ME 102B Concept

## ME 102B Important Issues - Concept Generation

### Concept Generation

A product concept is a description of the technology, working principles, and form of the product. Concepts are expresses as:
Sketch
3-Dimensional model
Brief textural description

Good Concept Generation
Leaves the team with confidence that the FULL space of alternatives has been explored
Reduces the likelihood that the team will stumble upon a superior concept late in the development process
Reduces the likelihood that a competitor will introduce a product with dramatically better performance than the product under development

Common Dysfunctions (during concept generation)
Consideration of only one or two alternatives, often proposed by the most assertive members of the team
Failure to consider carefully the usefulness of concepts employed by other firms in related and unrelated products
Involvement of only one ore two people in the process, resulting in lack of confidence and commitment by the rest of the team
Ineffective integration of promising partial solutions
Failure to consider entire categories of solutions

Clarify the Problem
Clarifying the problem consists of developing a general understanding and then breaking the problem down into subproblems if necessary.
Example: Design a better hand held nailer
Customer Requirements
The nailer will use nails
The nailer will be compatible with nail magazines on existing tools
The nailer will nail into wood
The nailer will be hand-held
The nailer inserts nails in rapid succession
The nailer fits into tight spaces
The nailer is lightweight
The nailer has not noticeable nailing delay after tripping the tool
Engineering Requirements
Nail lengths from 50 mm to 75 mm
Maximum nailing energy of 80 joules per nail
Nailing forces up to 2,000 Newton
Peak nailing rate 1 nail per second
Average nailing reate of 4 nails per second
Ability to insert nails between standard stud/joists (368 mm opening)
Total mass less than 4 kilograms
Maximum trigger delay of 0.25 seconds

#### Step 1: Functional Decomposition

Although some problems can be easily decomposed into the design of functionally independent subsystems, most require a structured effort. We develop a technique for decomposing any problem into smaller, more easily managed parts.
Function can be described in terms of the logical flow of energy (including static force), material, or information. For example, in order to attach any component to another, a person or mechanical assembler must grasp the component, position it and attach it in place. These functions must be completed in a logical order: grasp, position, and then attach.
##### Step 1.1: Find the Overall Function That Needs to Be Accomplished
This is a good first step toward understanding the function. The goal here is to generate a single statement of the overall function on the basis of the customer requirements. All design problems have one "more important" function. This must be reduced to a simple clause and put in a black box. The input to the box are all the energy, material, and information that flow into the boundary of the system. The outputs are what flows out of the system. In the diagrams that follow, energy flow is noted by a thin line, material flow by a thick line and information flow by a dotted line.
##### Step 1.2: Create Subfunction Descriptions
The goal of this step is to decompose the overall function in the black box. When this step is complete, we will have simple descriptions of the subfunctions that need to be accomplished for the product to meet the requirements. Since concepts follow function and products follow concepts, we must fully understand the function before wasting time generating products that solve the wrong problem.
Decomposition by sequence of user actions
Decomposition by key customer needs
##### Step 1.3: Order the Subfunctions
The goal is to add order to the functions generated in the previous step. For many redesign problems this occurs simultaneously with their identification in Step 1.2, but for some processing systems this is a major step. The goal here is to order the functions found in Step 1.2 to accomplish the overall function in Step 1.1.
##### Step 1.4: Refine Subfunctions
The goal is to decompose the subfunction structure as fine as possible. This means examining each subfunction to see if it can be further divided into sub-subfunctions. This decomposition is continued until one of two things happen: "atomic" functions are developed or new objects are needed for further refinement. The term atomic implies that the function can be fulfilled by existing objects.

#### Step 2: Generating Concepts from Functions

Once the functions of the product are understood, the next goal is to generate concepts that satisfy them. Concepts are the means of providing function. Concepts can be represented as sketches, block diagrams, textual descriptions, clay or paper models, or other forms that give some indication of the manner in which the functions are achieved with the
Developing concepts for each function
Combining concepts

Sources for Concept Ideas
Patent search