Module 2 – Measure

Chapter 3: Engineering Characteristics/Specifications and Benchmarking

Benchmarking and Engineering Specification

Click on the left arrow to see each definition!

Determining the How

Once the design team has identified the WHO (customer) and WHAT (customer requirements), the next step is to determine the HOW. As engineers, the team will need to develop engineering characteristics/features/functions to satisfy the customer.

For example, consider designing a new vehicle. A stated need/want by the customer might be,

“I need a lot of room in my car because I have two kids and a dog and we take cross-country trips”.

This translates into the customer requirement :

The car must be roomy.

To engineer a vehicle that meets this customer requirement, we must cast “roomy” into quantitative metrics or design features that we can:

  1. Assess “on paper” using our modeling skills;
  2. Measure once prototypes and production versions of our design are built;
  3. Justify our choices to management.

Suitable “metrics” might be:

  • “Rows of seats (#)”
  • “Interior volume (cubic feet)”
  • “Headroom (inches),” etc.

A corresponding feature might be:

  • “Fold down seats.”

Note each metric has an associated unit. Specific features may or may not exist, and thus have no units. The list of design criteria should be based on careful analysis of the customer’s wants/needs, analysis of existing products and systems, and extensive discussion amongst the team.

In summary, HOW refers to:

The technical features, functionality, and characteristics that meet customer requirements, which form the “attic “of the house or How to Satisfy the Customer. The Relationship Matrix room of the House is used to assess these using the Customer Requirements using 1, 3, and 9. This is shown in your DMADVR Toolbox, in the tab titled,  QFD w_DM.

The rooms or parts of the House of Quality are represented like a floor plan
House of Quality Rooms

Let Us Revisit MIRE TECH

The MIRE TECH design team first developed their customer requirements (CR) and rankings. Next, the team brainstormed engineering features/characteristics/functions that would satisfy these customer requirements. Asking HOW around the CRs assisted the team in developing the engineering features/characteristics/functions. The team brainstormed a list of quantifiable metrics and/or features that can be correlated to the customer requirements. Each metric must have an associated unit. If there is an “industry standard” definition of a particular metric, use the standard metric.

Specifications and their Importance

Now let’s take another look at our design team’s development of a new chocolate chip cookie. The design team gathered information from the voice of the customer and determined the Customer Requirements and their rankings.

Now the Chocolate Cookie Design (CCD) team can brainstorm around Engineering Specifications (functions/features/characteristics) to determine HOW the CRs will be satisfied by your CCD engineering team.

Voice of the Customer: Customer Requirements
Ranking Based on Customers’ needs/wants, Define Customer Requirements
9 Good Texture
9 Generous Portions
3 Taste Good
3 Low Price
1 Appetizing Appearance

Now, the team needs to relate the customers’ requirements to the engineering metrics and features. This is a team decision based on thoughtful discussions and research in order to justify the correlations. This is sometimes referred to as the correlation or relationship matrix of the House of Quality.

MIRE TECH Design Team used the following scale to assess/rank the relationship between CRS (What) and the Engineering Specifications, Features, Functions, and Characteristics:

  • 9 – Strong relationship
  • 3 – Moderate relationship
  • 1 – Little to no relationship

House of Quality: How It is Built

Units of Measurement

Additionally, each /function/characteristic can be assessed in terms of their “direction”, up or down. In other words, from an engineering perspective, are you increasing or decreasing performance when meeting each Customer Requirement. A House Of Quality format is not always uniform. Some formats place units in the attic (top center) or foundation (bottom center). Some use up and down arrows vs. +/-. It is important that you review the form provided in the course to ensure compliance.

Target Values

The House of Quality (HoQ) provides a foundation to use benchmarked or target values as objective measurements to evaluate each characteristic, forming the basement of the house (8.). Compare competition by benchmarking against Engineering Specifications.

Mire Tech Team has calculated the ranking shown in the spreadsheet below, Mire_Tech_QFD (House of Quality_with DM).  Download the spreadsheet below. Review how the rankings are automatically calculated based on your assessments already provided for the WHAT and HOW in the middle top area of the House of Quality (HoQ). Remember that the WHAT is the customer requirements or What the customer Wants! Also, the HOW is how your design team will satisfy or address What the Customer wants!

MIRE_TECH completed sections 1, 2, 6, 7, 4, and 8. At the bottom of 4. Competition and Concepts are the scores for each of the Competitors and Concepts (Your team’s). In green highlight are the high scorers, and can be used to develop the Benchmarking data!

Review the WHAT (Customer Requirements on the left side. There are two customers: the end user and the entrepreneur.  Reviewing the spreadsheet from left to right the Customer Requirements or the WHAT rows are addressed by the HOW columns. This is the process for engineering design teams to understand WHAT the customer requires/wants and HOW the team will address this in their design.

Occasionally, company cultures allow more than 1,3,9 ranking. It is rare, and won’t be used for ME design courses.

This ranking of the engineering features/functions/characteristics/metrics allowed the team to then identify the ones that have the biggest impact on customer requirements. Additionally, the team may identify target values for each metric and indicate whether each feature listed should be present or absent. Achieving each of the targets should mean that the customer(s) will be satisfied with the team’s design.The bottom part of the table is for Benchmarking or quantifying each competing product/system against engineering features/functions/characteristics/metrics the team developed (HOW). If a particular metric or feature doesn’t fit with a particular competitor, this may mean the team’s list is incomplete. Use appropriate sources. The team may need to make an educated guess and clearly identify that you have guessed. This area allows the team to determine where (measurable) their design needs to be in terms of specifications in moving forward with their selected concept.

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Introduction to Mechanical Engineering Design Copyright © 2023 by Jacqulyn A. Baughman is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License, except where otherwise noted.