Mechatronics 20 (2010) 827–841

Contents lists available at ScienceDirect

Mechatronics

journal homepage: www.elsevier .com/ locate/mechatronics

Mechatronics – More questions than answers

David BradleySchool of Computing & Engineering Systems, University of Abertay Dundee, Bell Street, Dundee DD1 1HG, UK

0957-4158/$ - see front matter � 2010 Elsevier Ltd. Adoi:10.1016/j.mechatronics.2010.07.011

E-mail address: d.bradley@abertay.ac.uk

a b s t r a c t

Since the introduction of mechatronics as an integrated and integrating approach to the design, develop-ment and operation of complex systems, there have been significant developments in technology, and inparticular in processing power, which have changed the nature of a wide range of products and systemsfrom domestic appliances and consumer goods to manufacturing systems and vehicles. In addition, thedevelopment and implementation of strategies such as those associated with concurrent engineeringand the introduction of intelligent tools to support the design of complex products and systems has alsochanged the way in which such systems are conceived, implemented and manufactured.

The aim of the paper is not however to attempt to address or answer specific questions as to the natureof mechatronics and its current and future standing as an approach to engineering design and develop-ment, but to initiate, provoke and stimulate debate and discussion on a range of mechatronics relatedissues, without necessarily attempting to provide answers or suggest new methods or approaches, relat-ing to the future potential of and directions for mechatronics. In this respect therefore, while containingan element of review, the paper is intended as a discussion document structured around the author’s per-sonal experience and perspective of mechatronics issues.

Inherent to this questioning of the ways in which mechatronics may develop are the various attemptsthat have taken place over the years to provide a definition of mechatronics, either in the form of text orlogo and whether these efforts have of themselves been a source of confusion as to both content anddirection within mechatronics? In which case, might it be preferable for mechatronics practitioners tooperate within their own particular context than to attempt to conform to a specific and overarching def-inition?

Finally, it must also be made clear that in writing this paper that complete agreement with the readeras to the particular questions raised and comments made is neither sought nor intended.

� 2010 Elsevier Ltd. All rights reserved.

1. Introduction

Over many years of involvement with mechatronics it has be-come increasingly challenging at a personal level to reconcile thevarious different and differing arguments as to what it is that de-fines, constitutes and differentiates mechatronics with respect torelated engineering disciplines such as systems engineering, con-trol engineering, design engineering and manufacturing systemsas well as identifying its continuing role in education [1]. Theaim in writing this paper is not however to attempt to answerthe general questions of ‘what is mechatronics?’ or ‘how mightmechatronics be defined?’, but to raise these and other questions,without necessarily providing answers, with the intent of provok-ing debate and discussion as to the future potential of and direc-tions for mechatronics as an engineering discipline. For instance,is there, or indeed could there be, a single overarching structurefor mechatronics, or are there several interrelated and interlinkedstructures, each emphasising a specific aspect of the whole?

ll rights reserved.

Thus while the paper incorporates a review element in respectof certain aspects of mechatronics, it is not aimed at providing adetailed analysis of a specific aspect of mechatronics or of propos-ing new and novel structures for the discipline but at posing ques-tions relating to its future role and development. It shouldtherefore be considered as a discussion paper presenting a partic-ular, and personal, viewpoint, in this case that of the author.

In developing the discussion it is necessary to consider the waysin which mechatronics is perceived. Various attempts have takenplace over the years since its introduction to provide a ‘concrete’definition of mechatronics, either in the form of text or logo. Asan illustration of this activity, one web site [2] lists over 20 defini-tions of mechatronics, each of which places a slightly differentemphasis on the central theme of the integration of the core disci-plines of electronics, mechanical engineering and informationtechnology1. Similarly, a search for mechatronics logos suggests thatmany academic and other institutions engaged in aspects of mecha-tronics have attempted, at various degrees and levels of complexity,

1 Or Computing, Information Systems and other variants.

Table 2Some milestones in mechatronics.

1940 Isaac Asimov published the first of his robot stories and develops the‘Three Laws of Robotics’

1948 Transistor is developed at Bell Laboratories by John Bardeen, Walter H.Brattain and William B. Shockley

1952 A prototype Numerically Controlled machine is demonstrated atMassachusetts Institute of Technology

1958 Texas introduces the first commercial integrated circuit1959 Planet Corporation introduces the first commercial robot based on

limit switches and camsRichard Feynman delivers the lecture There’s Plenty of Room at theBottom at Caltech [2]

1961 A Unimate robot is installed by Ford to service a die-casting machineThe part programming language APT (Automatically ProgrammedTooling) is released

1963 The American Machine Company introduces the Versatran robot1965 Gordon Moore proposes that the size of integrated circuits will double

approximately every 2 yearsDigital Equipment Corporation introduces the PDP-8 computer

1968 Burroughs produces the first computers to use integrated circuits1969 The term mechatronics is proposed by Tetsuro Mori to describe the

integration of electronics with mechanical engineering1970 Digital Equipment Corporation introduces the PDP-11 computer1972 8-bit microprocessors introduced1974 ASEA introduce the all electric drive IRb6 robot

828 D. Bradley / Mechatronics 20 (2010) 827–841

to produce something which reflects both the nature of the institu-tion and its mechatronics context.

Could it however be argued that an such attempt to provide anyform of expression of mechatronics, whether textually or graphi-cally, may of itself be a source of confusion and that it may there-fore be better for mechatronics practitioners to operate withintheir own particular context than to attempt to conform to a spe-cific and overarching definition?

In order to place the subsequent discussion into context, the pa-per begins by providing an overview of the introduction of mech-atronics, its initial concepts and the ways in which it hasdeveloped. By its very nature and breadth, Table 1 provides anindication of the topics that have been and are associated withmechatronics, any of which could have been chosen to illustratethe arguments within the paper, this means that a choice hashad to be made, in this case that of engineering design. It must alsobe acknowledged that in writing this paper it will be inevitablethat issues which individual readers consider important will havebeen omitted and apparently ignored. No apology is made for thisother than those of limitations of space and the background, viewsand opinions of the author, and complete agreement with the read-er is neither sought nor intended.

The T3 robot Tomorrow Tool, better known as the T3 robot, isintroduced by Cincinnati Milicron

1978 The PUMA (Programmable Universal Machine for Assembly) isintroduced by Unimation16-bit microprocessors introduced

1979 The SCARA (Selective Compliance Arm for Robotic Assembly) arm isdeveloped at Yamanshi University in Japan

1980 Intel introduces the first 32-bit microprocessor1981 IBM introduces a personal computer with an industry standard disc

operating system (DOS)1982 IBM introduces the RS-1 assembly robot1984 Sumitomo demonstrates an organ playing robot developed at Waseda

University in Japan1988 Institute for Defense Analysis Report R-338 on concurrent engineering

is published1990 The World Wide Web is set up by Tim Berners-Lee at the European

Particle Physics Laboratory in Switzerland1993 Intel introduce the Pentium processor1997 Pathfinder mission lands the Sojourner vehicle on Mars1998 Honda introduces the P3 humanoid robot1999 Sony introduces the AIBO robot dog2000 AMD released the Athlon 1 GHz

Honda introduces the ASIMO humanoid robot2001 First autonomous flight over the Pacific by the Global Hawk unmanned

aerial vehicle2004 Rovers Spirit and Opportunity land on Mars2005 DARPA Grand Challenge, five teams completed the off-road course

with Stanford University’s Stanley the winner2006 Intel introduces the Core 2 processor

Sony releases the Playstation 3Nintendo releases The Wii

2007 TOMY introduces the i-sobot humanoid robotApple launches the iPhone

2. The growth of mechatronics

The first commercial and industrial use of the term ‘mechatron-ics’ is generally credited to Tetsuro Mori in 1969 [3–5], though itmay well have been used informally several years earlier by Profes-sor Takashi Kenjo [6]. Since its introduction, it has generally beenargued that mechatronics represents a significant, and initially dif-ferent, approach to the design, development and implementationof a wide range of inherently complex products and systems. Whilethat may have been the case when the concept was originally pro-posed, can this view be sustained 40 years later [7]?

Consider the very much abbreviated timeline of Table 2 as towhat might be considered mechatronic oriented developments.This list must however also be placed in the context of earlierdevelopments and not taken as implying that systems and techni-cal integration began with mechatronics. Consideration of the ear-lier years of the 20th century provides many examples of suchintegration ranging from the naval gunnery control systems basedaround integrated optics and mechanical analogue computers [8]to aircraft flight control and inertial navigation systems [9]. Inmanufacturing, the introduction and development of mass produc-tion systems integrated with developments in machine tool tech-nology also supported the underlying concepts of systemsintegration generally felt to be integral to mechatronics. In addi-tion, mechatronics has developed to encompass issues such as bio-mechatronics, focused on issues such as the analysis of humanmotion, interfacing with the nervous system and ways in which

Table 1Some mechatronics applications areas.

Automation and robotics Machine visionAutomotive engineering Mechatronics systemsComputer aided and integrated

manufacturing systemsMedical systems

Computer Numerically Controlled machines PackagingConsumer products Sensing and control systemsDiagnostic, reliability, and control system

techniquesServo-mechanics

Engineering design Structural dynamic systemsEngineering and manufacturing systems Systems engineeringExpert systems Transportation and vehicular

systemsIndustrial goods

to use muscle tissue as actuators [10–12] and micromechatronics,generally associated with MEMS2 technologies [13,14].

What may however be considered to be of particular signifi-cance to the development of mechatronics from the 1960s on isthat at about the time that the concept was first being mooted,computers such as the PDP-8 and PDP-11 were beginning to im-pact upon the industrial and process control markets. Though ini-tially limited in power and scope, at least in current terms, suchcomputers nevertheless provided a whole series of lessons thathave stood future systems designers and integrators in good stead.Consider for instance the development of avionics where in the1960s aircraft designers and manufacturers began to conceive of

2 Micro Electro-Mechanical Systems.

D. Bradley / Mechatronics 20 (2010) 827–841 829

the translation of the complex analogue flight control and enginemanagement systems into their digital equivalents, initially inthe form of electronic logic and then by means of microprocessorbased systems and their subsequent developments, and werethinking in those terms even before the necessary devices became

Table 3Apollo Primary Navigation and Guidance System (PNGS) computer specifications.

Developed by MIT instrumentation laboratoryManufacturer RaytheonProcessor Discrete IC RTL basedFrequency 2.048 MHzMemory 16-bit words, 2048 words RAM (magnetic core memory),

36,864 words ROM (core rope memorya)Ports DSKY, IMU, Hand Controller, Rendezvous Radar (CM),

Landing Radar (LM), Telemetry Receiver, Engine Command,Reaction Control System

Power 70 WWeight 70.1 lb (31.8 kg)Dimensions 24 � 12.5 � 6.5 in. (61 � 32 � 17 cm)

a The core rope memory consisted of a series he ferrite cores operating as trans-formers. The signal from a word line wire passing through a core was coupled to thebit line wire and interpreted as a binary ‘‘one” while a word line wire that bypassedthe core was not coupled to the bit line wire and was read as a ‘‘zero”. Up to 64wires could be passed through a single core. Software written by NASA program-mers was ‘woven’ into the cores to create the ‘rope’. [86].

Computer

EngineCommands

AttitudeControls

DataDisplayTelemetry

ManualControlSignals

NavigationStar Tracking

Inertial Platform

RadarRange

DirectionVelocity

Display &DSKY

Keyboard

Fig. 1. Apollo Primary Navigation and Guidance System (PNGS) computerfunctions.

RequirementsDefinition

Quality

Design fortestability

Conceptualdesign

Design forManufacture

Marketing

Industrialdesign

Interfacedesign

S

Em

Manp

Fig. 2. Concurrent engi

available [15]. It is also perhaps salutary in this context to recog-nise that the Apollo Primary Navigation and Guidance System(PNGS) computer, essentially a digital fly-by-wire unit, developedfor the Moon landing programme from 1969 to 1972 had the spec-ifications and functions as set out in Table 3 and Fig. 1 [16].

However, at the start of the 21st century, computing technolo-gies have matured and developed to the point where processingpower is available at near zero cost to the system developer. Sys-tem costs are then to a very large degree those associated withachieving integration and developing the software required tomeet user perceptions in what continues to be a rapidly developingmarket place.

While technology was evolving, so to was the concept of engi-neering design changing from the static and linear strictures asso-ciated with the established concepts of sequential development,and all the problems associated with this, to the introduction ofthe concepts of concurrent engineering with its implied parallelismas illustrated by Fig. 2 [17,18].

Thus whilst the original concept of mechatronics as concen-trated on the integration of electronics with mechanical engineer-ing and software, is it now the case that the emphasis needs to shiftto one which encompasses a more holistic view of system designand development?

This shift, as suggested in part by Fig. 3, would effectively placemechatronics within a network of engineering functions and issuesranging from aesthetics to marketing. In reviewing this network itis however also important to recognise and understand that mech-atronics, and indeed engineering design in general, is not solelyconcerned with or about technology but relies on people, and inparticular on the interactions between individuals, to make itwork.

Is it therefore the case that mechatronics can no longer, asmight have originally have been the case, be considered purelyas being associated with the integration of specific technologiesbut as a systems oriented approach to the design, developmentand implementation of complex systems which takes as its founda-tion the transfer of functionality from the physical domain to theinformation domain? This view is reflected in the comment byMillbank that [19]:

‘By definition then, mechatronics is not a subject, science or tech-nology per se – it is instead to be regarded as a philosophy – a fun-damental way of looking at and doing things, and by its very naturerequires a unified approach to its delivery.’

ervice &Support

bodiment

ufacturingrocesses

Manufacture Product

neering work flow.

Politics

SociologyPsychology

Economics

EngineeringDesign

IndustrialDesign

Artistic Design

Art

EngineeringTechnology ProductionEngineering

ScienceScience

Fig. 3. Mechatronics and engineering design issues.

100%INNOVATORS EARLY

ADOPTERS

Time

Mar

ket p

enet

ratio

n

MAIN MARKET

INNOVATORS EARLYADOPTERS

PRAGMATISTS SCEPTICS

Time

Rel

ativ

e pe

rcen

tage

of

cust

omer

s

MAIN MARKET

100%

(a) Adoption (b) Market penetration

PRAGMATISTS SCEPTICS

Fig. 4. Profiles of technology adoption and market penetration.

3 Sun Small Programmable Object Technology.

830 D. Bradley / Mechatronics 20 (2010) 827–841

The strength of such an approach may then be that it supportsthe understanding of the nature of the embedded complexity byensuring that the different engineering, and other, disciplines areconsidered together from the start of the design process.

That such a parallelism is important may be seen from the factthat products typically generate the most revenue early in their lifecycle, particularly if the product offers new features not present inits competitor’s products. As the product matures and competitorsenter the market, profit erosion will begin to occur as the compe-tition for available customers increases. It is therefore importantthat products are designed and produced on time and that produc-tion rates are rapidly ramped up to mature levels. Any delays in therelease of the product to the market will translate into lost salesthat will not be recovered over the life of the product.

As indicated by Fig. 4, a key element of the market profile is theneed to convince the pragmatists that the system is of value tothem once the innovators and early adopters have opened up themarket [20,21]. The introduction of a mechatronic approach totechnology integration allied to a concurrent engineering develop-ment strategy has historically resulted in products which areinherently more capable, and hence more attractive to the prag-matic users, than their predecessors at reducing real costs.

In recent years, products and systems of all types from domesticappliances to vehicles have become increasingly complex. Thiscomplexity may often be defined in turn by the combination of lo-cal and distributed processing power with mechanical design andis driven by the increased availability of processing power basednot only around microprocessors but of devices such as ApplicationSpecific Integrated Circuits (ASICS) and Field Programmable GateArrays (FPGAs) allied to enhanced communications strategies andprotocols. Thus at one level, a system such as the Wii games con-sole utilises three-axis accelerometers to record motion and to

translate that motion into an on screen response by means of aBluetooth communications link. At another level a modern car willintegrate multiple systems ranging from engine management todriver and passenger comfort controls and potentially even auton-omous navigation [22,23].

These developments are supported by the increasing availabil-ity of ‘smart components’ such as the SunSPOT3 system from SunMicrosystems [24], which in turn facilitate the construction of largersystems utilising the embedded processing power of their distrib-uted elements. The increasing availability of system elements suchas SunSPOTs and RFID tags is resulting in increasingly complex sys-tems in which the ability to analyse and interpret the data then be-comes the major source of added value. Thus while historicallymechatronics has been associated with system products such asvehicles and manufacturing technologies such as robots, these samemechatronic concepts are now appearing in applications such ashealthcare.

So, does mechatronics remain something that could, or indeedshould, continue to be considered as separate and distinct fromother approaches to engineering and engineering design, or has itsome 40 or more years after the term was proposed, becomeembedded within mainstream engineering? Or is it the case thatboth contentions are to some degree correct?

Consider first the validity or otherwise of treating mechatronicsas a separate and distinct approach to engineering design. Giventhe increasing complexity of systems, and of the integration oftechnologies that this implies, there is a need to ensure and man-age the communication between the domain specialists whilstensuring that there is awareness of the need to transfer functional-

D. Bradley / Mechatronics 20 (2010) 827–841 831

ity and complexity between domains [25]. By its nature, mecha-tronics has implied such an integration across disciplines, andhence an awareness of mechatronic approaches and outcomes bya design team is likely to be supportive of the appropriate identifi-cation of the range and variety of solutions associated with these. Asimilar case can also be made in relation to the teaching of mech-atronics within undergraduate and postgraduate engineering pro-grammes as a means of generating a breadth of awareness notnecessarily associated with more conventional, and single disci-pline, engineering courses and programmes [26–29].

However, as the majority of engineering systems are now inher-ently integrated and interdisciplinary in nature, an effective casecould perhaps also be made that the engineering design processhas itself adapted to accommodate the need to manage technicaland other integration at all levels within that process. This is illus-trated here by comparing the design model proposed by French[30] and shown in Fig. 5 with the V-Model [31] of Fig. 6, the laterinitially being for software development but increasingly used todescribe system development.

As can be seen from Fig. 5, while French’s model incorporateselements of feedback, it follows an essentially linear representa-tion of the design process with minimum embedded parallelism.In contrast, the V-Model attempts to combine the sequential ele-ments with appropriate evaluation, for instance by stressing the

Need

Analysis ofProblem

Statementof Problem

ConceptualDesign

SelectedSchemes

Embodimentof Schemes

Detailing

WorkingDrawings

Feed

back

Fig. 5. French’s design model.

need to design the test processes along with the system rather thanseparately as had often historically been the case.

Other examples of the holistic approach to design that may nowbe considered as common are the use of a ‘Third Age Suit’ by Fordengineers [32,33] to allow younger members of the design teamto evaluate the physical layout of a vehicle from the perspectiveof someone with reduced joint flexibility, vision and dexterityand the establishment by Volvo of an all female design team to re-view concept vehicles [34]. Whilst neither of these examples isexplicitly associated with design integration or mechatronics, theyare illustrative of the parallelism now found in most design teams.In this context therefore, should mechatronics now be consideredas being an element of the mainstream design process rather thana separate and independent design strategy?

Following on from the above, should it be considered that theissues previously associated with the design of mechatronic sys-tems are now essentially those associated with the design of alltypes and forms of complex, integrated systems?

3. Successes and failures

The danger in considering mechatronics from the standpoint ofthe various developments presented in the previous section is thatit may come to be perceived as a continuous and continuing suc-cess story. That is indeed far from being the case, and any reviewof literature will reveal the various flaws in any such argument.Whilst it is not the aim of this paper to go into the detailed reasonsas to why failures occur, it is possible to explore, albeit briefly, thereasons behind some of these failures within a mechatronic, andindeed a more general systems context.

3.1. A misunderstanding of the relationships between systemtechnologies, and particularly software

Engineering disciplines such as mechanical design and controlengineering have often followed an essentially separate pathwhilst acknowledging a commonality of approach in certain areas.This has led on occasion to control systems being deployed at a rel-atively late stage in the development process to accommodatedeficiencies in the mechanical design of a system, rather than theirhaving been considered as a part of that system from the firstinstantiation.

This problem was perhaps exaggerated or exacerbated whenthe view developed in some quarters that ‘it is all software now’,and that as changes to the software were considered as relativelyeasy, changing the system was in turn easy. This then led to furthercomplications as the demands on software by other parts of thesystem were continually changing as ‘it was simple to make thechange there’! In fact, both these approaches led to delays anderrors.

As an illustration of this type of failure, consider the case of aflight F22 Raptors transferring from Hawaii to Okinawa in 1997which when they crossed the International Date Line lost all navi-gation aids. The problem was traced to a coding error which re-sulted in an infinite loop as a consequence of the unexpecteddate change. In the words of Donald Shepperd, a former head ofthe US Air National Guard, ‘‘Reliance on electronics has changedthe flight-test process. It used to be tails falling off, now it’s typos thatground a fighter.” [35,36].

3.2. Problem complexity and communications

As systems become increasingly complex, it is difficult, and of-ten indeed impossible, for any single individual to manage all thelevels of detail required. This leads to a necessary partitioning of

RequirementsAnalysis

RequirementsDocuments

Specificatiion

Specification

High-LevelDesign

DesignSpecification

DetailedDesign

ModuleDesign

Construction/Coding

Modules

Service

CertifiedSystem

Certification

VerifiedSystem

System Test

IntegratedSystem

SystemIntegration

TestedModules

Module TestDevelopmentPhase

Output fromPhase

Test Planning

Test Planning

Test Planning

TestPlanning

Fig. 6. The V-model.

832 D. Bradley / Mechatronics 20 (2010) 827–841

function to levels at which an individual can operate. This in turnimplies that there is an understanding at the level of the ‘domainexperts’ both of their specific task and of the nature of that taskwithin the wider context of the overall system. Failure to achievethis understanding can then have a significant impact on the out-comes of the design process.

Thus, the Mars Climate Orbiter (MCO) was lost in 1999 when afailure in communications between the group responsible for nav-igation, who customarily used Newton-seconds to express thrust,and that responsible for the propulsion system, who in contrastused pound-seconds to express thrust, resulted in the MCO being100 km too close to Mars when it attempted to enter orbit [37].

A further issue associated with system complexity is that offault detection and diagnosis. While it would normally be the casethat individual sub-systems and sub-assemblies are tested in theirown right, this is often achieved through the use of synthetic datato represent the remainder of the system. A ‘hardware-in-the-loop’simulation being an example of this. However, when the sub-assemblies are connected to form the complete system, their indi-vidual interactions can result in faults and abnormal behaviourswhich are extremely difficult to detect.

3.3. An overemphasis on core disciplines

The name mechatronics by implication and usage has, as re-ferred to earlier, become associated with the three core disciplinesof electronics, mechanical engineering and information technologyor computing. This can result in a lack of focus on issues such asaesthetics or manufacturing technology which may ultimatelydetermine the success of the product or system. Any lack of a

broader awareness of the overall context within which the mech-atronics approach is being deployed is therefore likely to be detri-mental both to outcomes, and to an outsiders view of the nature ofmechatronics.

4. Design issues in mechatronics (and elsewhere)

As was suggested in the introduction, the breadth of mecha-tronics and the range of engineering domains with which it is asso-ciated requires that within the context of the paper a specific areamust be chosen in order to develop the discussion. As was indi-cated earlier engineering design was chosen for this purpose as itis believed that it presents the most complex challenges and argu-ments relating to the future role and contribution of mechatronics.Similar arguments could however be developed for any of the in-stances identified in Table 1, and it must also be acknowledgedthat this table is not complete or comprehensive. Some of the is-sues presented in the following sections, as for instance the impor-tance of establishing robust communications across a design team,have already been introduced and the intent here is to give moredetailed consideration to specific points.

4.1. The engineering design process

As technologies expand they provide additional capacity, capa-bility and functionality to the designer, leading to a requirementfor new and novel tools to support design thinking and integrationat all stages in the design process and the effective integration ofsuch tools with more function oriented design tools, as for instance

3D Thinking3D

Computer AidedEngineering

Product supportmanuals

Shopfloorassembly aids

Product DataManagement

Automatic generation of2D drawings (if wanted)

Integration withdiagnostic control andfeedback systems

Computer AidedManufacturingIntegration

Performancechecking - FEA

Assemblychecking

Fig. 8. 3D-CAE and business integration [84].

D. Bradley / Mechatronics 20 (2010) 827–841 833

those associated with detailed mechanical design and analysis.Such tools aim not to simply manage the details of the design pro-cess, but to underpin the associated thinking by helping users withthe identification of alternative solutions. This is particularlyimportant as the various aspects and stages of the design processbecome more tightly linked, as for instance through the need toevaluate the manufacturing process through the employment ofDesign for Manufacture and Assembly tools and methods at theconceptual stages of design.

Figs. 7 and 8 and Table 4 illustrate some of these relationshipswithin the context of the overall design flow. Together, these showthat as the design progresses, so the tools progressively add detailto the information passed down from the earlier stages of thatprocess.

In looking at this linkage, it perhaps needs to be considered thatthe development of engineering design understanding is, almost bynecessity, retrospective in that it looks at what has been done toobtain an effective solution, and then analyses and interprets thisto arrive at best practice which can then be deployed in future de-sign activities. There is also within engineering design a balance, aswell as a conflict, between the theoreticians, who seek to under-stand the processes by which a successful and effective design isachieved, and the pragmatists, who are primarily concerned withachieving effective solutions in response to identified need. As sug-gested by Fig. 9, the balance between these two different aspects ofthe design process, supported by the effective use of appropriatetools to enhance communication and understanding, perhapsshould be considered as a symbiotic process based around effectiveinformation exchange.

Within the context of mechatronics, such linkages can be foundin a variety of application domains ranging from manufacturing tovehicle systems and domestic products, further illustrating thediversity of application of the mechatronics concept.

4.2. Communication

Referring to Fig. 10, it has often previously been suggested that:

ProjectDefinition

IdeasGeneration Ev

Project ManagementTools

i.e. Microsoft Office

ContinuGeneral

Specialist

Visualisationi.e. Photoshop, Illustrator,

etc.

Distillation of technicalinformation into form

understandable by allstakeholders

Develop understanding andallow expression of ideas inappropriate forms andlanguage

Simulationi.e. MatLAB/Simulink,

Dimola, 20Sim

CAD Tooli.e. AutoCAD, Pro

etc.

Fig. 7. Design su

� Mechanical Engineers think in terms of physical forms andmotions.� Electrical Engineers think in terms of signals and circuits.� Software Engineers think in terms of logic and syntax.

However, such a simplistic division based on technology, whileperhaps initially having some justification, has been superseded inmany, but certainly not all, instances by approaches structured, ashas already been suggested, around methods such as concurrentengineering which recognise such differences and put in placemechanisms to deal with them. Such approaches also place anemphasis on ensuring effective communication not only withinthe design team but also with prospective specifiers and users [38].

There however remains the need to provide effective tools tosupport the ability to work with, and hence to communicate, ab-stract concepts as part of the design process. This perhaps impliesa need to provide means of ensuring an understanding across spe-cialisms through a combination of ontological forms, both linguis-tic and symbolic, together with relevant syntactical and semanticstructures to support a common meaning.

aluation ConceptDevelopment Detailing

ing role throughout project

Increasing sophistication and detail of models

Increasing sophistication and detail

Interchange

sEngineer,

Interchange

Analysisi.e. Finite Element,

Workflow, etc

Interchange

Increasing detail

Increasing detail

pport tools.

Table 4Activities in the product development process.

Market Product development stagesSpecification Concept design Detail design Manufacture

TasksMarket analysis Develop Product Definition

Statement (PDS)Generate, select and embodyconcept

Detail concept Optimise design formanufacture

InputLegislation, reports, competitive products,

statistics, market dataMarket analysis results PDS document Layout drawing Detailed drawing

Tools/approachesUser behaviour capture tools Objectives tree Brainstorming Performance

specification methodsSimulation and computeranalysis

– Parametric analysis Competitive benchmarking Sketching and rendering– Needs analysis Comparative analysis – Decision tools– Matrix analysis Word processors – Weighted objectives tree 3D modelling Laboratory experiments

Spreadsheets – QFD Finite Elementmodelling

Design for manufacture

– Morphological chart Engineering analysis Process planning2D draughting Process simulation

InformationUser observations Performance of competing

products‘Standard’ functions (i.e.common mechanisms)

Standard partcatalogues

Available manufacturingprocesses and facilities

Market surveys Material databasesForecasts and trends User specifications

Comparative analysis Manufacturer’s on-line catalogues

Comparative costs

Details on competing products DiscussionPatent database

OutputMarket analysis results PDS document Layout drawing Detailed drawing Production plan

TheoreticianReviews design process and

outcomesIdentifies methods andgenerates procedures

Establishes good practiceRefines theories

PragmatistEmphasis on problem solvingSelects, uses and refinesmethodsGenerates solutionsEstablishes practice

Fig. 9. Approaches to design.

Fig. 10. Communications issues.

834 D. Bradley / Mechatronics 20 (2010) 827–841

Referring specifically to concept design, this is generally under-taken in a collaborative setting founded on and based around dis-cussion [39–42]. Although exposure to previous solutions can insome instances result in a fixation on a particular approach [43],

access to relevant information, principles, exemplars and contextall support the creation of robust design concepts by acting asstimuli for discussion [44].

4.3. Artificial intelligence and mechatronics design

Despite the availability of a wide range of tools to support de-sign thinking as was suggested earlier by Fig. 7, the basic problemof managing communications between domain specialists remainsin place. There is a specific need to support specialists from one do-main in the early identification of potential solutions from otherdomains in a way that then enables the relevant domain expertto provide effective input. One approach to achieving this has beenthrough the use of a case-based reasoning approach [45,46] inwhich the system guides the user towards either existing solutions,the cases, or to the generation of outline solutions which can thenbe taken to the domain expert for refinement.

Consider also the design environment of Fig. 11 in which func-tional decomposition tools are used to support the mapping of thedecomposed system onto the relevant hardware. For instance, takethe filter hierarchy of Fig. 12. The top level of this hierarchy con-tains information common to all filters while the progressive lower

Design Environment

FunctionalSimulation

ImplementationLibraries

FunctionalDecomposition

Mapping toHardware &

Software

Costing &Documentation

DesignInformation

Simulation

HardwareDevelopment

SoftwareDevelopment

ElectronicDevelopment

EnclosureDesign

Fig. 11. Structuring the design environment [85].

D. Bradley / Mechatronics 20 (2010) 827–841 835

levels then contain more detailed information specific to the retrie-val category. The bottom level is then the instantiation of the spe-cific filter. Each instance thus inherits information from the toplevel ‘‘filter” along with features from the associated subclasses.

This structure can be decomposed as shown in Fig. 13, estab-lishing the major high-level processes and their relationships. Fur-ther decomposition then allows the detail of the individualprocesses to be defined. The associated data dictionaries containthree elements; a Name field which specifies the flow or group offlows to which the entry corresponds, the Form field which identi-fies, where appropriate, the variable to be used as the informationcarrier for the flow and a description of the flow, provided for thebenefit of the designer and intended as purely descriptive. The usercan then define the design requirements and application criteriafor the filter when the system will then return the best-fit casesas in Fig. 14.

4.4. Mechatronics and systems engineering

A feature of many mechatronic systems is that the design per-spective is inherently scalable. Consider for instance a manufactur-

Equiripple Least-squares Window Butterwor

ElChebyshev2Chebyshev1Butterworth

BanHighpassLowpass

Filter

Passive Active

BlackmanBartlettKaiserChebyshev

Fig. 12. Filter hierarchy, Butt

ing environment such as that shown in Fig. 15 in which a factorywide system, a manufacturing cell and an individual machine toolor robot are represented. This environment may then be redrawnin the form of the structured graph of Fig. 16 in which each levelis represented by a series of nodes linked by a communicationsnetwork. Structurally therefore, each level in the system representsan individual mechatronic system, with higher levels in the systembeing formed from the integration of a number of lower levelsystems.

This hierarchical structure also reflects the nature of the tasksinvolved at each of the individual levels within the overall system.At the lowest, or device, level the emphasis is implicitly on achiev-ing specific levels of functionality and performance. Progressingupwards through the system, the emphasis shifts from the perfor-mance of the individual devices, to the integration of a number ofsuch devices as part of a larger system. Thus there is a move awayfrom the detailed design and operation of these devices to themanagement of the information infrastructures required toachieve overall system functionality and performance.

Such shifts are also associated with changes in the operationaltime frame which may range from milliseconds at the lowest, ormachine, level to hours, days or weeks at the highest, human, lev-els. These time shifts are also associated with changes in the natureof the associated information. Consider the situation of Fig. 17which illustrates the flow of procedural, the WHAT, and processdata, the HOW. Each of the layers in this system represents an inte-grated process such as a the strategic or factory level, a manufac-turing cell, an individual machine tool or robot or an individualactuator or sensor. There is then a requirement for the manage-ment of the procedural information as it flows up and down thesystem to match the information needs at each of the process lev-els. In this model, human interaction with the system decreasesfrom top to bottom, the highest levels being those associated withstrategic decision making and the lowest with the operation ofindividual devices or components.

In the context of such systems, whether they be factories, air-craft, vehicles, or indeed any systems based device, product or pro-cess, is it perhaps therefore the case that the lower levels of thehierarchy are those where the mechatronics approach has had amajor impact, while at the higher levels it is systems integration,and hence systems engineering, that is more important?

th Chebyshev1 Chebyshev2 Elliptic

IIRFIRliptic

Band-Stopd-Pass

Digital

TriangularHannHamming

erworth block is shaded.

Designa filter

1.3

Finddesign

1.4

Optimisethe design

1.5

Completedesigns

Modifythe design

1.6Design tools

UserUser

User

Link_to_app.

Link_to_type/tech.

Simulated_design

Updated_design

New_frequency

Frequency_ range

User

SelectApp .1.2

Selecttype/tech

1.1

User

Filter_type/tech._display

Filter_type/tech._input

Filter_app._displayFilter_app._input

New_type_to select(1)

New_type_to select(2)

Type/tech._information

New

_app

._to

sel

ect

User_inputs(1)

Design_display

Tool

_req

uest

Tool_request

Design_information C

riter

ia_d

ispl

ay

Crit

eria

_inp

uts

Search

_req

uest

Desig

n_re

ques

tDe

sign_

fit

Designs_listDesign_selectionD

esign_match

Designtools

Simulated_design

Tool_request

Fig. 13. First Level Decomposition of the Filter Design System.

Fig. 14. Search results.

836 D. Bradley / Mechatronics 20 (2010) 827–841

Actuators Sensors

Factory-wide Network

Manufacturing Cell

Robot or Machine Tool

Fig. 15. A simplified manufacturing hierarchy.

Factory-Wide Network

Manufacturing Cell

Machine Tool or Robot

Each node represents amanufacturing ce with theinterconnection provided by thefactory wide network

Each node represents an individualmachine tool, robot or handlingsystemn with interconnectionprovided by the local network

Each node represents anactuator, sensor or controllerwith interconnection provided bythe machine network

Fig. 16. Manufacturing hierarchy.

Proc

edur

al In

form

atio

n- t

he W

HA

T

Process Layer

Process Information- the HOW

Data Translation &Interpretation betweenProcess Layers

Mac

hine

bas

edsy

stem

sH

uman

bas

edsy

stem

s

Mec

hatro

nics

Syst

emEn

gine

erin

g

Fig. 17. Information flows.

D. Bradley / Mechatronics 20 (2010) 827–841 837

5. Mechatronics education

Since its inception, mechatronics has, in a variety of forms andformats, established itself internationally as a discipline withinengineering science education and there are increasing numbersof courses worldwide carrying a mechatronics label. Such coursescannot necessarily be considered as having significant commonal-ity in either approach or content other than at a basic level as theyeach tend to reflect the local and national interests where thecourse is being developed and implemented. Within that context,is the very flexibility and adaptability of the mechatronics conceptworking to its advantage in terms of course structures, whilst add-ing to the diversity of perception as to what, in the widest sense,mechatronics represents?

Whatever the context, in the development of mechatronics edu-cation, the concern in course design has always been that achievingan appropriate balance between the provision of the necessarydepth of understanding of the core technologies and disciplineswith the ability to develop solutions which integrate those tech-nologies. This may be compared to a subject based approach toengineering science education where the emphasis is on ensuringa depth of understanding within the subject area.

Is it therefore then the case that the education of a mechatron-ics engineer should place an emphasis on the ability to work acrossand between individual areas of technology? This is not howeverto suggest that a mechatronics educated engineer is not requiredhave to have a depth of knowledge in specific specialist areas,rather that such depth is balanced by an understanding and appre-ciation of the contributions of other areas of technology as is sug-gested by Fig. 18.

Should therefore the achievement of a balanced programme ofmechatronics education be based around ensuring that individualsare provided with sufficient depth in at least one area of technol-ogy in order to allow them to make an effective contribution tothat area, whilst ensuring the breadth of understanding necessaryto give them credibility with respect to other subject specialists?Consequently, is the key challenge facing mechatronics coursedesigners then that of ensuring that there is an appropriate balancebetween depth and breadth within the course as well as providingopportunities to enable students to practice integration?

Though mechatronics emphasises integration, it may also beperceived as encompassing a number of themes such as design,manufacturing or automation. In relation to course development,the choice of theme is generally dictated by a number of factorsincluding:

Dep

th

Subject Area

Overlap

Dep

th

Subject Area

MechatronicsEngineer

(a) Specialist education (b) Mechatronics education

Fig. 18. Balance of technical expertise for specialist and mechatronics educatedengineers. (a) Specialist education, and (b) mechatronics education.

838 D. Bradley / Mechatronics 20 (2010) 827–841

� The backgrounds and interests of the staff involved in teachingthe course.� Industrial requirements, both locally and nationally.� Student perceptions and interests.� Availability of resources, particularly human and financial.� Research activity.

While it is unlikely that any one of these considerations willdominate course development to the exclusion of others, any oneof these factors may well be the defining influence for a particularprogramme or course.

For instance, resource implications will often mean that teach-ing of specialist material will require that mechatronic engineersare incorporated as part of a larger group of subject specialistsfor this purpose, with the courses then being structured to meetthe needs of the subject specialists rather than the mechatronicsstudents. Also, the increasing modularisation of programmes cantend to mitigate against the ability to introduce the necessary inte-grating material, particularly where modules are seen as having tobe complete and entire within themselves.

In light of the above challenges, how might the designers of amechatronics course respond? What is clear is that they are facedwith a number of questions including:

� Should a theme be chosen or should it emerge as a result of thelocal expertise and enthusiasms?� How are the integration aspects of mechatronics to be intro-

duced and managed?� How are external requirements, as for instance the Bologna

Agreement in Europe [47,48], to be managed?� What is the local market for graduates and is the proposed

course going to meet those requirements?

As a consequence of the above, has mechatronics suffered froman identity crisis both within the academic community and else-where, and is this likely to continue to be the case given the diver-sity of approaches and emphasis that are found within thecommunity?

Yet there is no doubt that there is a need for graduate engineerswith the particular integration skills that are provided by a mech-atronic education.

The key challenge facing mechatronics course designers there-fore remains that of achieving an effective balance between therequirement for detailed knowledge and engendering the abilityto act in an integrating role in a wide range of engineering environ-ments. The achievement of this balance is further subject to awhole range of pressures ranging from the rapid advance of tech-nology to external factors impacting on course management anddesign such as the moves to implement sustainable systems or in-crease student mobility. The underlying precepts presented hereare however likely to remain as a constant for course designersand developers.

4 Formerly the World Commission on Environment and Development and chairedby the then Prime Minister of Norway, Gro Harlem Brundtland.

5 ICLEI – Local Governments for Sustainability.

6. Challenges

It is clear that engineering design and its mechatronic compo-nent will need to continue to adapt to meet and respond to a rangeof challenges in areas such as energy systems, transport, healthcare, medicine and manufacturing. Indeed, could it be argued thatthe achievement of sustainable systems in all of these, and other,areas will depend on the ability to integrate a mechatronic ap-proach to system design and development with correspondingdevelopments in areas such as materials technology which will im-pact not only on new product concepts, but also on the way theyare made?

Such a shift in perspective will in turn cause present consider-ations of Design for Manufacture and Assembly, which are oftenin conflict with the requirements of design for disassembly ormaintenance, to be brought into question. Consider for instancethe use of snap connectors for joining components. These are easyto assemble but can make access problematic without the destruc-tion of the item in question.

6.1. Mechatronics and a sustainable future

In the 1987 report of the Brundtland Commission, Our CommonFuture, sustainable development was defined as [49]:

‘Development that meets the needs of the present without compro-mising the ability of future generations to meet their own needs’.4

This requirement to embbed sustainability within future sys-tems in emphasised by the ratification in 2007 of the United Na-tions and ICLEI5 TBL standard for urban and communityaccounting. Similar UN standards apply to natural capital and humancapital measurement to assist in measurements required by TBL[50–53].

Given the significance of these developments, is it implicit thatmechatronics must change and adapt itself to encompass issues ofsustainability within its conceptual remit? Assuming that this isthe case, what then are the implications for the design, develop-ment and implementation of future mechatronic systems?

6.2. Developments in mechatronic applications

Some of the potential areas where mechatronics could poten-tially have a major impact in relation to future applications aresuggested in the following sections.

6.2.1. ManufacturingMechatronics is often associated with robotics and factory sys-

tems. However, systems that move, machine and assemble are per-haps only classifiable as such by the degree to which theyincorporate adaptability and agility within their operation? Asmanufacturing systems have evolved to incorporate increasingnumbers of semi and near autonomous elements, mechatronic sys-tems have played a role in applications such as assembly, machin-ing, inspection, dangerous material handling and disassembly.

With the introduction of ‘manufacture on demand’ strategies,buyers seek increased opportunities for customisation. This hasnecessitated an agility of operation, often involving autonomouslyreconfigurable machine tools [54] and dynamic decision making[55] as an integral part of the process, enabling manufacturinggroupings to be created [56] in response to demand. As a conse-quence, manufacturing cells increasingly provide a variety of jobfunctions on a part-by-part basis. The resulting organisationaland operational complexity has in turn been supported by theintroduction of strategies such as game theory [57] and self-orga-nisation [58,59].

Other areas of production where mechatronic systems can beconsidered to have impacted is with respect to those environmentswhere it is either unsafe or inconvenient for humans to work. Thisincludes the movement of materials [60], the handling of toxic andradioactive materials and maintenance in heavily polluted envi-ronments [61].

There is also an increasing move, driven in part by legislation onwaste disposal and management as well as on recycling, to in-crease the emphasis on design for disassembly and component re-

D. Bradley / Mechatronics 20 (2010) 827–841 839

use. Is this perhaps also an area where mechatronics will have agrowing, and significant, role to play?

6.2.2. TransportIs this a key area where mechatronics is likely to significantly

impact on and influence design, development and operation? Forinstance:

6.2.2.1. Rail. The further development of tilting trains, active sus-pensions, driven and steered wheelsets and traction and brakingcontrol are all likely to feature to some degree in future train sys-tems along with enhanced drive technologies and controller strat-egies [62]. Other potential areas of development include high-speed trains and the use of maglev technologies [63,64].

6.2.2.2. Road transport. The move towards hybrid vehicles and theuse of fuel cell technology [65] as well as an increasing range ofon-board systems for driver assistance, safety and security andvehicle and engine management. An example of such thinking isthe Siemens eCorner ‘smart wheels’ concept. This uses a hub motorlocated inside the wheel rim together with an electronic wedgebrake whose pads are driven by electric motors. An active suspen-sion and electronic steering replace conventional hydraulic sys-tems, supporting advanced drive-by-wire concepts [66].

6.2.2.3. Aircraft. Aircraft, the growth of air transport and the impacton the environment is undoubtedly one of the most contentiousareas in which mechatronics is likely to play a role. Issues includethe design of aircraft that are quieter and more fuel efficiency andwith a lower environmental impact than present aircraft [67–70].

6.2.3. Energy technologiesThe deployment and use of alternative energy sources such as

wind and wave power [71,72], the introduction micro combinedheat and power (microCHP) systems [73] heat pumps and fuel cellsas well as new generations of appliances and energy managementoptions within the home are all going to be influenced by mecha-tronic approaches to their design operation and control.

6.2.4. HealthInstances here include the development of enhanced and intel-

ligent prostheses for both the upper and lower limbs [74–77], theintroduction of systems to support the rehabilitation of a range ofmedical and clinical conditions [78,79], the provision of new surgi-cal methods and techniques involving the deployment of roboticsystems and telecare, telemedicine and telehealth strategies basedon the introduction and deployment of enhanced sensors, net-working and data analysis [80]. In each of these and related areas,is the deployment of a mechatronic approach is likely to be key inachieving robust, reliable and effective systems?

6.2.5. MaterialsThe choice of materials is becoming increasingly important in

relation to the design and operation of systems of all types, as forinstance in the increased use of composite materials in vehiclessuch as cars and aircraft as well as in consumer products. The pro-vision of new types of materials has itself made it possible to de-velop these products in a way which supports the generalmechatronic concepts of integration at the systems level [81–83].This includes technologies such as smart fabrics which can incor-porate a sensing function for health related issues such as monitor-ing people working in hazardous environments such as thoseinvolving high ambient temperatures.

6.3. Potential for technological impact

Developments in technology are going to continue to drivechanges within the design process and to impact upon the designprocess. For instance, the development of low cost network sensorscreates opportunities to develop new approaches to informationcollection and management and the increasing availability ofMEMS devices is likely to force a radical rethink of the approachto many areas of application, supporting the integration of mea-surement and data processing throughout the system.

Many of these system components will incorporate significantprocessing power in their own right, opening up the opportunityto create not only a distributed sensor network, but of using thosesame sensors as part of a distributed and parallel processing array.It is not therefore inconceivable to envision a system such as avehicle relying on such a distributed array to manage all its on-board functions, with the added benefit of multiple redundancyin case of a failure of component part.

Developments in materials and actuators are also going to im-pact on the approach to the design of a wide range of systems.For instance, neural interface chips such as those being developedat the University of Utah and elsewhere could support the design,development and implementation of a new range of prosthesis byallowing a level of connectivity between the original nerve bundleand the prosthetic to be re-established. This brings with it theprospect of providing neural feedback on the position and behav-iour of the prosthetic limb, perhaps even restoring an element ofproprioception and kinesthesia to limb movement.

7. Discussion

In the introduction it was stated that the key aim of the paperwas to raise questions as to the current and future direction andstatus of mechatronics as an engineering discipline, or perhaps adesign philosophy structured around integration. Or indeed ifsome other direction or directions of development are likely orappropriate. In this context, it is perhaps possible to reduce the dis-cussion of the previous sections to the key question ‘‘Does mecha-tronics still remain significantly different when compared to otherapproaches to system integration?”

While it is the intent of the author that each reader formulatestheir own response to this and the other questions and issuesraised, there are a number of comments that might perhaps bemade in support of the discussion that it is hoped to engender.

For instance, while it is possibly the case that mechatronics hasto a significant degree been integrated with and incorporated with-in mainstream engineering design methods and strategies, is thisbecause other areas of engineering design have learnt about inte-gration from mechatronics as part of the natural transfer that takesbetween design practice and design theory and vice versa?

Further, when mechatronics was first suggested, was it repre-sentative of a wider shift in thinking about systems and integrationwith in the overall engineering design process that was takingplace around that time, as expressed by the emergence of the pre-cepts of concurrent engineering? When combined with such newand different ways of thinking about the management and organi-sation of the design process, and supported by an evolving techni-cal capability, this has led over the last 40 years to thedevelopment and implementation of a wide range and variety ofproducts and systems which have technical integration at theircore. Having thus initially been driven by a realisation that changesin technology required a shift in thinking about product design anddevelopment, does mechatronics still retain that ability to bring to-gether the best from a wide range of domains, and not exclusivelytechnical domains, to create further systems?

840 D. Bradley / Mechatronics 20 (2010) 827–841

Is therefore the case for the future of mechatronics that it rep-resents a continuing coming together of the ways in which com-plex and integrated systems are conceived and envisioned andimplemented? As a consequence, have members of the mechatron-ics community simply to live with the name, despite the fact thatthe original motivation for its construction has perhaps long sincegone?!

8. Conclusions

The past 40 years have seen significant changes in the capacityand capability of the technologies around which mechatronics wasinitially structured, conceived and developed. In this same period,new tools, technologies and techniques have been put in place tosupport the design and development of a wide range of oftenincreasingly complex engineering systems. The period has alsoseen a growth in the range of activities and disciplines encom-passed by the mechatronics banner. The premise on which the pa-per is based is therefore that of a need to revisit the mechatronicsconcept, not with the aim of redefining this, if indeed this werepossible without over-constraining activity, but of repositioningit in line with the various technical and organisational threads withit could, or should, be associated with over the next 40 years.

The issues for debate arising from the paper are not thereforewhether mechatronics has made a significant contribution to thedesign, development and implementation of a wide range of engi-neering systems but how the concepts and structures which haveunderpinned the 40 years of development since the mechatronicswas put in place are to change and evolve to accommodate currentand future developments. These issues are the underlying consid-erations and concerns in putting forward the background, argu-ments and questions embedded throughout the paper.

Having been involved in mechatronics for some 25 years, thepaper reflects an ongoing personal debate regarding issues suchas achieving sustainability through mechatronics and its evolutionto encompass developments in technology, as for instance associ-ated with MEMS technology. Unfortunately, this personal debatehas not resulted in a specific outcome other than a belief that itis increasingly necessary for the wider mechatronics communityto recognise these issues.

Acknowledgements

The above represents a highly personal view resulting frommore than 20 years of working in the field of mechatronics. Thedevelopment of the underpinning arguments would not howeverhave been possible without the involvement, in some cases overmany years, of colleagues, research associates and research stu-dents. These include, but not exclusively, in no particular orderand with apologies to those who space precludes me from men-tioning; Michael French, David Dawson, Derek Seward, Tony Dorey,Bill Scarfe, John Millbank, Nouredine Bouguechal, Stephen Harris,Allan Parker, Andrew Wodehouse, Camilo Acosta-Marquez, Samirel-Nakla, Simon Brownsell, Sa’ad Mansoor, Jacob Buur, MyrupAndreasen, Lars Hein, Glen Bright, Dave King, Capel Aris, GlynnJones, Roger White, Gareth Williams, Dewi Jones, Richard Walters,Rob Bracewell, Mark Hawley, Sue Mawson, Pam Enderby and DavidRussell plus various assorted masters students, members of theMechatronic Forum in the UK and friends and colleagues else-where throughout the world.

References

[1] Bradley DA. Mechatronics – an established discipline or a concept in need ofdirection? In: Mechatronics2000, Atlanta (CDRom only); 2000.

[2] //mechatronics.colostate.edu/definitions.html (accessed 20.01.10).

[3] Tomizuka M. Mechatronics: from the 20th to 21st century. Control Eng Pract2002;10(8):877–86.

[4] Harashima F, Tomizuka M, Fukuda T. Mechatronics – what is it, why, and how?IEEE/ASME Trans Mech 1996;1:1–4.

[5] Kyura N, Oho H. Mechatronics – an industrial perspective. IEEE/ASME TransMech 1996;1:10–5.

[6] Kenjo T, Lorriman J. Creating a new paradigm – mechatronics and futurechallenges, IET; 2009. <kn.theiet.org/magazine/rateit/control/mechatronics.cfm> (accessed 1.02.10).

[7] Brown A. Who owns mechatronics. Mechanical engineering, American Societyof Mechanical Engineers, June; 2008. <www.memagazine.org/contents/current/features/whoowns/whoowns.html> (accessed 03.02.10).

[8] Brooks J. Dreadnought gunnery and the battle of Jutland – the question of firecontrol. Routledge; 2005.

[9] King AD. Inertial navigation – forty years of evolution. GEC Rev 1998;13(3):140–9.

[10] //biomech.media.mit.edu/publications/publications.htm (accessed 24.06.10).[11] http://www.ric.org/research/centers/smpp/labs/biomechdev/Biomechatronics.aspx/

(accessed 24.06.10).[12] //bss.ewi.utwente.nl/research/biomechatronics/index.html/ (accessed 24.06.10).[13] www.azonano.com/news.asp?newsID=4479 (accessed 24.06.10).[14] www.mems-exchange.org/MEMS/what-is.html (accessed 24.06.10).[15] Scarfe WR. Flight systems engineering. British aerospace, personal

communication.[16] www.hq.nasa.gov/office/pao/History/computers/Part1.html (accessed 02.02.10).[17] Habib MK. Interdisciplinary mechatronics engineering and science. problem-

solving, creative-thinking and concurrent design synergy. Int J MechatronManufact Syst 2008;1(1):4–22.

[18] Allen RG. Mechatronics engineering: a critical need for this interdisciplinaryapproach to engineering education. In: Proc IJME – INTERTECH conf, paperENG 205-085; 2006.

[19] Millbank J. Mecha-what? Mechatronics forum newsletter, Summer; 1993.[20] Crossing MooreG. Crossing the chasm: marketing and selling high-tech

products to mainstream customers. New York: HarperCollins; 1991.[21] Rogers E. Diffusion of innovation. The Free Press; 1995.[22] Thrun S et al. In: Buehler M, Iagnemma K, Singh S, editors. Stanley: the Robot

that won the DARPA grand challenge, the 2005 DARPA grandchallenge. Springer; 2006.

[23] Isermann R. Mechatronic systems – innovative products with embeddedcontrol. Control Eng Pract 2008;16(1):14–29.

[24] www.sunspotworld.com (accessed 24.08.10).[25] Bradley DA. The what, why and how of mechatronics. IEE J Sci Educ

1997;6(2):81–8.[26] Craig K. Is anything really new in mechatronics education? IEEE Robot Autom

Mag 2001;8(2):12–9.[27] Bradley DA. What is mechatronics and why teach it? Int J Electr Eng Educ

2004;41(4):275–91.[28] Siegwart R. Grasping the interdisciplinarity of mechatronics. IEEE Robot

Autom Mag 2001;8(2):27–34.[29] Doppelt Y. Assessment of project-based learning in a mechatronics context. J

Technol Educ 2005; 16(2). http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.145.3330&rep=rep1&type=pdf (accessed 24.08.10).

[30] French MJ. Conceptual design for engineers. Springer-Verlag; 1998.[31] <http://www.iabg.de/presse/aktuelles/mitteilungen/200409_V-Model_XT_en.php>

(accessed 24.08.10).[32] Coughlin JF. Not your father’s auto industry? Aging, the automobile, and the

drive for product innovation. Generations 2004;28(4):38–44.[33] Hitchcock DR, Lockyer S, Cook S, Quigley C. Third age usability and safety – an

ergonomics contribution to design. Int J Human–Comput Stud 2001;55(4):635–43.

[34] Styhre A, Backman M, Börjesson S. YCC: a gendered carnival? Project work atVolvo Cars. Women Manage Rev 2005;20(2):96–106.

[35] http://www.defenseindustrydaily.com/f22-squadron-shot-down-by-the-international-date-line-03087/ (accessed 02.02.10).

[36] http://www.newscientist.com/article/mg19626359.900-the-doh-of-technology.html?page=2 (accessed 02.02.10).

[37] http://www.in.tum.de/~huckle/bugse.html (accessed 20.01.10).[38] Wodehouse A, Bradley DA. Gaming techniques and the product

development process: commonalities & cross applications. J Des Res2006;5(2):155–71.

[39] Cross N. Engineering design methods, strategies for product design. John Wiley& Sons; 1994.

[40] Pahl G, Beitz W. Engineering design, a systematic approach. Springer;1995.

[41] Pugh S. Total design. Addison-Wesley; 1991.[42] Ulrich KT, Eppinger SD. Product design and development. McGraw-Hill;

1995.[43] Smith SM, Kohn NW, Shah J. What you see is what you get: effects of

provocative stimuli in creative invention. In: NSF int workshop on studyingdesign creativity, Provence; 2008.

[44] Benami O, Jin Y. Creative stimulation in conceptual design. In: Joint ASME 2002design engineering technical conference & computer and information inengineering conference, Montreal; 2002.

[45] El-Nakla S, Bradley DA. Case-based reasoning and conflict resolution insupport of the design of mechatronic systems. In: 9th Mechatronics forumconference; 2004. p. 123–30.

D. Bradley / Mechatronics 20 (2010) 827–841 841

[46] El-Nakla S, Bradley DA. Case-based reasoning in the design of mechatronicsystems. In: 11th Mechatronics forum conference, electronic publication;2008.

[47] http://www.coe.int/t/dg4/highereducation/EHEA2010/BolognaPedestrians_en.asp#P132_13851 (accessed 03.02.10).

[48] en.wikipedia.org/wiki/Bologna_process (reviewed 03.02.10).[49] Bruntland G. Our common future: the world commission on environment and

development. Oxford University Press; 1987 (<http://www.anped.org/media/brundtland-pdf.pdf>) (accessed 24.08.10).

[50] Elkington J. Cannibals with forks: the triple bottom line of 21st centurybusiness, Capstone; 1999.

[51] Elkington J. Towards the sustainable corporation: win–win–win businessstrategies for sustainable development. Calif Manage Rev 1994;36(2):90–100.

[52] Brown D, Dillard J, Marshall RS. Triple bottom line: a business metaphor for asocial construct. Portland State University, School of Business Administration;2006. http://www.recercat.net/bitstream/2072/2223/1/UABDT06-2.pdf(accessed 24.06.10).

[53] http://www.goethe.de/ges/umw/dos/nac/den/en3106180.htm (accessed 24.06.10).[54] Bi ZM, Lang SYT, Shen W, Wang L. Reconfigurable manufacturing systems: the

state of the art. Int J Prod Res 2008;46(4):967–92.[55] Shu-Hsien Liao. Expert system methodologies and applications – a decade

review from 1995 to 2004. Expert Syst Appl 2005;28(1):93–103.[56] Katz R. Design principles in reconfigurable machines. Int J Adv Manufact

Technol 2007;34:430–9.[57] Qiu R, McDonnel P, Joshi S, Russell DW. A heuristic game theoretic approach to

resource sharing in reconfigurable manufacturing. Int J Adv Manufact Technol2005;25(1–2):78–87.

[58] Rao A, Gu P. Expert self-organizing neural network for the design of cellularmanufacturing systems. J Manufact Syst 1994;13(5):346–59.

[59] Kubota N, Fukoda T. Structured intelligence for self-organizing manufacturingsystems. J Intell Manufact 1999;10(2):121–33.

[60] Durrant-Whyte HF. An autonomous guided vehicle for cargo handlingapplications. Int J Robot Res 1996;15(5):407–40.

[61] Micire MJ. Evolution and field performance of a rescue robot. Int J Field Robot;2008. robotics.cs.uml.edu/fileadmin/content/publications/2008/jfrExample.pdf (accessed 3.02.10).

[62] Goodall RM, Kortüm W. Mechatronic developments for railway vehicles of thefuture. Control Eng Pract 2002;10(8):887–98.

[63] Hyung-Woo Lee, Ki-Chan Kim, Ju Lee. Review of maglev train technologies.IEEE Trans Magn 2006;42(7):1917–25.

[64] Vuchic VR, Casello JM. An evaluation of maglev technology and its comparisonwith high speed rail. Transport Quart 2002;56(2):3–9.

[65] Emadi A, Rajashekara K, Williamson SS, Lukic SM. Topological overview ofhybrid electric and fuel cell vehicular power system architectures andconfigurations. IEEE Trans Veh Technol 2005;54(3):763–70.

[66] fp.is.siemens.de/traffic/en/news/itsmagazine/html/0702/pdf/artikel/englisch/Drive-by-wire_e.pdf (accessed 3.02.10).

[67] Green JE. Future aircraft – greener by design? Meteorol Z 2005;14(4):583–90.

[68] Åkerman JA. Sustainable air transport – on track in 2050. Transport Res Part D:Transport Environ 2005;10(2):111–26.

[69] Thomas C, Raper D. Sustainable mobility and the air transport industry –comments on the European commission’s views. Air Space Eur 2000;2(3):13–6.

[70] Daviss B. Green sky thinking. New Sci 2007;193(2592):32–8.[71] Ackermann T. Wind power in power systems. John Wiley & Sons; 2005.[72] Clément A et al. Wave energy in Europe: current status and perspectives.

Renew Sustain Energy Rev 2002;6(5):405–31.[73] Peacock AD, Newborough M. Impact of micro-combined heat-and-power

systems on energy flows in the UK electricity supply industry. Energy2006;31(12):1804–18.

[74] Biddiss E, Beaton D, Chau T. Consumer design priorities for upper limbprosthetics. Disabil Rehabil Assist Technol 2007;2(6):346–57.

[75] Ohnishi K, Weir RF, Kuiken TA. Neural machine interfaces for controllingmultifunctional powered upper-limb prostheses. Expert Rev Med Dev2007;4(1):43–53.

[76] Bonato P. Advances in wearable technology and applications in physicalmedicine and rehabilitation. J NeuroEng Rehabil 2005;2(2). doi:10.1186/1743-0003-2-2 (accessed 24.08.10).

[77] Sup F, Varol HA, Mitchell J, Withrow TJ, Goldfarb M. Self-contained poweredknee and ankle prosthesis. In: 11th Intl conf on rehabilitation robotics, ICORR2009, paper 0024; 2009.

[78] Riener R, Nef T, Colombo G. Robot-aided neurorehabilitation of the upperextremities. Med Biol Eng Comput 2005;43(1):2–10.

[79] Ball SJ, Brown IE, Scott SH. MEDARM: a rehabilitation robot with 5DOF at theshoulder complex. In: IEEE/ASME intl conf adv intell mech; 2007. doi:10.1109/AIM.2007.4412446 (accessed 24.08.10).

[80] Wootton R, Dimmick SL, Kvedar JC, editors. Home telehealth: connecting carewith the community. Royal Society of Medicine; 2006.

[81] Ashby MF, Bréchet YJM, Cebon D, Salvo L. Selection strategies for materials andprocesses. Mater Design 2004;25(1):51–67.

[82] Sapuan SM. A knowledge-based system for materials selection in mechanicalengineering design. Mater Design 2001;22(8):687–95.

[83] http://www.grantadesign.com/products/ces/ (accessed 3.02.10).[84] Dawson D. Personal communication; 2009.[85] Walters R, Bradley DA, Dorey AP. A computer based tool to support

electronics design in a mechatronic environment. In: Mechatronics’98,Skövde; 1998.

[86] http://authors.library.caltech.edu/5456/1/hrst.mit.edu/hrs/apollo/public/visual3.htm (accessed 2.02.10).