HOMEWORK ASSIGNMENT #1
CUSTOMER NEEDS, FUNCTIONAL DECOMPOSITION, CONCEPT SELECTION
Note: All homework have to be typewritten and submitted via Blackboard as a single file (either in .doc or .pdf format).
Problem 1 [20 pts.]
Develop a QFD diagram for an electrically powered steam iron. Start with Customer Requirements broken into two main
categories: Ironing Performance and Handling & Use. List at least 5 items in each. Map them into Design Characteristics
(at least 10), using the Relationship Matrix, and add Trade‐off Matrix.
Problem 2 [10 pts.]
Using the information contained in the matrix below, rank the alternative ways of renting an apartment by a student in
close proximity to campus. Clearly identify the best alternative. Explain the process by which you have arrived at your
conclusion. First, perform the process with all requirements as having the same importance (e.g., equal weights) and
then run your analysis again and apply modify the levels of importance (e.g., unequal weights) according to your own
preferences. Compare the results and explain the differences.
| Choice Requirements |
Importance (or Weight) |
Dormitory | Apt. 1 | Apt. #2 | Apt. #3 |
| Low cost | D A T U M |
S | ‐ | S | |
| Spacious | ‐ | S | ++ | ||
| Proximity | ‐ | S | ++ | ||
| Bus stop close | + | ++ | ++ | ||
| Pets allowed | + | ++ | + | ||
| View | +++ | ++ | ++ | ||
| Grocery close | ‐ | ‐ | S | ||
| Sum of + | |||||
| Sum of ‐ | |||||
| Sum of S | |||||
| RANK |
Problem 3 [20 pts.]
Consider a MissileStorm Nerf Gun (see figure an related text), which shoots foam darts. Create a functional model of the
toy, starting first with the black box model (general input‐output model) and then create more detailed model,
representing its operation.
The piston is pulled back against the force of the spring and locked in place, storing potential
energy. The chamber’s volume is now large. When the trigger is pulled, the piston is released and
the spring forces it forward, causing the volume of the chamber to decrease and a rise in
pressure. The resulting increase in air pressure applies a force to all the surfaces inside the
chamber, including the back side of the projectile. Because the projectile is relatively movable
compared to the rest of the components of the gun, the force exerted on it causes it to move
forward. The projectile is expelled from the body of the nerf gun.
