Page 484 - Biomedical Engineering and Design Handbook Volume 2, Applications

462 REHABILITATION ENGINEERING AND PROSTHETICS DESIGN

TABLE 16.1 Additional Customer Requirements for a System to Detect Apnea
Captures all events Panic button Easy installation
No false positives Electrical safety Comprehensive instructions
Doesn’t irritate the skin Patient comfort Per patient basis adjustability
Can’t harm the baby Visible vital signs User-friendly interface
Doesn’t impact handling the baby No bigger than a band-aid Plug-and-play capabilities
Washable Will not burn patient Aesthetically pleasing
Easy to take on/off Rechargeable Wireless
Waterproof Reusable construction Portable
Not attached to the baby at all Replaceable battery Labeled connections
Easy to operate Long battery life Reads EKG signal
Disconnect alarm Easily sterilized Reads respiratory rate
Animal/kid proof Disposable parts Reads heart rate
Low battery indicator Updatable software Type of data storage
Indication options (alarm/flash/etc.) Updatable circuitry Adjustable time of stimulation
Dispatch service Crush resistant Fast response time
Tracks events in detail Will not tangle Cost
Doesn’t wake the baby Will not overheat Replacement availability
Ability to transfer data Strong connections Not small enough to swallow
Short set-up time Easily adjustable settings

demonstrates elements of a QFD for a system to detect when a baby stops breathing. Table 16.1 shows
examples of additional customer requirements for this QFD. Figure 16.4 is a rendering of a pod that
may be transported by ground vehicle or helicopter to an emergency. A fire protection version must
be accessible to all, including those in wheelchairs, for protection from wild fires. Figure 16.5 is a par-
8
tial QFD for this pod. In this brief overview of QFD, select issues will be highlighted in each room.
Follow both Figs. 16.1 and 16.2 in the house tour below. A completed QFD would rarely fit on a single
page as in these three examples.
Room 1: Customer requirements. These are generated by focus groups, surveys, interviews, etc.
1
The requirements include expecters, spokens, unspokens, and exciters. Expecters are standard fea-
tures that one would expect in a product. Spokens are features that the customer will tell you are
desired. Unspokens are important features that the customer has forgotten, was unwilling to mention,
or did not realize at the time. These first three categories must be addressed for consumer satisfaction.
The last category, exciters, are typically unique features of your product that will boost sales. Since
technology advances quickly and competition is stiff, today’s exciters will become next quarter’s
spokens and next year’s expecters. This is evidenced in both the computer and consumer electronics
industry. Some requirements are directed toward function and others toward form. Requirements also
may include price, serviceability, etc.
Room 2: Identification of the customers and their ranking of the customer requirements. When
identifying your customers, consider internal customers as well. Are you developing a product that
your manufacturing personnel can produce? Does your sales force need a claim of cheapest, fastest,
or lightest? List salespersons, assemblers, etc., as customers in the house of quality. Figure 16.1 primar-
ily illustrates external customers that an engineer new to this field may be unfamiliar with. Multiple
house-of-quality diagrams may need to be generated to handle all the customers on manageable-sized
diagrams. In addition to the primary customer, the device user, other customers include all who must
interact with it. For example, will a family member or health professional need to customize or maintain
this device? How about the insurance agency or organization that may be paying for it? Have their
requirements been addressed? Typically, each class of customer ranks the importance of each require-
ment. One common ranking scheme is to have the customer list all requirements in the order of impor-
tance beginning with one. Although this forces the customer to distinguish between requirements, it
does not show the relative weight of each. A second approach is to mark each requirement that is
extremely important with a 5, very important with a 4, and continue down to 1 for minimally important.
(Blank can be reserved for not important at all.)