The house of quality is one of the matrices of the Quality Function Deployment (QFD) that was developed in 1972 at the Mitsubishi shipyard in Kobe, arrived in the United States by the hand of Ford and the Xerox in 1986 and was widely adopted by Japanese, North American and European firms over the course of the last 30 years.
In some applications, it reduced design time by 40% and costs by 60% while maintaining and improving design quality. The QFD collaborates on the cross-functional team of marketing, R&D, manufacturing, and sales, helping them focus on product development. Provides procedures and processes to improve communication by focusing on the customer's language.
The QFD uses four “houses” to integrate the information needs of the product development team. Applications begin at the first house, the House of Quality (HOQ). The team uses the House of Quality together to understand the voice of the customer and translate it into the voice of the engineer.
Voice of the customer
How to identify customer needs
A customer's need is a description, to use your own words, of the benefit that he, she or they want to obtain through the product or service. For example, users of a spirometer (a medical instrument used to measure lung capacity) speak of needs such as "affordable price," "easy to carry," "easy to clean," and "best performing. convenient".
Typically, conversations with clients identify between 100 and 400 needs, including basic needs (what the client assumes a spirometer will do), stated needs (what the client will tell you they want me to do a spirometer) and stimulating needs (those needs that, if satisfied, would delight and surprise the consumer). However, it is difficult for a team to work with 100 to 400 customer needs at a time.
Futuroscope
The most conclusive study to date on Quality Function Deployment (QFD) conducted in the United States suggests that the greatest impact of QFD has been an improvement in the product development process to make it more effective in the long term. Product development for the 21st century will be most effective when marketing, R&D, manufacturing and engineering functions cooperate with each other and especially when they understand each other. The QFD improves communication by providing a tool to implement it. QFD further enhances market success by ensuring that each of these functions is geared toward delivering consumer benefits.
How to structure the needs
In order to handle customer needs, they must be structured in hierarchies. Primary needs, also known as strategic needs, are generally the first 5-10 needs that set the strategic direction for the product. For example "easy to use" is a strategic necessity for a spirometer. Secondary needs, also known as tactical needs, are built from primary needs - each primary need typically generates between 3 and 10 secondary needs. These needs indicate more specifically what can be done to meet the corresponding strategic (primary) need. For example, "easy to use" can lead to "easy to assemble the first time", "easy to operate", "quick to operate" and "easy to calibrate". In most cases,Secondary needs generate highly detailed tertiary needs. These tertiary needs specifically indicate how the design team can meet the secondary needs.
Priority of needs
Customers want their needs to be adequately met, but some needs are higher than others. These priorities help the QFD team make decisions that balance the cost of meeting a need and the benefit the customer receives. For example, if meeting two needs is equally costly, the need that the customer considers the most important should be given higher priority. For example, when designing a spirometer, Puritan Bennett measures importance on a 100-point scale.
Customer perceptions
Customer insights describe how customers evaluate available products based on the ability of the product or service to meet their needs. When we know which products best meet customer needs, with what degree of satisfaction, and if there are differences between the best product and the product that the company makes today, the QFD team can provide the objectives and identify the opportunities for the design of the products.
Design Attributes (The Engineer's Voice)
To meet customer needs, the product (or service) must satisfy measurable needs. For example, if a spirometry system has a print copy, then design attributes might include resolution, ability to prevent image blur, paper loading time, print noise, and misfeed rates. of the paper. These design measurements are the ones that appear at the top of the “house”. They are measured through physical measurement units that become R&D design goals. However, they are not solutions for the product. The solutions come from the second "house" of QFD. If solutions are specified at an early stage, the R&D process is limited exclusively to existing solutions. In this way,more creative solutions could be left out.
Engineering measurements
In the same way that the design team measures available products against customer needs, it also measures competitive products using the physical units specified by the design attributes.
Relationship matrix
The QFD team judges which design attributes influence which customer needs. Each element of the relationship matrix indicates what percentage (if any) of each design attribute affects each of the customer's needs. The idea is to specify the relationships that have the greatest influence, leaving most of the matrix (60-70%) free.
Ceiling matrix
Finally, the ceiling matrix, which appears in Figure 1 indicated with crossed lines, quantifies the physical interrelationships between the design attributes.
Other calculations
The team often estimates cost, feasibility, and technical difficulty when trying to make changes to each of the design attributes.
Next, Professor Víctor Yepes Piqueras, from the Polytechnic University of Valencia, makes an introduction to the operation of the QFD tool, Deployment of the Quality Function, sharing: its background, its definition, the concept of quality house, the cascade of Matrices of the QFD and the benefits that its implementation can generate, evidencing the importance of the client in the development of the products.
