PRODUCT DESIGN AND DEVELOPMENT
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Sample Answers to Exercises and Thought Questions: Chapter 7

EX 7.1

​Decompose the problem of designing a new barbecue grill. Try a functional decomposition as well as a decomposition based on the user interactions with the product.
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​EX 7.2

Generate 20 concepts for the subproblem "prevent fraying of end of a rope" as part of a system for cutting lengths of nylon rope from a spool.

(Based on a solution by Jim Colgan)

1. Tape the end of the rope.2. Use a torch to melt the end of the nylon rope.
3. Press fit a plastic cap.
4. Dip end of rope into a glue.
5. Tie end of rope in a knot.
6. Use a machine that clips the rope while at the same time applies heat to the end of the rope.
7. Dip the end of the rope into paint.
8. Shrink wrap plastic around the end of the rope.
9. Use a process similar to that used for the end of a shoelace.
10. Attach a steel ring around the rope.
11. Apply a twisting action to the end of the rope to create friction/heat that will ultimately melt the separate strands together.
12. Use an ultrasonic welding process to melt the ends of the rope together.
13. Use a laser to melt the ends of the rope
14. Braid the strands of the rope back into the rope.
15. Use a clothes-pin-like design to clamp the ends of the rope.
16. Wrap a steel wire around the ends of the rope.
17. Wipe a tar-like substance around the circumference at the end of the rope.
18. Design a rope that does not fray.
19. Investigate different types of cutting motions/angles that decrease the probability of fraying to some acceptable limit.
20. Insert the end of the rope into an aluminum sleeve.
21. Tie a piece of fine string, such as fishing string, around the end of the rope.
22. Dip the end of the rope into hot plastic and then into a cooling bath.
23. Attach a rubber band to the end of the rope.

​A database search identified a few interesting US patents that could help a team in developing concepts. Among these are:
Patent #
Year
Title
4785039
1988
Glass Fiber Size and Impregnant Compositions
4473432
1984
​Dot Heat Stapling
EX 7.3

Prepare an external search plan for the problem of permanently applying serial numbers to plastic products.

External search entails investigating several sources of information related to the problem at hand. These sources would typically include: lead users, experts, patents, literature, and benchmarking. For the problem of applying serial numbers to plastics, one could search the following:

Lead users:
Lead users would include manufacturers of products using plastic enclosures where some tracking is required, such as in the electronics, aerospace, or defense industries. The process of investigating customer needs should also help to identify who the lead users might be.

Experts:
Experts might include materials scientists with specialization in plastics such as engineering professors, manufacturing engineers, vendors of plastic materials such as GE Plastics, and manufacturers of labeling equipment.

Patents:
There are many existing patents in this area. Relevant concepts can be identified through a patent database search.

Literature:
There are numerous journals and trade publications to be considered, including: Journal of Manufacturing Systems, Manufacturing Review, Plastics News, Design News, etc.

Benchmarking:
To find related products to benchmark, the areas in which to search should be defined quite broadly. Benchmarking should include an analysis of the following related products: page numbering machinery, laser scribing, and labeling equipment. The team should also investigate how several manufacturers affix serial numbers to many types of products, such as computers and computer equipment, calculators, radios, watches, automobiles, machines, etc. The search should not be limited to plastic products.

TQ 7.1

What are the prospects for computer support for concept generation activities? Can you think of any computer tools that would be especially helpful in this process?

Computer support for concept generation can take on many forms. We already have the assistance of computer-access databases, which provide an invaluable source of information including patents, vendors, customers, literature, etc. There are also word-association programs (e.g., Idea Fisher software) that can be useful to assist in generating ideas and concepts. Maybe there are other forms of computer assistance that can help design teams.

Design researchers in several disciplines have been working for the past 20 years on problems related to creativity and concept design. Researchers have applied search techniques, pattern recognition tools, functional decomposition, and various artificial intelligence ideas to the problem of automatic, computer-based concept generation. So far, researchers have only been able to solve very simple and well-structured problems, such as generating exhaustive lists of permutations and narrowing choices based upon multiple decision criteria.

However, since computers are very good at solving well-structured problems, one research approach would seem to be to develop methods to define concept generation sub-problems in appropriately structured forms. Perhaps this can be done automatically using computers or by humans with computer assistance.

TQ 7.2

What would be the relative advantages and disadvantages of involving actual customers in the concept generation process?

Customers can become intensely excited about assisting a development team to improve product quality by meeting their needs, however there are both advantages and drawbacks of the involvement of customers in concept generation activities.

Here are some advantages:
  • Customers may be more familiar with the use environment than developers, which leads to concepts that fit this environment well.• Customers may be able to express product concepts which address their frustrations more easily than they can express the needs directly. Developers may have missed some important customer needs due to an ineffective process.
  • Keeping the team in contact with customers will keep the team thinking about how to satisfy their needs.
  • The customers will develop some allegiance and pride in the resulting product and confidence that a suitable development process was followed to create the best possible product.

Some disadvantages might be:
  • Customers and developers have goals that are similar but not identical. Both are interested in creating high quality new products, but economically they are at odds.• Customers may become frustrated that the development process is too slow, since they probably do not understand the complex realities of development.
  • The team may be uncomfortable with unfamiliar customers as part of the concept development process.
  • Customers may have no allegiance to the team and the company. They may take the best ideas and other sensitive information and provide this to competitors.

TQ 7.3

For what types of products would the initial focus of the concept generation activity be on the form and user interface of the product and not on the core technology? Describe specific examples.

(Based on a solution by Richard Koch)

The concept generation method involves decomposing the overall problem into sub-problems. Typically, this problem decomposition involves dividing a complex problem into several simpler functional units. Each of these units tends to focus on a single technology or process required for the product. However, for some product development efforts, functional decomposition may not be appropriate. This is especially true for products that are not technology driven or that contain simple, well understood working principles. For such products, the problem may be decomposed into a series of user interactions and/or key customer needs.

The development of a snow shovel might include decomposition into a list of user interactions. The shovel must allow easy gripping, easy lifting with and without a load of snow, be able to scrape snow/ice down to the concrete sidewalk, and must be easily storable. Notice how this list also reflects the probable key customer needs. For a snow shovel, the user interactions are important. From this list of user interactions, the concept generation might be broken up into categories of designs which satisfy gripping, lifting, scraping, and storage issues separately. During the concept selection phase, these separate sub-problems may be combined into a best-solution hybrid concept. There is no inherent technology to be developed in designing a new snow shovel (except possibly that required to manufacture it). Instead, the basic form of the shovel must be carefully considered in order to maximize the user's utility. Although the successful development of a snow shovel involves several technical issues including material and manufacturing processes selection, the ability of the shovel to allow easy user interactions is necessary to make the product superior.

If the product involves very simple technical functions but a lot of user interaction it may be a good candidate for decomposition by the user interfaces. The internal workings of a modern hand-held calculator are so well developed and understood, that the technology is not the difficult part of designing a new calculator. The same internal workings may be found on a dozen different calculators in a price range. Instead, the user interface distinguishes these products and must be carefully considered in order to develop a superior product. The customer is concerned with how easy the keys are to depress, the functions are to use, and the display is to read. Other examples of products with an emphasis on user interactions are: a garlic press, the desk lamp, and a computer mouse.

In reality, most successful products must take both the form and the function into account in the design phase. Athletic equipment is particularly sensitive to success in both the inherent technology involved and the form of the user interactions. Sports equipment often embodies cutting edge technologies and manufacturing techniques and whole products have revolved around a single core idea (i.e., Reebok Pump shoes, or graphite fishing poles). At the same time though, the user interfaces must be carefully considered to allow the peak performance that athletes constantly demand (an athletic shoe that allows good traction but does not fit well or provide good support will not be deemed acceptable in the market).

TQ 7.4

Could you apply the five-step method to an everyday problem like choosing the food for a picnic?

(Based on a solution by Rob Gustafson)

While it is certainly possible to apply the five-step method to an everyday problem, none of us would be very productive if we took the following approach to decide what to eat for every meal. However, if we were interested in satisfying the needs of our picnic guests as best as possible then this method could be quite useful.

Let's assume that we were having an important picnic at which we wanted to impress our guest, such as: a date, potential in-laws, or other VIPs. Then concept generation could be a good way to help ensure that our picnic menu satisfies the dietary needs and desires of our guests. Having already gathered the needs of our guests (i.e., vegetarian, certain likes/dislikes, etc.) then we might approach the five-step method as follows:

Step 1: Clarify the Problem
The challenge here is to "design a menu for a picnic." Some of the assumptions we might have made are:
  • The picnic will be easily transported to our destination.
  • The picnic will not require special technology for delivery or preparation (i.e., no portable microwave ovens).
  • The picnic will be rescheduled if the weather is inclement.
The customer needs that we might have identified include:
  • The menu consists of food that is low in fat.• The menu consists of food that is low in cholesterol.
  • The menu does not include ham.
  • The picnic will include a beverage (alcoholic or non-), a main course, and a dessert.
  • The picnic will feed four adults.
  • The location is already chosen and is reachable only by foot.
  • The budget is limited (after all, we are on a student's budget!).
  • The time to unpack and consume the picnic is reasonable.

These needs could then be translated into target specifications such as:
  • The total fat content in an individual meal does not exceed 8 grams.• The total cholesterol content in an individual meal does not exceed 3 milligrams.
  • No ham on the menu.
  • Each meal will include at least 8 fluid ounces of liquid refreshment.
  • Each meal will provide at least 700 calories and no more than 1,000 calories.
  • The picnic will weigh no more than 10 pounds per person.
  • The volume that each person carries will be no more than 10" X 12" X 18".
  • The total cost of the picnic will not exceed $100.
  • The time to unpack the picnic will not exceed 15 minutes.
  • The time to consume and clean up the meal will not exceed 45 minutes.

We could then decompose the problem into sub-problems by key customer needs such as the beverage, the main course, and the dessert. Then we could choose the main course as the most critical to the success of the picnic (this may also impact our solutions for the other sub-problems such as the beverage). This sub-problem could then be refined, in the case of say a sandwich, into the type of bread, the dressing (mayonnaise or peanut butter), and the filling (meat or vegetable/fruit).

Step 2: Search Externally
To develop solutions for our main course we could look to existing solutions from such sources as:
  • Consulting Experts. We could consult chefs and caterers that specialize in picnic cuisine.
  • Searching Published Literature. We could search through cookbooks and magazines that contain picnic recipes and menu suggestions.

I couldn't think of lead users to identify for our current problem. Nor could I believe that searching patents would be of use. And I don't know of related products that could be suitably benchmarked.

Step 3: Search Internally
For the internal search, the team could individually generate ideas for combinations and preparations of foodstuffs and then meet as a group to generate solution concepts.

​Step 4: Explore Systematically
The team could then explore a sub-problem that constrains the remaining sub-problems through the use of a classification tree. In this example we will assume that the sub-problem that we have selected for a classification tree is the filling in the sandwich. The concept classification tree might look like this:
Picture
The team could also develop a concept combination table. For instance, the table could focus on the sub-problem "sandwich" and the columns could be the components of the sandwich. In this way the team could evaluate new combinations of components to stimulate creative thinking. For this sub-problem the concept combination table might look like:
Bread
Protein Filling
Fruit/Vegetable Filling
Dressing
whole wheat
roast beef
tomato
mayonnaise
white
peanut butter
lettuce
butter
pita
tuna
banana
mustard
rye
egg
jelly
ketchup
This may not be the best example as this list is by no means exhaustive, and it may be possible to have multiple fillings, dressings or even types of bread. If the table was exhaustive, the number of combinations would be unwieldy. One would likely starve (and possibly even be sickened) before considering all the possible combinations.

Step 5: Reflect on the Solutions and the Process

Obviously this process should not occur in a linear fashion; many of these steps should occur in parallel. As each step is being performed, the team should reflect on the new ideas and solutions that are developed. Then the team might revisit other steps to arrive at the best possible solution(s). The final reflection can occur as we enjoy our picnic and we can think about how our next picnic will be improved. Perhaps our solutions could be documented in a new cookbook on picnic cuisine.

TQ 7.5

​Consider the task of generating new concepts for the problem of dealing with leaves on a lawn. How would the a plastic bag manufacturer's assumptions and problem decomposition differ from those of a manufacturer of lawn tools and equipment and from those of a company responsible for maintaining golf courses around the world? Should the context of the firm dictate the way concept generation is approached?

(Based on a solution by Daniel Hommes)

The problem decomposition would differ from one company to the next, based upon the assumptions that each makes about the nature of how leaves should be dealt with.

The bag manufacturing company will most likely decompose the concept generation process down into the steps that it associates with bagging leaves. Those steps might be:
  • Gather leaves into piles
  • Move leaves into bags
  • Seal and dispose of bags

The lawn and garden equipment company would most likely decompose the problem around the steps that would require the use of their tools. Those steps might look like:

Lift leaves from ground
  • Manipulate leaves (shred/compact/etc.)
  • Store leaves
  • Dispose of leaves

The golf course maintenance company would not be constrained to think of the problem as it would utilize a particular product, but instead would be open to any decomposition that would allow for the widest possible set of concepts generated. That decomposition might be:
  • Impart energy to leaves (move them, lift them, burn them)
  • Store leaves (perhaps only temporarily)
  • Discard leaves

The context of the firm should not dictate the way the concept generation is approached, but assumptions about solutions to the problem will invariably be in the minds of the development team members as they begin to decompose the problem. It would do little good for the manufacturer of bags to select a solution that does not use their products, unless they intended to extend their business in new directions. It does not hurt, however, to be aware that other solutions to the problem exist, and to be able to compare the various concepts to understand which are the best. This allows the team to understand what the competition might be capable of if they attacked the problem from a different angle.

In general, it is always best to set aside the constraints and assumptions that a firm might place on a development team regarding core competencies of the firm or required solutions to the problem for the concept generation phase of product development. The understanding that the team can develop about the nature of the problem when unconstrained by corporate hindrances will inevitably lead to a better set of concepts generated.
Copyright 2019 Karl Ulrich, Steven Eppinger, and Maria Yang
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