New Strategies for Technology Products Development in HealthCare

HealthCare Product Design, and in particular the development of bio-electronic device for diagnosis  and  monitoring,  is  usually  very  complex  because  it  concerns  many  different disciplines  (eg.  Medicine,  Electronics,  Computer  Science,  Product  Design,  etc.).  Moreover Healthcare   products   are   almost   always   used   by   many   different   actors,   for   example caregivers,  physicians,  patients  and  their  relatives.  They  can  be  therefore  defined  as multidisciplinary   products.   This    implies   great   difficulties   during   the   design   and development of new products because it is necessary to consider many different points of view, in particular without forgetting the diverse users’ needs.Healthcare products can be structured as the sum of two components: the front-end layer i.e. the visible part of them, and the back-end layer that is the hidden part of the products. The back-end layer allows the device to work reliably and efficiently from a the technical point of view, on the other hand, the front-end layer is related to user’s acceptability and functioning, so it is probably the most important characteristic to avoid usage errors.As front-end and back-end layers are strongly related, their parallel development is needed in order to test each development step with final users. This activity is only possible through fast   prototyping   of   both   components.   Both   Back-end   and   Front-end   Layers   can   be subdivided in hardware and software.

Multidisciplinary approach

If  to  develop  good  products  in  healthcare  design  requires  a  complex  knowledge,  then  a multidisciplinary team is needed.

According with Martin (2008), “medical devices are technology driven rather than resulting from  an  identified  un-meet  need”.  For  this  reason  in  the  set-up  phase  of  the  process,  the definition of a complexity map is absolutely necessary; we define this step as “problem” (i.e. the first block of the flow chart in figure 2). If theoretically many methods can be proposed to  correctly  and  completely set-up  the  problem  for  healthcare  products (Nam  et  al.  2009), generally in the real world the problem is defined by marketing office of the Company (and in this case and in the next of this paper we will assume this option), or by the medical team as the result of everyday work experience. In  this  condition,  the  first  step  is  to  define  the  design  requirements  of  the  system  and  to select  with the  team  some  fixed  points.  Fixed  points  are  fundamental  in  order  to  allow concurrent engineering development process. In this process two teams develop in parallel the back-end and front-end layers of the system. For back-end layer development, engineers are the key figures to solve the technical problems identified in fixed points. Instead, Front-end concept is designed according to the user needs collected directly from in-field  ethnographic  observations.  Actually,  in  this  stage,  the involvement  final  users  for proposal evaluation is difficult.

The  next  step  is  the  integration  of  back  and  front-end  layers.  This  integration  is  possible thanks to fast prototyping technologies (as deeper described in the next paragraph). As  Moggridge  (2006)  describes  “Early  and  often  Prototyping  makes  each  iterative  step  a little more realistic. At some point you are likely to experience that feeling that comes with a creative leap, but that is only an indication that you have moved forward in the detail of the aspect of the design that you are focusing on. You will only know that the design is good when you have tried it out with the people who will use it and found that they are pleased, excited, motivated, and satisfied with the result.”

The first phase in this context is an “expert user test”. At this stage the prototypes are not enough  defined  and  the  perception  of  the  standard  end-user  could  be  not  significant  and reliable;  for  this  reason  it’s  not  possible  to  have  a  real  “User  Experience”  but  only  tests carried  out  by  experts.  Anyway,  in  some  cases  it  is  possible  to  perform  an  “Oz  Wizard” experience  in  order  to  simulate  a  “real  experience  test”  with  end-users  through  partially operating  prototypes  that  anyway  seems  to  have  all  working  functionalities.  Then  it  is possible to collect the user’s opinion about their experience using normal interviews. Thanks  to  the  answers  obtained  from  the  interviews,  the  previous  fixed  points  can  be re- defined  and  the  design  cycle  (both  for  back  and  front-end  layers)  can  start  again.  In  this second  loop,  back-end  developers  and  front-end  designers  can  build  up  new  proposals based  on  the  first  results  of  previous  experimentation.  These  new  proposals  will  be integrated  again  with  fast  prototyping  techniques  for  the  user  involvement  tests.  The difference between this second “user test” and the first one is related to the interactivity of the prototypes. At this stage, prototypes are closer to a working product and for this reason users’ involvement in a real experience test is possible. A co-design process could start until the team arrives to positive results.

Fast prototyping

The  design,  test  and  production  of  a  robust  and  operating  prototype  is  a  work  that  can require  a  huge  quantity  of  resources,  both  in  human  efforts  and  in  time:  for  HealthCare products, this step could be also longer because of the several and strict rules governing this area    for    safety    requirements:    bio-compatibility,    electrical    safety,    electromagnetic compatibility tests are only a typical example of the technical requirements to be satisfied. Sometimes time-to-market needs becomes critical: a so long amount of resources and time could be incompatible with market’s law and can bring to the premature closure of a project. Therefore an Exit Strategy is to be always defined and verified at each step of the project. To  speed  up  the  development  process  Fast  Prototyping  can  play  a  fundamental  role.  Fast prototyping is a useful tool in product design making it possible to evaluate the interaction between final users and objects in an early stage of the development process. (Erickson 1995). Concerning product design it is possible anticipate even more the evaluation of usability and satisfaction using formal models and Wizard of Oz techniques. (Maudsley et al 1993). Fast Prototyping, also called evolutionary prototyping (for the reason that the prototype will eventually be refined to create the real product) (Crinnion 1990) is a term taken from the last years trend in software engineering in which the use of this method bring to a rapid creation of new and efficient software, compatible with the dynamic aspect of software market.This kind of prototyping involve creating a working foretype at a very early stage, after a relative fast investigation. The method used for the realization of this prototype is usually quite informal; in fact the most important factor in fast prototyping is not the quality of the final product but the speed with which the prototype is developed so as to involve users in the shortest possible time. Now technology also offer 3.D ABS printers or stereo-lithography builders, that just from the 3D draft drawings in a proper format (.dxf, .stl, ect.) can directly realize  in  a  few  hours  the  formal  prototype.  This  first  prototype  will  became  the  starting point  from  which,  through  the  use  of  expert-  and  end-user  tests,  the  developer  can  re- examine  their  expectations  and  clarify  the  requirements.  But  also  technology  developers could verify all the dimensional and mechanical issues related to the back-end layer.

For a profitable adoption of Fast Prototyping techniques in order to collect significant data from the users, the prototype has to be:

•     functional even with a minimum effort;

•    a  means  for  providing  users  a  real-like  application,  thanks  to  a  faithful  physical representation  of  the  main  parts  of  the  system  even  before  final  and  real  product implementation;

•    flexible, that is modifications require minimal effort and could be done in short time, in case tests evidence an immediate feedback for some physical features changes;

•    according to the previous point, not necessarily representative of the complete expected final product. For all the above, we can divide the Fast Prototyping phase in two parts (Figure 2):

•     Back-End layer development;

•      Front-End Concept Design.

Back-end layer development

The Back-End part consists of all the technological components of the system, i.e. specifically the hardware and the software/firmware parts. In  the  hardware  we  include electronic  circuits,  electro-mechanical  subsystem,  mechanism, connectors, fixing components and all the things that are „hard“; the software and firmware are   instead   the   computer   programs   (generally   embedded  or   “mounted”   onto   a microprocessor which can be considered the core  of the system itself) that manage all the operations  carried  out  by  the  hardware,  pre-process  data  and  communicate  or  deliver  or receive information/commands to the new software layer beyond the Front-end part.  Circuit  simulation  tools  are  now  available  to  support  the  development  through  early debugging sessions; their function is similar to  the fast prototyping techniques previously described for the physical shape development phase.

Sometimes   technological   solutions   can   be   offered   or   retrieved   from   an   open-source community; in the last decade, this “free market” has demonstrated to grow up above all among academics and since a couple of years also companies are looking with interest to these  solutions  about  open  and  free  hardware  and  software  tools,  and  about  circuit realization examples that this huge community provides. In  the  next  paragraph,  we  present  some  examples (both  for  software  and  for  hardware components)  that  can  be  useful  during  fast  prototyping  experimentation.  In  particular, regarding  the  development  of  healthcare  devices,  we  show  some  examples  focusing  on available tools that can be useful in designing for electronic biomedical devices.

Open source and free tools for hardware design

gEDA: gEDA is a set of free software applications used for electronic design   and released under  the  GPL  license(Brorson  2006).  gEDA  suite  includes  different  programs  through which the developer can design a circuit device starting from drawing the electronics circuit to the realization of the printed circuit board (PCB). The suite encloses schematic software, a PCB layout software, a Spice software for analogue and digital circuit simulation and other software tools that can help in the development of an electronic device.

EAGLE CadSoft: EAGLE (Easily Applicable Graphical Layout Editor) is a schematic capture and  PCB  layout  tool;  it  contains  a  schematic  editor,  for  designing  circuit  diagrams.  Even though Eagle is commercial software, CadSoft offers also a freeware limited license. One of the  features  relevant  for  fast  prototyping  is  the  presence  of  different  plug-in  that  can  be used, with Eagle, for example to create 3D Model of the electronic circuit which can be used during the definition of package and model.

ARDUINO: Arduino is an open-source electronics prototyping platform based on flexible hardware and  software  specially  developed  for  artists,  designers,  hobbyists  and  anyone interested  in  creating  rapidly  interactive  projects  (Thompson  2008).  Arduino  is  a  piece  of open source hardware, free for anyone to use, modify, or sell so that can be also used in real commercial  project.  The  “power”  of  Arduino  is  the  online  community  created  in  the  last years  around  this  open  source  hardware.  Today  we  can  find  a  huge  variety  of  different project  with schematic  or  already  mounted  electronic circuits  which can be  easily  used  to create  prototype  with  different  characteristics.  Nevertheless  we  can  also  find  numerous libraries to program the ATMega microcontroller mounted on Arduino; in this way the time needed to design the firmware controlling all the hardware parts is considerably reduced.

Opensource for software/firmware design

A software platform for biomedical data display and processing (BCI++): BCI++ is a free and  open-source  (GPL)  framework  dedicated  to  biomedical  data  display  and  processing, and easy creation of User Interfaces. Originally it was designed with specific application to the  development  and  fast  prototyping  of  Brain  Computer  Interface  (Wolpaw  et  al.  2002) systems, PC-driven protocols for different bio-signal acquisition paradigms and BCI- based applications (Perego et al. 2009). BCI++ framework is composed of two main modules that communicate  via  TCP/IP  connection.  The  first  module,  the  Hardware  Interface  Module (HIM) is dedicated to signal acquisition, storage and visualization, real-time execution and management of algorithms (developed both in C++ and Matlab®). The second module is the Graphics User Interface (AEnima); this module is dedicated to create and manage pc-driven protocols based on a high level 2D/3D Graphic Engine. This structure is thought in order to split the development of a system into two parts: the part regarding signal and algorithms (the Back-End) from the graphic interface (the Front-End).

The  HIM  module  allows  interfacing  the  product  with  many  commercial  medical  devices (Perego  et  al.  2009)  and,  with  the  use  of  express  Visual  Studio®  wizard  presents  in  the framework,  to  easily  connect  new  devices.  This  module  allows  also  to  test  Real-Time algorithms for bio-signal processing developed in Matlab®, and rapidly convert into C/C++ language with C4M library which can be found in the framework.The Aenima module is based on a open source high performance real-time 3D C++ graphics engine (Irrlicht) and an open source audio engine (IrrKlang) which allow the easy and rapid creation  of  immersive  environment  with  an  high  level  of  multimedia  contents.  Figure  4 shows an example of high multimedia contents graphics interface for a videogame used for disabled  people  software  testing.  The  Aenima  module  is  particularly  useful  and  used  for User Interfaces development.

Front-end layer concept design

The Front-End layer consists in all the parts that will be in contact with the user and with which the user will interact, both physically and cognitively (interfaces, commands, buttons, icons, …).In  most  cases  the  role  of  the designer  in  a  project  is  to  humanize  the  interaction  between user and technological device, to engender trust, to offer control and to minimize risk from clinician and patient perspective. Design for intuitive interfaces is the leading philosophy. As for the technological point of view, also user interaction needs to be early tested. In this process,  users  are  involved  to  evaluate  the  first  three  steps  of  the  hierarchy  of  users constrains:    anthropometrics,    physiology    and    psychology    (Moggridge,    2006).   Users involvement is again obtained through tests with models or prototypes. Users’  interactions  could  be  expected  or  real.  At  the  beginning,  designers  could  imagine how users will interact with the product and represent this interaction in a storyboard and then, with a real session of test, modify the interaction paradigms refining the user needs.

Early user test

As said before only the methodologies of “Oz Wizard” or Fast Prototyping (with some real functions working) could support this step to obtain significant information about concept assessment. Usually paperboard prototypes, foam or wood mock-ups are used to evaluate anthropometrics interaction in order to define general characteristics and dimensions of the packaging.  Evaluating  physiological  aspect,  as  range  of  movement,  the  importance  of  the product  weight  and  the  accessibility  of  commands  is  also  possible.  Storyboards  or  movie scenarios  (video  prototyping)  could  be  used  to  present  a  complex  situation  in  order  to immerse  the  user  in  a  virtual  context  before  evaluate  the  interaction  with  models.  These kinds of tools are particularly used in service design.

Advanced (late) user test

In a second stage, front end prototype is developed with more sophisticated methods: 3D Models could be done using open-source software like Blender and physical prototypes can be  built  with  ABS  printer  or  stereo-lithography  as  previously  reported;  Graphical  User Interfaces   (GUI)   can   be   simulated   using   FlashDevelop,   PROCESSING,   or   the   BCI++ platform  already  presented.  Normally  a  quite  final  product  can  be  necessary  in  order  to evaluate also the physical/mechanicals issues of the product in a normal condition of use. Those  prototypes  can  already  contain  electronic  circuits  and  boards  and  the  test  are performed  directly  in-field  (Erdmann  at  al.  1971).  Also  the  user  interfaces  is  almost complete:  LEDs,  buttons  and  connectors  are  built and  present  at  this  level  of  realization, while  colours and  icons  could  be integrated  in a very  short  time  even if  not  in  their  final configuration.  Thus,  in  this  advanced  stage  thank  to  the  availability  of  a  well  detailed prototype  it  is  easier  to  evaluate  also  cognitive  and  psychological  aspects  of  the  user- product interaction.

PROCESSING:   Processing   is   an   open   source   programming   language   and   integrated development environment (IDE) for people who want to easily create user interfaces. One of the main features of Processing is the presence of a huge online community where to find a great number of libraries or already tested small software that can be rapidly included into programs. Processing  was  initially  developed  from  the  idea  that  “programming  is  not  only  for engineers” for  this reason the creation of software is very  simple, nevertheless processing permits to use and interact with images, videos, sound and so on. Another  fundamental  aspect  of  this  programming  language  is  the  fact  that  it  is  cross- platform. Processing is based on Java™  programming language, the entire IDE software run on Java™  Virtual Machine and allow to the users/programmers to create and export their software  in  different  packages  so  that  can  be  used  under  Windows©   Os,  Linux  Os  and Mac©  Os. A Spin-Off for prototyping software in mobile phones exists (Mobile Processing) and allows designer to create small software for smart-phone and cellular phone supporting JavaME.

Risks in fast prototyping

Rapid prototyping is basically an analysis technique through which the designer can rapidly discover  the  true  and  complete  set  of  formal  and  functional  requirements  for  a  proposed product.  In  classical  product  development,  the  user  usually  cannot  view  rough  physical representation of the final product until the testing phase; this is critical in projects with very long  development  times  results  in  a  very  low  probability  of  producing  an  acceptable product.  Nonetheless  „all  that  glitters  ain’t  gold!“;  the  wrong  use  of  Fast  Prototyping  can bring to worse result than classical development, there are in fact some risks the user can fall:

•    Mistake  concepts  of  rapid  prototyping  concerning  definitions,  objectives  and  correct application of technique;

•    Disagreements with users and costumers regards methodology, standards, tools and so on;

•    Out of order test user who want to interact and evolve a prototype into a system that does everything for everyone all of the time;

•      Budgets slashes and efforts shortcuts dictated by the word „fast“;

•     Premature delivery of a prototype indeed of final;

•     Over fitted prototype substituting elegance and efficiency for flexibility.


As  discussed,  using  fast  prototyping  techniques  from  the  early  steps  of  product  design process  is  fundamental,  especially  in  healthcare  field,  where  usability  can  strongly  affect safety  during  clinical  processes  (diagnosis,  monitoring,  etc.)  and errors  in  these  issues are not acceptable by definition.In  the  previous  paragraphs  we  presented  and  discussed  different  steps  in  a  process  for product design in the healthcare environment. For each of those steps we showed also some examples of new prototyping technologies and tools. We  explained  how  the  introduction  of  tools  for  anticipating  user  involvement  and  tests (Figure  9) could  produce  a  significant  improvement  in  both  time-to-market,  and  user satisfaction together with costs and resources savings

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