Development Process with Regard to Customer
Requirements
Jože Duhovnik, Janez Kušar, Rok Tomaževič, Marko Starbek
To cite this version:
Jože Duhovnik, Janez Kušar, Rok Tomaževič, Marko Starbek. Development Process with Regard to
Customer Requirements. Concurrent Engineering: Research and Applications, SAGE Publications,
2006, 14 (1), pp.67-82. 10.1177/1063293X06064149. hal-00571190
HAL Id: hal-00571190
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CONCURRENT ENGINEERING: Research and Applications
Development Process with Regard to Customer Requirements
Jože Duhovnik,1,* Janez Kušar,1 Rok Tomaževič2 and Marko Starbek1
1
University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, SI-1000 Ljubljana, Slovenia
2
CIMOS d.d., Marežganskega upora 2, SI-6000 Koper, Slovenia
Abstract: Today, it can be maintained that the customer is a ‘king’ as he will buy only the products that satisfy his needs and wants. The
companies of today are facing new challenges: global business and local operation, standardization, and individualization of products,
demanding customers and fierce competition. The company wants to achieve shorter product development time, lower costs, high quality of the
product, and finally, customer satisfaction. In order to achieve the set goals, the company has to take into account the customers wants and
needs during the new-product-development process. This article presents the mode of description of processes that allow recognition of
suitable natural systems and their transformation into technical systems and a model for management of development process. The phases of
quality functions deployment (QFD) during the new product development process along with the location for collecting customer needs and
wants are presented. A detailed description is given on information resources for obtaining data on customer needs; the methods for obtaining,
structuring, and evaluation of the data obtained. The results of testing the proposed methodology of taking into account the voice of the
customer in the process of developing a new Vario Flow product in a company that produces and sells medical equipment in domestic and
foreign markets are also included.
Key Words: nature processes, technical processes, golden loop of continuous improvements, customer needs, decision-making process,
house of quality.
1. Introduction
2. Customer’s Part in Development Process
Product development activities are well known and
recommended with various scientifically verified methods. The main difference between them is in understanding of the process itself. Designers understand
development and design activities as a complex process
which encompasses other fields as well, and they search
for the best solution [1–4]. The researchers of product
development try to define the new product development
process as a new scientific field which should define
development processes (by using scientific methods)
from man’s abstract idea to the actual product [2].
Product development and design within a global
product realization concept allow a variety of services
that enables a customer to use the product in different
environments. This is the main demand in every product
development and design process.
In continuation, a model of new product development
and design, as well as the methods for obtaining and
evaluating the information on wants and needs of the
potential customers are presented.
Natural processes act in an environment consisting of
interlinked and properly functioning natural systems
(Figure 1). Man recognizes natural processes and
searches for more or less ideal substitutes. Recognition
and description of natural processes is carried out in
various forms, either formalized or non-formalized.
Description is based on the ontology of phenomena,
described by natural or technical sciences. The modes of
description of processes that allow recognition of
suitable natural systems and their transformation
into technical systems are carried out using specific
knowledge, based on the ontology of the system
transformations. The success of transformations can
be estimated by several methods. Improvement of
technical systems is based on teleological methods
(target-oriented methods are defined according to a
particular system or process under consideration).
Because of this it is possible to say that the product
requirements are being fulfilled either more or less,
and it is possible to talk about the perfection of the
product. The evaluation is general and does not consist
of technical evaluation only [5].
While evaluating the products, certain starting points
are used, based on attributes. Because the attributes
are defined anew in each product (depending on the
defined technical system), it can be expected that in
product development activities it is essential that a goal
*Author to whom correspondence should be addressed.
E-mail: joze.duhovnik@lecad.uni-li.si
Figure 4 appears in color online: http://cer.sagepub.com
Volume 14 Number 1 March 2006
1063-293X/06/01 0067–15 $10.00/0
DOI: 10.1177/1063293X06064149
ß 2006 SAGE Publications
67
68
J. DUHOVNIK
ET AL.
UNIVERSE, EARTH,
ENVIRONMENTAL
NATURE
Nature processes
PRODUCT
OF THE MAN
Technical processes
Recognition,
Description
ONTOLOGY
Natural and technical
science
NATURE
Nature systems
Recognition
Description
Substitution
Comparision & definition
Goal definition
PRODUCT
OF THE MAN
Technical systems
Description,
Substitution,
Comparision
Figure 1. Nature and technical processes.
IDEA, TASK, IMAGE, REQUEST
CUSTOMER NEEDS AND
WANTS RECOGNITION
PROBLEM DEFINITION
FIRST
LOOP
DESIGN GOAL
TASKS, REQUESTS, NEEDS
DEFINITION OF DESIGN PROCESS
DESIGN LEVEL
DESIGN TEAM
DESIGN WORK PLAN
Figure 2. Customers voice in product development process.
should be defined properly (i.e., as clearly as possible).
It has to be emphasized that the definition of a goal
is the starting point that allows the qualitative product
development process [6].
In this study the authors would like to identify the
goal as clearly as possible, so as to define the essential
environmental influences, in this case, those from
nature. Before defining the goal the authors would like
to present the general model of the product development
process (Figure 2).
Product development and design process is carried out
in numerous loops that follow one another in a logical
sequence. Recognition of customer requirements is the
most sensible and important process phase. It is understandable that here an attempt has been made to
establish the product development goal from customer
needs as soon as possible. Therefore the problem
of direct transformation of customer needs into the
goal itself appears. As a rule it is not possible, as
the customer and product development team are not
Development Process with Regard to Customer Requirements
69
Correlation
of HOWs
INPUT
Voice of the
customer
WHAT
do customers
wish (voice of
the customer)
Level of WHATs'
support to HOWs
TECHNIQUE
HOW
can the company
fulfil the
customer needs
WHY
improve
OUTPUT
(comparision
with competition) Important and
critical HOWs
MARKET
HOW MUCH
does the company
wish to achive with
HOWs
Figure 3. Product’s quality-functions-deployment house.
the same. They have different knowledge and comprehension of the product and product development
possibilities. Product development team has to identify
the problem from the customer requirements and define
the goal. The process is iterative (closed in a loop) as
shown in Figure 2.
3. The Concept of Obtaining the Customer
Needs and Wants
A new product development process starts with an
abstract idea and ends with physical realization of the
product (Figure 2). Experience has proven that in this
mental and physical product development process the
voice of the customers has to be taken into account in
order to ensure that a globally competitive product is
produced.
Quality functions deployment – QFD [7–10] is the
only customer-oriented product-development method,
where the ‘voice of the customer’ is the starting point
of all activities.
The QFD starts with the question: ‘What does the
customer need and want?’ and transforms the customer’s expectations into the product features. The goal of
the QFD method is to define, develop, design, manufacture, supply, and install the product in such a way
that customer wishes are overfulfilled rather than only
fulfilled.
The QFD method is a game of questions and answers
with two basic questions:
. What do customers expect from the product?
. How can the company fulfill the customer needs?
The QFD method is used throughout the product
development process: from the first abstract concept to
the use of the product. ‘Product’s quality-functionsdeployment house’ (Figure 3) is used for recording
mental and planned results.
Practical cases of QFD method introduction [10] have
shown that finding customer’s real requirements
(INPUT – voice of the customer) is a necessity for
forming a real product’s quality-functions-deployment
house. Therefore, further research was aimed at designing a concept for obtaining the data on customer needs
and wants (Figure 4).
In order to take into account the customer needs
during new product development, they must be identified and analyzed beforehand, so that they can be
properly understood and fulfilled.
3.1
Sources of Customers’ Voice
Voice of the customers is a concept that describes
the uttered and unuttered customers’ wants and
needs; as such it must exist in order to start the new
product development process. A customer need is
a description, in the customer’s own words, of the
benefit to be fulfilled by the product. Customers often
express their needs using statements that describe
how these needs could be fulfilled and these statements
are called ‘customer requirements’, which are considered
as something required, something that is non-negotiable.
70
J. DUHOVNIK
MARKET ANALYSIS
»VOICE OF THE CUSTOMERS«
ET AL.
voice of customers sources
obtaining of customers' needs data
structuring of customers' needs data
Methods for data evaluation
CUSTOMERS' NEEDS VECTOR
evaluation of customers' needs data
input data for the product plannig house
Figure 4. The concept of obtaining, structuring and evaluation of customer needs and wants.
The voice of the customer research scope depends on
the product type, conditions and the size of the market,
the number of products, funding, and the available
human resources.
There are three major sources for obtaining the
information on the voice of the customer [11,12]:
. external customers, internal customers, and information on products and processes.
External customers (product users, people influencing
other people in the process of purchasing, and people
making the final financial decisions) fall into several
categories and sub-categories, depending on the
vendors they buy the products from (buying one’s
products, buying the competitive products) and on
their role in the supply chain (regular customers of
competition, former customers, dissatisfied customers,
satisfied customers).
Internal customers (company engineers, product
designers, project managers, and suppliers) are customers who are from the company and most certainly
use a different language than the external customers.
Internal customers have a unique perspective on specific
problems in the product and process development,
and that is why their voice must be distinguished from
the voice of external customers. The voice of internal
customers can significantly contribute to the product
and process development, as it is very important for
them to improve the product development they are
a part of. In this way they contribute to satisfying the
needs of external customers.
Information on products and processes (data on
errors, repairs and maintenance, customer complaints
and observations, vendors product and competitive
product specifications, warranty data, price-lists) is
significantly helpful in discovering the needs of the
customers, both the internal and external ones.
During product development it is necessary to
initially define the level of product development, i.e.,
‘Will a completely new product be developed or will only
an adaptation be made?’
A new product represents a complete novelty in
the environment of new customers; it requires a new
production environment, and usually generates new
enterprises, profit centers or workshops. Adaptation of
the product mostly requires total adaptation to the
customer in all details; production process has to be
adapted to the customer wants, too.
Customer needs and wants are therefore important
in recognition of the level of product development.
3.2 Obtaining the Customer Needs
and Wants Data
Various methods for obtaining the data on customer
needs and wants were analyzed and evaluated [11–14];
the result of those analyses is a proposal of the most
suitable practice for obtaining the data on customer
needs and wants:
. Brainstorming, focus group method, interview,
customer remarks and complaints method.
Development Process with Regard to Customer Requirements
The brainstorming method is the most popular
and the most widely used creative method for
obtaining the data on customer needs. When using
this method, four basic rules should be taken into
account:
Rule 1: Any criticism or evaluation of ideas is strictly
forbidden because it obstructs creative thinking.
Rule 2: Ideas of other team members can be used and
developed further.
Rule 3: Team members should activate their imagination
as much as possible during problem solving.
Rule 4: As many ideas as possible should be proposed
in the shortest possible time.
The focus group method uses a selected group of
customers who are discussing questions posed by the
moderator. The discussion is initiated so that each group
member first expresses his/her opinion on a particular
problem, then other participants comment on it and
then further discussion of their opinions follows. In
this way the discussion of the focus group provides
a qualitative view of a small number of people. The
moderator can search for reasons causing dissatisfaction
and can discuss possible solutions for particular
problems. Normally, there are 6–12 people in a
discussion group, each discussion lasting for 2–3 h.
To be able to provide a productive discussion on
a particular subject, discussion members with similar
interests and knowledge must be selected. Experience
shows that care must be taken that the members are
neither in superior nor in subordinate relationship to
each other.
Normally, there are several focus groups formed in
the research project (external and internal customers
are grouped by different segments) with the goal of
gathering different opinions on a problem.
The focus group work is directed by a moderator
who starts with an introduction by presenting the focus
group, its purpose and the reason why the members
have been invited. Then the members are acquainted
with the basic rules and explained the purpose of having
the discussion recorded and discretion of the participating members ensured.
Then the members participating in the discussion
are introduced and the moderator starts the discussion
by asking the initial questions in order to gather
different views regarding the topic of the discussion.
The moderator’s basic task is to keep the discussion
group focused. After a question has been generally
discussed, the moderator can search further to get more
information by using additional teaser questions.
Normally, it is required for the moderator to be an
expert in the field discussed by the group and to be
acquainted with the subject of the study. It is his or her
goal to help the group to create a productive discussion
71
on the specified topic. The quality of data in the focus
group mostly depends on how efficiently the moderator
is asking questions and focusing the entire group on
the topic. The moderator must work as a promoter,
controlling the interaction between himself/herself and
the members as well as between the members themselves.
Some members of the focus group are usually more
eloquent while others are more reserved, so the
moderator has to find a way to silence the too eloquent
people in order to make the quiet ones to start speaking
as well. When all the issues have been discussed, the
moderator concludes the work of the focus group.
The focus group discussion is normally carried out
in a special room. The room can have a special one-way
see-through wall, behind which there can be video
and audio recording equipments, as well as additional
observers.
The interview is a method of gathering qualitative
information through a dialog between the interviewer
and the interviewee. It enables them to gather detailed
information on the customer needs and identify
innovative solutions. The quality of the interview is
measured by the number of recorded needs.
Depending on the area and size of the project, the
following must be selected: the customers to be
interviewed, the locations where the interviews are
to be carried out, the interviewers, and the type of
questions asked.
The most common form of an interview for obtaining
the customer needs is a conference room interview.
During the conference room interview it is necessary
to rely upon the ability of the interviewees that they
recall the things they liked or disliked in the product,
and that they try to mention the things they missed.
The interviewer has to have some sort of an interview
guide that serves as a checklist of the subjects to be
asked about during the interview.
The conference room interviews enable good timeplanning and efficient use of time.
Figure 5 shows the course of obtaining the customer
needs and wants data with the focus group method and
the conference room interview method.
Contextual inquiry is carried out on the location
where the product is being used. It allows the interview
to be conducted during observation of the actual use
of the product.
Contextual inquiry is used mostly for better understanding of the environment (weather, culture, values)
where the customer uses the product. Contextual inquiry
is a partnership between the customer and inquirer
during their search for solution of the identified
customer needs.
Customer requirements, obtained from the customer
remark and complaint database are qualitative data,
which cannot be generalized to a wider population
because of the way they were obtained. It often happens
72
J. DUHOVNIK
ET AL.
Moderator / Interviewer
Focus group members / Interviewed customer
Start of the focus group work / conference room interview
Moderator/interviewer sets an open question to the members of
the focus group/interviewed customer (on a specific topic).
The customer(s) answer the moderator's/interviewer's question, focus group
members react to one another, customer(s) express their/his needs, wants,
technical solutions, value characteristics, goals, reference values and other things.
Is this an
actual need?
Yes
No
No
Recording other statements of the customers:
- technical solutions,
- technical characteristis,
- value caracteristics,
- goals,
- reference values,
- other things.
Storing actual
needs
Have all the
customer statements
on a specific topic been
reviewed?
No
Have enough actual
needs on a specific topic
been determined?
No
Yes
Have all
the topics been
discussed?
Yes
Further questions from the moderator/
interviewer aimed to discover any hidden
needs, included in the written statements
of the customers:
- Why do you want that?
- What benefit do you expect from that?
- You want this in order to be able to...?
Yes
End of the focus group work/ conference room interview
C
Audio recording
Camera
Observers
Figure 5. Obtaining the customer needs data – focus group/interiew.
that certain people complain out of a habit, or others
who have had an especially bad experience, and
particularly those who have time to complain.
Customer complaints reveal the causes of dissatisfaction. The needs obtained from customer complaints can
be used in addition to the customer needs obtained by
interviews and focus groups.
The procedure of obtaining the customer needs from
customer complaints consists of the following steps:
Step 1: random retrieval of a certain number of
complaints from the database,
Step 2: translation of complaints into positive expressions and concepts, which represent hidden needs of the
customers, expressed by the complaint,
Step 3: removal of duplicates,
Step 4: marking of each expression obtained from
customer complaints, and
Step 5: combining customer complaints with the
expressions obtained by other methods.
3.3 Structuring the Data on Customer Needs
Structuring of the data on customer needs and wants
is carried out in the following sequence:
Step 1: Design of initial tables for the voices of the
customers
Step 2: Design of the tree diagram.
Development Process with Regard to Customer Requirements
3.3.1
STEP 1: DESIGN OF INITIAL TABLES FOR
THE VOICES OF THE CUSTOMERS
Using
data
acquisition
methods
various
statements of the customers are obtained, related to
their problems, opportunities, ideas, solutions, wishes,
and needs.
Separation of real customer needs from other expressions is a precondition for structuring the needs and
evaluation of relative relevance of needs that are taken
into account when planning the product. Those who
analyze the quantitative data use the initial tables of the
voice of the customers, which are filled out with literal
customer statements. Table 1 presents the contents of
initial voice-of-the-customer tables.
The ‘ID’ column identifies the source of the customer
statement, e.g., interview number, page number, number
of the line or the date of the interview. It is used for
back-referencing the statements in case further information is required about the source.
The ‘Customer demographics’ column contains the
age, income, occupation, and location of the customer.
The ‘Use’ section describes the context of use of the
product in detail.
The ‘Analyzed statement’ marks whether the statement is a real customer need and/or a possible technical
solution or goal.
(or from left to right). In the tree diagram the primary,
secondary, and tertiary customer needs are shown.
Tertiary needs represent the entrance into the house of
quality of the planned product. Figure 6 presents the
principle of building the tree diagram for the value of
the quality.
3.4
Evaluation of the Data on Customer Needs
On the basis of the data on customer needs, stored in
the tree diagram, it is necessary to evaluate the needs,
therefore, to define the relevance of each customer need.
The analysis and appraisal of the available methods
for evaluation of the data on customer needs [12,15]
has revealed that in order to evaluate the data on
customer needs the most suitable tool is a survey
(conducted either by phone or mail).
The sample for the survey should be selected
randomly, so that each person in the population has
a measurable probability of being selected and thus
the survey results can be reliably extended to a larger
population. The survey can be conducted in the state,
region or municipality.
Phone surveys are expensive and the usual source for
sampling are the phone directories.
Mail surveys cost less; they are very effective when
they are targeted to the users of a particular group
of products and they provide measurable data that
can be generalized to the whole population. The
3.3.2 STEP 2: DESIGN OF THE TREE DIAGRAM
In the tree diagram the needs are structured in
a hierarchical way. It is built from top to bottom
Table 1. Initial tables for the voice of the customers.
Table of products and processes data
ID
Customer
Customer
No. E/I demographics statement
Usage
Who
What
When Where
Why
How
Analyzed
Need/
Type of need/
statement characteristic characteristic
Table for the voice of the internal customers
ID
Customer
No. demographics
Customer
statement
Usage
Who
What
When Where
Why
How
Analyzed
Need/
Type of need/
statement characteristic characteristic
Table for the voice of the external customers
ID
Customer
No. demographics
Customer
statement
Usage
Who
What
When Where
73
Why
How
Analyzed
Need/
Type of need/
statement characteristic characteristic
74
J. DUHOVNIK
PRIMARY
NEEDS
ET AL.
SECONDARY
NEEDS
TERTIARY
NEEDS
- userfriendly
- accessibility
ERGONOMICS
- simple usage
- transportability
FUNCTIONALITY
QUALITY OF THE
PRODUCT
- contemporarydesign
- in harmony with surroundings
DESIGN
- lasting and flawless operation
- user's safety
SAFETY and
RELIABILITY
course of building
Figure 6. Principle of building the tree diagram for the value of the quality.
letter accompanying the mail survey should explain
the reasons for the survey and give assurance of
confidentiality.
To ensure a high response rate, the following rules
should be followed when conducting mail surveys:
With described methods obtained, structured and
evaluated customer needs represent the input data for
the first QFD house of new product development [7,10].
Rule no. 1: Multiple contacts should be used, including:
A company that produces medical equipment wishes
to improve its competitiveness on the domestic market
and to offer its products to the global market.
The company management has decided that it will
establish the customer needs and wants for Vario Flow
product (Figure 7 – it is used in medicine as an aid in
hysteroscopic, arthroscopic, and laparoscopic surgery),
and later on, using the Qualica QFD software [16],
consider these needs in the development of a new version
of the product.
Previous to the procedure of obtaining, structuring,
and evaluating the needs of Vario Flow customers the
company had to ensure:
. sending an announcement of the survey by mail,
. sending the survey with a cover letter to all
interviewees at the same time,
. sending a reminder with contact details, enabling the
interviewees to request a substitute survey,
. sending the last substitute survey with registered mail,
. sending a letter or certificate as a symbol of
appreciation for the cooperation.
Rule no. 2: Use printed paper and memos with
letterheads and contact person details.
Rule no. 3: Use stamped envelopes with printed return
addresses.
Rule no. 4: Enclose a symbolic gift with the first or
consecutive surveys, for stimulation and as a symbol of
respect.
When conducting a survey, the customers are
requested to evaluate each individual need. There are
several methods available for evaluation of the customer
needs [10,15]. Their characteristics, advantages, and
drawbacks are presented in Table 2.
4. Case Study
(i) Transition from individual to team work: Tasks
and problems were till now solved individually. The
potential team members were now acquainted with
the advantages and weaknesses of team work, with
organization and realization of creativeness methods
(these are the bases of team problem solving), and
with organization and of team members and their
roles in team work.
(ii) Consideration of the voice of all customers:
The analysis of existing situation showed that
Table 2. Methods for evaluation of the data on customer needs.
Description of the method
Advantages of the method
Disadvantages of the method
Combined method of sorting
by relevance and assigning
points to the needs
In this method the customers first sort the needs by
relevance in descending order. Then they assign numbers
from a 100 point scale to the needs, giving the highest
number to the most important need and the smallest
number to the least important need.
This method is difficult to carry out when
more than ten needs have to be
evaluated.
Assigning 100 points among
all customer needs
In this method, 100 points are distributed to the customer
needs on the list.
The method is easily comprehensible to
the customers. They already make
comparative decisions when selecting
the order of needs and can easily
assign values from the 100 point scale
to different needs.
The customers must make comparative
decisions when assigning points and
compare the needs relatively.
Prioritization model 1-2-3
The prioritization model 1-2-3 is a method where customers
first determine the needs they find most important. Then
they select the second most important needs. The
remaining needs are considered as the third most
important.The analysts assign 5 points to the most
important need of the customer, 3 points to the second
most important needs and 1 point to the third most
important needs. The sum of points for each need is the
basis for determining the relative relevance of the needs.
In the couple comparison method, two needs are directly
compared in order to determine the more important one.
The need which was selected in favor of others most of the
times, is ranked the highest, i.e., the most important need.
The needs are sorted in matrix form and the results of
comparisons are entered in the appropriate fields of the
matrix.
Couple comparison method
The method is easy to comprehend and
quick to fill in.
The possibility to acquire relative
relevance of needs.
As the attention required from the
interviewees is very high, a lot of time
is necessary to assign the points to
the needs, especially if there are more
than ten needs.
The method is slow when a large
number of needs have to be dealt
with.
The possibility of inconsistent
judgments. Time-consuming when
a lot of needs have to be evaluated.
Development Process with Regard to Customer Requirements
Evaluation method
75
76
J. DUHOVNIK
ET AL.
. production process planning engineer – knows
production processes,
. production engineer – knows possibilities and limitations of manufacturing in the company.
4.1 Sources of the Customers’ Voice
for Vario Flow Product
Project team has established that the following
sources for the customers’ voice for Vario Flow product
are available:
Figure 7. Vario Flow.
. External customers (physicians who perform
endoscopies, scrub nurses who participate
in surgery, and representatives of the company
management).
. Internal customers (engineers responsible for development of the product, processes, quality; suppliers
of components and materials; maintenance crew
which is responsible for normal operation of the
product).
. Product and process data (data on performed maintenance works, customer remarks, and complaints).
4.2 Obtaining the Data on Customer needs
for Vario Flow Product
only internal customers’ voice was included in
product development without any regard to external
customers or data on previously developed products
and processes.
(iii) Implementation of project management of product
development: Existing individually organized
product development did not assure the goal
orientation and it did not include concurrent
engineering elements. Therefore, the desired scope
often was not attained or it was attained after too
long a period and with too high costs.
In order to obtain the data on customer needs
the project team selected the following forms of
interview:
. conference room interviews and contextual inquiry.
After successful implementation of team work
and project management, the company management
appointed a project team for obtaining, structuring,
and evaluating the needs of Vario Flow customers and
for establishment of the input WHAT vector of the
house of QFD of the product. The project team was
consisting of:
The project team selected the first form of interview
because of easier time management of interviewees;
those were 10 people of various profiles: physicians,
scrub nurses, engineers, maintenance personnel, and
company management representatives. Participants
were given general questions in advance so that they
could prepare properly. By agreement the quality
planning engineer was going to conduct the interviews
and contextual inquiry while he is best acquainted with
product and QFD methodology.
35 customer needs and wants were identified by the
interview:
. Moderator: quality-planning engineer – knows well
the QFD methodology and Vario Flow product,
. Team members:
. development engineer – knows design requirements
of the product,
. physician – uses the product in surgical procedures,
. designer – is responsible for the design of the product,
. managing board member – is responsible for
connecting the project team with the company
management and he knows the customers,
.
.
.
.
.
.
.
.
.
.
Special requirements for laparoscopy, arthroscopy . . .
Stability of the system
Quality control
Low production costs
Low warranty costs
Low operation costs
Requirement for suitable suppliers and cooperators
Good system mobility design
Aesthetical suitability for medical environment
Independence of energy source
Development Process with Regard to Customer Requirements
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
Patient’s safety
Device’s safety
Reliable operation
Durability of the device
Safety of operation
Safety of the product and responsibility for consequences
Improvement of human factor errors
Safety for user and responsibility for consequences
Fast transport
Safe transport
Simple maintenance
Simple and quick assembly/disassembly
Simple manufacturability
JIT – just in time
Flexibility of operating environment
Planning methodology
Automatization
Value system
Improvement of organization/management
Training of employees
Workstation
IT management
Requirements of teams
Integration
Tool for response
Another 14 customer needs and wants were identified
during contextual inquiry with users in the operation
theatre:
they carried out the structuring of data on customer
needs in two steps:
4.3.1
STEP 1: FORMING THE INITIAL TABLES OF
THE VOICE OF THE CUSTOMERS
Initial tables of the voice of the customers of Vario
Flow product (Table 3) were formed especially for
external and internal customers and according to the
data on products and processes.
The table of external customers contains 21 needs,
the table of internal customers contains 26 needs,
and the table on product and process data contains 2
needs. For each need the table contains the following
data: ID number of the need, customer demography,
customer statement, use of the need (who, what, when,
where, why, how), analyzed statement and the type of
need or characteristics.
4.3.2
STEP 2: FORMING THE TREE DIAGRAM
FOR VARIO FLOW PRODUCT
In the tree diagram for the value of quality
the customer needs and wants are arranged
hierarchically (divided into the primary, secondary,
and tertiary needs). The tree diagram for the
value of quality of Vario Flow product is shown in
Figure 8.
4.4
.
.
.
.
.
.
.
.
.
.
.
.
.
.
Good visibility in the surgical field
Operator and/or scrub nurse can set the pressure
System pressure is clearly visible
System deficit is clearly visible
Quick exchange of fluid
Higher display resolution
Interior of the body should be accessible
Continuous set of pressure
Heating of water
Following water change, the previous pressure is
taken into account
Pressure can be pre-set
Control of water amount in the system
Battery status warnings
Critical system state warnings
Altogether there were 49 customer requirements
formed.
4.3 Structuring the Data on Customer
Needs for Vario Flow product
After obtaining the data on customer needs and wants
the moderator convened a sitting of project team where
77
Evaluation of the Data on Customer Needs
and Wants for Vario Flow Product
After the analysis of available data evaluation
methods the project team decided to use the postal
survey. A survey form was composed where the primary,
secondary, and tertiary customer needs were stated
and it was sent for evaluation to 50 randomly selected
potential customers of Vario Flow product.
Up to due date, 38 survey responses were received;
in these, Vario Flow customers stated what, in their
opinion, were the most important, less important, and
least important needs. After that the quality planning
engineer – moderator using the ‘Prioritization model
1-2-3 assigned 5 points to the most important feature of
a particular need, less important needs were assigned
3 points and the least important features were assigned
1 point.
By summing up the points obtained from all 38
surveys the project team finally obtained the results
on absolute and relative relevance of a particular need,
as presented in Table 4.
Customer needs, obtained, structured and evaluated
in Table 4, are the input data for the first house of
product planning – development process of Vario Flow
product (Figure 9).
78
Table 3. Initial tables of the voice of the customers for Vario Flow product.
Table for the voice of the external customers
Use
Customer
ID no. demography
1.
2.
:
21
Customer statement Who
Physicians
Continuous set
of pressure
Physicians,
Control of water
scrub nurses
amount in the
system
:
:
Physicians
Critical system
state warnings
What
When
Surgeon
Good visibility
:
Surgeon
:
Improvement of
patient safety
Where
Why
How
Analyzed statement
Need/
Type of
feature need/feature
During entire Operation For uninterPressure should be
Quality Functionality
surgery
room
rupted work
set continuously
Surgeon and The right amount During entire Operation Safety of
Control device Control of water
Quality
Safety
scrub nurse
of water
surgery
theatre
the patient
amount in the device
:
:
:
During entire Operation Safety of
surgery
theatre
the patient
:
Sound signal
:
:
Quality
:
Safety
Use
Customer
ID no. demography Customer statement
2.
:
26.
Inspection
engineers
Development
engineer
:
Maintenance
personnel
Safety of the patient
Reliable operation
:
Simple and quick
assembly/
disassembly
:
Maintenance
personnel
What
When
Where
Why
Need/
Type of
Analyzed statement feature need/feature
How
Prevention of
During surgery Operation
Safety system
injuries
theatre
Prevention of
During surgery Operation Un-disturbed Design solution
deadlocks
theatre
operation
:
:
:
:
:
Easier access to
Faster
Design solution
damaged parts
production
Ensured safety
of the patient
Design solution
improvement
:
Simple and quick
assembly and
disassembly
Quality
Safety
Quality
Reliability
:
Quality
:
Design for
assembly
Product and process data
Use
Customer
ID no. demography
1.
2.
Customer statement
Who
What
When
Where
Why
How
Analyzed
statement
Maintenance Quick exchange of fluid Scrub nurse
Before and
On the product Uninter-rupted
Manual Simple exchange
service
during surgery
fluid supply
of fluid
Physicians
Too small a display
Physician
Insufficient During surgery
On the product To prevent errors
To ensure higher
resolution
display resolution
Type of
Need/feature need/feature
Quality
Functionality
Quality
Functionality
ET AL.
1.
Who
J. DUHOVNIK
Table for the voice of the internal customers
79
Development Process with Regard to Customer Requirements
PRIMARY
NEEDS
SECONDARY
NEEDS
ERGONOMICS
FUNCTIONALITY
QUALITY OF
VARIO FLOW
PRODUCT
TERTIARY
NEEDS
- Good visibility in the surgical field
- Operator and/or scrub nurse can set the pressure
- System pressure is clearly visible
- System deficit is clearly visible
- Quick exchange of fluid
- Higher display resolution
- Interior of the body should be accessible
- Continuous set of pressure
- Heating of water
- Following water change, the previous pressure is taken into account
- Pressure can be pre-set
- Special requirements for laparoscopy, arthroscopy...
- Stability of the system
- Quality control
COSTS
- Low production costs
- Low warranty costs
- Low operation costs
- Requirement for suitable suppliers and cooperators
DESIGN
- Good system mobility design
- Aesthetical suitability for medical environment
SAFETY and
RELIABILITY
OTHER A BILITIES
- Control of water amount in the system
- Independence of energy source
- Battery status warnings
- Patient's safety
- Critical system state warnings
- Device's safety
- Reliable operation
- Durability of the device
- Safety of operation
- Safety of the product and responsibility for consequences
- Improvement of human factor errors
- Safety for user and responsibility for consequences
- Fast transport
- Safe transport
- Simple maintenance
- Simple and quick assembly/disassembly
- Simple manufacturability
- JIT – just in time
- Flexibility of operating environment
- Planning methodology
- Automatization
- Value system
- Improvement of organization/management
- Training of employees
- Workstation
- IT manag emen t
- Req uirements of te ams
- Integr ation
- Tool for response
Figure 8. Tree diagram for the value of quality of Vario Flow product.
Table 4. Absolute and relative relevance of customer needs for Vario Flow product.
ID no.
Customers’ needs
1.
2.
..
.
49.
Good visibility in the surgical field
Operator
and/or scrub nurse can set the pressure
..
.
Tool for response
Total
Absolute relevance (number of points)
Relative relevance (%)
149
190
..
.
63
5370
2.8
3.5
..
.
1.2
100.0
80
J. DUHOVNIK
External customers
ET AL.
Internal customers
Methods for the acquisition of qualitative data on customer needs
Conference room interview
Contextual inquiry
Data on products
and processes
Table of PRODUCTS and PROCESSES data
Table for the voice of the INTERNAL CUSTOMERS
Table for the voice of the EXTERNAL CUSTOMERS
TREE diagram of customers' needs
Evaluation of data
POSTAL SURVEY,
PRIORITIZATION MODEL 1-2-3
Relevance
WHAT
HOW
1st HOUSE
OF PRODUCT
PLANNING
Figure 9. The input data for the first house of product planning of Vario Flow product.
5. Conclusions
A company cannot produce a competitive product
unless the client (end user) takes part in the development
process.
If the clients take part in the new product
development process early enough, then the client (by
expressing his needs) can influence the concept of
the product and the whole product development
process.
Past researches which analyzed the inclusion of
the voice of the customers in the new product development process were related only to the quality of
the product, i.e., the needs that were expressed
mostly by external customers and which represent the
source data for quality functions deployment (QFD)
process [7,17].
Further research of the influence of the voice of
the customers will be focused on establishing the
needs for improvement of not only the quality but
other features as well, such as simplicity, assemblability,
recyclability, responsibility, costs, etc. which are
expressed mostly by internal customers and which
represent the source data for concurrent functions
deployment [14].
By taking into account the needs for improvement
of the required features and values of the
product, the product will be more competitive on the
market [18].
References
1. Duhovnik, J., Kimura, F. and Sata, T. (1983).
Contribution to Methodic in CAD. Eurographics ’83: In:
Proceedings of the International Conference and Exhibition,
University of Zagreb, Faculty of Electrical Engineering,
Zagreb, Yugoslavia, 31 August – 2. September 1983.
Partisipants ed. Amsterdam; New York; Oxford: NorthHolland, str. pp. 113–132.
2. Horvath, I. (2001). A Contemporary Survey of Scientific
research into Engineering Design, In: Proceeding of ICED
01, Glasgow, Professional Engineering Publishing.
3. Hubka, V. and Eder, W.E. (1988). Theory of technical
Systems, Berlin Heidelberg, New York: Springer Verlag.
Development Process with Regard to Customer Requirements
4. Pahl, G. and Beitz, W. (1993). Konstruktionslehre,
Heidelberg, New York: Springer Verlag.
5. Duhovnik, J. (2005). Problem Definition and Design
Goal. In: Proceedings of the 4th DAAAM International
Conference on Advanced Technologies for Developing
Countries, Slavonski Brod, Croatia: ATDC’05. Slavonski
Brod: Mechanical Engineering Faculty in Slavonski Brod;
Vienna: DAAAM International, str. pp. 27–36.
6. Duhovnik, J. (2003). Techniques and Methods for
Product Developments. IV Wroclawskie Sympozjum,
Wroclaw, 11–12 grudnia 2003. Automatyzacja produkcji:
nauka-wiedza-innowacje, Referaty plenarne i sesyjne.
Tom. 1, (Prace Naukowe Institutu Technologii
Maszyn i Automatyzacji Politechniki Wroclawskiej, 84),
(Konferencje, 41). Wroclaw: Oficyna Wydawnicza
Politechniki Wroclawskiej, str. pp. 93–101.
7. Cohen, L. (1995). Quality Function Deployment – How to
Make QFD Work for You, Addison Wesley Longman, Inc.
8. Prasad, B. (1998). Review of QFD and Related
Deployment Techniques, Journal of Manufacturing
Systems, Society of Manufacturing Engineers (SME),
May/June, Dearborn, MI.
9. Prasad, B. (1996). Concurrent Engineering Fundamentals:
Integrated Product and Process Organization, Vol. I,
New Jersey: Prentice Hall.
10. Starbek, M., Grum, J. and Kušar, J. (2003). QFD as
a Method of Integrated Product Implementation.
Strojarstvo, 45(4/6), 159–171.
11. Mazur, G. (1997). Voice of Customer Analysis: A Modern
System of Front-End QFD Tools, with Case Studies.
Proceedings of AQC. Orlando.
12. Crow, K. (2004). Customer Focus and Product Planning,
DRM
Associates,
http://www.npd-solutions.com/
drm.html.
13. Schlicksupp, H. (1977). Kreative Ideenfindung in der
Unternehmung, Berlin, New York: Watter de Gruyter.
14. Prasad, B. (1997). Concurrent Engineering Fundamentals:
Integrated Product Development, Vol. II, New Jersey:
Prentice Hall.
15. Saaty, T.L. (1994). Fundamentals of Decision Making and
Priority Theory with the Analytic Hierarchy Process.,
Pittsburgh, PA: RWS Publications.
16. Qualica QFD – (2003). Quality Planning System, Qualica
Software GmbH, München.
17. Tomaževič, R., Kušar, J., Starbek, M. and Savnik, L.
(2004). Introduction of Concurrent Function Deployment
Method into CE Organization in SMEs, In: Proceeding
of The 11th ISPE International Conference on Concurrent
Engineering, Beijing, pp. 657–662.
18. Duhovnik, J., Starbek, M., Dwivedi, S.N. and Prasad, B.
(2001). Development of New Products in Small
Companies, Concurrent engineering: Research and
Applications, 9(3), 191–210.
81
Jože Duhovnik
Jože Duhovnik is a Full
Professor of computer-aided
design at the Faculty of
Mechanical
Engineering,
University
of
Ljubljana,
Slovenia. His pedagogic and
research work is oriented
towards design theory, development technic, project management, information flow in
CAD, and geometric modeling. He is the founder and head
of the CAD Laboratory at the Faculty of Mechanical
Engineering since 1983.
He received a BS, a MS and a PhD in mechanical
engineering design in 1972, 1974, and 1980, respectively.
His postdoctoral study took place at the Department
of Precision Machinery Engineering at the University of
Tokyo, Japan. He also has several years of engineering
design experience in industry (COLOR - Medvode,
SAVA - Kranj, SCT - Ljubljana, LITOSTROJ Ljubljana, etc).
VDI, IFToMM, Eurographics, New York Science
Academy and ZSiT (National Society of Mechanical
Engineers).
He is currently professor at the University of
Ljubljana and the University of Sarajevo.
Janez Kušar
Janez Kušar is an Assistant
Professor at the Faculty of
Mechanical Engineering, University of Ljubljana, Slovenia.
He received his PhD degree in
1999 in the field of production
planning and control. His
research fields include: project
management, especially in
individual and small-series
production, material flow optimization, production planning and control systems and
projects of transition from sequential to concurrent
engineering. He is a member of IPMA (International
Project Management Association).
In these fields he published 27 works in scientific
journals and more than 50 papers in conference
proceedings.
82
J. DUHOVNIK
ET AL.
Marko Starbek
Rok Tomaževič
Marko Starbek is a Professor
and chairman of the chair
of Technical Cybernetics,
Manufacturing Systems and
Computer Technology at the
Faculty of Mechanical Engineering, University of Ljubljana,
Slovenia. He received his PhD
degree in 1978 in the field of
production planning and control. In 1993 he was on a oneyear advanced scientific study
in the TU Graz. His research fields include: material
flow optimisation in companies with individual and
small-series production, finding the real flow times of
operations and orders, production planning and control
systems, project management and projects of transition
from sequential to concurrent engineering. He is a
member of DGOR (Deutsche Gesellschaft für
Operations Research).
In these fields he has published more than 25 works in
scientific journals and more than 100 papers in
conference proceedings.
Rok Tomaževič received a
B.S. in Mechanical Engineering
from the University of Mechanical Engineering in Ljubljana in
2003. After graduation he has
been working as an research
assistant at the chair of production systems at the University
of M.E. in Ljubljana. At the
moment he is working as a
Quality designer at Cimos d.d.
(Automotive industry), where
he is continuing his research work as a master candidate.
His current research interests include requirements
engineering, product and process improvement and
control.