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Wednesday, May 18, 2011

Other Specialty Matrices Used in QFD

7.5 Other Specialty Matrices
As previously stated, there are several approaches to QFD; each of these approaches makes use of matrices to organize and relate pieces of data to each other. There are typically four basic QFD matrices for Product Development.  The basic structure of these matrices relates WHAT’s to HOW’s for each of the four product development stages.  Since one of the objectives for System Engineering is to understand and determine relationships at all stages, there are other WHAT vs. HOW relationships that are important. Two “Specialty Matrices” that are important in front end system development are: 1) Preplanning Matrix and 2) Functional Architecture of the system (the WHAT’s) versus the structure of the Product Design, (the HOW’s)

7.5.1 Pre-Planning Matrix (PPM) - A Pre-Planning Matrix (PPM) is sometimes used in the product planning phase prior to launching Product Development.  The PPM provides an assessment of current company capabilities versus the expected competition. The assessment is taken from where you believe the Customer rates your capabilities and your competition.  The assessment identifies current strengths and weakness and shows where investment is needed to create a better competitive position prior to entering into the pursuit and/or development of a product.  It also provides a method of identifying potential teaming, strategic partnerships and/or alliances to strengthen product development and improve competitive position. The PPM provides a means for prioritizing investments that might be needed to become competitive and increase the probability of win or sale.
The PPM also identifies potential Sales Points.  A Sale Point is where current capabilities or the combined capabilities of a team provide a leading competitive position.  The Sales Point is used to communicate with customer(s) and to emphasize why a team or product is superior to its competitors.
The PPM consists of the following sections; 1) Voice of Customer (VOC) requirements, 2) An order of importance of VOC, 3) Competitive Assessment, 4) Identification of probable Sales Points, 5) Improvement Factor of VOC, 6) A new weighted VOC,
Figure 7-18 illustrates a partial sample of a PPM.  In reviewing the matrix Section A in Figure 7-18 lists each VOC requirements followed by a column that rates importance level of VOC on a scale of 1 to 5, with 1 rating being least important and a 5 rating being most important.  Section B in Figure 7-18 provides an assessment of the competition and your current capability through the eyes of your customer for your company and each competitor, followed by an identification of probable Sales Points.


Figure 7-18 The initial PPM is constructed to show current competitive position and identify Sales Points.

The PPM as constructed so far shows that our present competitive assessment indicates that Company B has a better competitive position.  The PPM also indicates that Our Company presently has two Sales Points to emphasize; that our product is Easier to Use and Easier to Hold versus competitor Company A and Company B.
Since the PPM from Figure 7-18 indicates that Company B has a better expected competitive position than Our Company for the defined VOC and Importance Rating, something must be done by Our Company to better the competitive position.  Figure 7-19 illustrates a further expansion of the PPM to include additional sections.  Section C includes Our Company Plan to increase capability in the “eyes of the Customer”.  The column marked Our Target Position the improvements needed to increase the probability of convincing the Customer that Our Company has a better capability and therefore provides a more favorable chance of winning the Customer’s approval.  However to achieve that Target Position Our Company needs to improve in two areas of the Customer’s view of our capabilities; 1) Waterproof and 2) Light Weight.  Light Weight has an Importance Rating of 5 and it requires an improvement of 9:1 from our current position, Our Company gives this a top priority action, (Priority #1).  The final column provides for a summary of Our Company’s Strategy to go forward to capture the customer’s approval.  Accomplishing this development and partnering effort should provide Our Company with a strong competitive position over Company B, (i.e. a Relative Importance Rating of 162 versus Company B’s 101 rating).

Figure 7-19 Adding Section C to the PPM provides a prioritized strategy to improved competitive position.

The PPM as presented assumes that Company A and Company B do nothing to improve their competitive position, but in reality that is not likely to be the case.  A further extension of the PPM is to forecast where Our Company thinks Company A and Company B might make improvements.  For example if Company A and Company B were to establish a Strategic Alliance and combine their capabilities then the best of each company capability would result in a Relative Importance Rating of 125, which is still lower than our anticipated improved rating of 162.  This assumes that Our Company is able to implement the identified strategy and investments and convenience the Customer of its improved capabilities.
There are other methods for the development of the PPM instead of the non-linear ratings used in Figure 7-19.  For example instead of the non-linear symbols a numerical rating of 1 to 5 can be used to assess Our Company and Company A and B’s capability.  However the overall benefit of the PPM is the process of walking through the questions and assessment needed to establish a company’s competitive position and provide priority and direction for further investment in development and/or teaming with another company.
It must be noted that other than identifying and emphasizing current Sales Points, nothing is attributed to the Relative Importance Rating for having these Sales Points over the competition.  Some PPM methods assign a value of 1.5 for each Sales Point and multiply the VOC item by 1.5.  If that had been done in this example the first Relative Importance Rating for Our Company would be 114.5 versus Company A’s 77 and Company B’s 101.  This approach would influence whether Our Company might alter its strategy on investment or teaming.  The decision would depend on Our Company’s ability to convince the Customer that these Sales Points provide increased value.  It is easy to error based on self-evaluation and could lead Our Company into a false sense of competitive position.

7.5.2 Function vs. Product Design - One of the basic building blocks of QFD is the identification of the functions that a product or service must provide.  Every product or service has a basic all-encompassing purpose.  The primary or basic function is identified as the prime reason for the product’s or service’s existence. Functional Analysis/Allocation (FA/A) is an early step in the system engineering process, that defines a baseline of functions and sub functions and an allocation of decomposed performance requirements. The FA/A task is to create a functional architecture that provides the foundation for defining the system physical architecture through the allocation of function and sub function to hardware-software and/or operations (i.e. personnel).
It should be clearly understood that the term “functional architecture” only describes the hierarchy of decomposed functions and their allocations of performance requirements to functions within the system. It does not describe either the hardware architecture or the software architecture of the system. It describes “what” the system will do, not how it will do it. Therefore once the functional architecture of the system is defined and a conceptual baseline approach is generated the correlation of functional architecture to physical (hardware & software) architecture needs to be generated to determine:
·         Where the function and sub functions are going to be performed in the physical design of the system and
·         If all of the functions and sub functions are being performed
·         The interfaces and what must cross each interface to perform the intended functions.
Figure 7-20 illustrates an example of a QFD matrix that correlates Functional Architecture with one potential Physical Architecture of the system. This QFD matrix provides a graphical picture of the coupling of Functional Architecture (What is to be accomplished) and Physical Architecture (How and where function is accomplished) along with were interfaces are required. Customers would likely define the primary function or all-encompassing purpose of a camera as “Take a Picture”. The systems engineer decomposes this primary function into the needed functions of Capture an image of a scene, Store the image, Display the image and Readout the image. The example illustrated in Figure 7-20 relates the needed function Capture an Image of a scene and the relationship of this function and its sub functions to a potential hardware concept.
In principle functions and sub functions can be defined totally independent of the technologies used in implementing the functions. However, often a decision is made on one or more of the technologies to be used as the result of market analysis or constructing a PPM.  To complete this decision may require Technology Trade Studies to select the best technology approach. Let’s assume a choice between a photographic process using a light sensitive material and a digital technique using a charge coupled sensor where the image is electronically captured and stored on a focal plane of electronic detectors.  Assume the decision after making a trade study of the advantages and disadvantages of both technologies is to capture the image electronically using an electronic device known as Charge Coupled Device (CCD).  The sub functions that are associated with an electronic method of image capture include:
·         Convert image light to electrical signal
·         Focus light
·         Control light intensity (to match CCD detector sensitivity)
·         Condition light
·         Block unwanted light
·         Position light
·         Support & protect components
A simplified baseline concept is to implement an electronic sensing material called a Charge Coupled Device (CCD).  The subsystem components that make up the hardware tree for a camera using an electronic sensing approach are:
·         CCD focal plane and electronic signal processing
·         Entrance focus lens that places the image at the CCD focal plane
·         Mechanical housing that proved structural rigidity and blocks outside light from CCD focal plane
·         Entrance aperture baffled to block stray light
Ideally a function is performed in only one module or subsystem.  This simplifies the interfaces, however this may be impossible to achieve.  In reality functions are likely to be accomplished over more than one subsystem and therefore over one or more interfaces.  Figure 7-20 provides a summary of a Functional to Physical QFD Matrix for this example and illustrates the following information:
·         All but two sub functions are achieved in an individual subsystem
·         Two sub functions, Control Light and Block unwanted light are accomplished in more than one subsystem.  Therefore any performance requirements associated with controlling light and blocking unwanted light are allocated over more than one subsystem
·         The subsystem Entrance focus lens & housing must support more than one function.  In this case it supports five different sub functions. 

When more than one sub function is accomplished in the same physical subsystem there can be potential interaction or interdependence of sub functions.  Also as the number of sub functions increases in any one subsystem complexity also increases. In this example an analysis should be performed to determine if functional performance of the sub functions interacts or is influenced by the other functions in the subsystem.  Tradeoff of performance may be necessary to balance out overall performance. These considerations are not readily apparent without construction of the Functional to Physical QFD Matrix.


Figure 7-20 An example functional to physical matrix for the Capture Image function of a digital camera.
It has been documented in Product Development activities that the Functional Architecture for a product or service varies little from one product version to another.  The Functional Architecture is not an invariant, but will change only slightly from one product version to the next.  The application of different technologies and design changes will cause the hardware/software tree to be different from one product version to the next.  The Functional Architecture can be considered as a “re-engineering point” from one product release to the next.  Therefore the Functional Architecture can be considered as a pattern of functions to be either reused or to be a starting point for new product/service development.



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