the structural frequencies, but these introduce significant phase delays into the control loop. This paper presents some experimental and theoretical results from a flexible beam, and the use of Kalman filters to reduce the effects of structural coupling. This work is part of an ongoing project in conjunction with BAE Systems.

Quality management system design: A visionary approach

The quality management systems of many large companies have evolved by default rather than by design. Retrieving this situation to produce an effective and efficient quality management system (QMS) is never easy—there always seem to be too many other priorities. This paper addresses this difficult issue by discussing the process devised by the author that is being used to transform the QMS used by BAE SYSTEMS, Aircraft Programmes. The process uses the derivation of an agreed QMS vision as the basis for establishing ‘what's in it for me’ statements that are used to gain senior management desire/commitment for/to the proposed change. Selecting the appropriate time to propose such a change can have a significant enabling effect on the ability to gain agreement. With this mandate, cross-functional QMS users (sufferers) and quality professionals jointly agree change objectives and produce a detailed design for review and agreement amongst key stakeholders. Prime QMS users are involved throughout to maintain ownership and to provide confirmation that the changes will indeed realize the estimated benefits. Critically, throughout the development communication and training programmes are concurrently provided so that when the new QMS is launched, information owners and users can implement the change with familiarity and confidence. Post implementation activities provide initial intensive support to overcome any learning curve difficulties, measurement to confirm successful implementation and the establishment of an easy mechanism for users to propose further improvements.

A career in the defence industry

I had enjoyed science ever since I was at school–but when it came to leaving university, I was more keen to work in industry than stay on in academia. What I didn't envisage, however, was crawling about a ship in a boiler suit, presenting my work to the Ministry of Defence, or managing contributions to multi-million pound contracts. Yet these are just some of the experiences I've had as a physicist working at BAE SYSTEMS.

£6 million contract to support BAe Systems

£6 million contract to support BAe Systems

A new method for evaluating the residual compression strength of composites after impact

In the aerospace industry, compression panels are usually designed not to buckle at ultimate load. To obtain design allowables, test boxes have been used which are more representative to the real structure but are complex and expensive. Therefore, a simpler and cheaper method has to be devised to mimic the real structure and gives more realistic results for compression after impact (CAI). This paper analyses the results of experimental studies using the new BAE Systems CAI rig. Three different thicknesses, 4, 6 and 8 mm composites plate specimens have been impacted at different energy levels followed by CAI tests. The support conditions were identical for the impact and CAI tests but differed for the three plate thicknesses. The effects of impact damage on the initial buckling load and compression strength was seen at the threshold energy for the 4 mm plate and two times the threshold energy for the 6 and 8 mm plates. The experimental results for the unimpacted plates were compared with finite element results. The plates with its supports conditions were modeled using the FE77 code and a good correlation was apparent between the experimental and finite element values of the initial buckling load, within 9%.

7.1.2 Similarity Workshops as a Project Initiation Tool

AbstractThis paper discusses the theory and initial results of the application of the ideas regarding ‘similarity’ introduced by Verma (Verma 1998) as a means of improving ‘left shift’ in the Systems Engineering lifecycle at BAE SYSTEMS. In particular, it concentrates upon the practical application of these ideas in a real world environment.

Proposal to TPS delivery in 4 months?

Decreasing the often lengthy Test Program Set (TPS) development time is a high priority for both DoD and commercial industry. A protracted test development time for a commercial product can make or break its success. It can impact time-to-market goals for a product, which in turn, can result in a loss of market share. Though the DoD world has different objectives, they, too, are concerned with long test development times which can increase costs and jeopardize a weapon system's mission readiness. The case study for this paper is a test system developed by BAE Systems in less than four months to meet a commercial customer's stringent schedule requirements. The factors that contributed to the success of this project are examined, as is their relevance to the DoD world. The desire is to apply relevant lessons learned from the commercial industry to DoD programs, yielding a decrease in TPS development time.