P11543: Variable LED Hemispherical Imager

Establish Target Specifications

Table of Contents

Step 1. Prepare the List of Metrics

The table below presents the metrics, or engineering specifications, that will be used by the team to design against.

List of Metrics
Metric No. Metric Importance Units
1 Marginal Resistance Value ohms
2 Needs at least 5 VDC V
3 Pulse Width Modulation %
4 Digital control of each LED bit
5 USB/RS232 port
6 Compatible with MATLAB .m file
7 Can use any power supply Watts
8 6 spectral LEDs and 1 white nm
9 400-650 nm range must be covered nm
10 Adequate spread across spectrum nm
11 White in middle of LED cluster nm
12 Less than 18o cone angle Degrees
13 Separate output for each LED pin #
14 Change current across LED amp
15 T1-3/4 casing
16 2 clusters of 7 LEDs
17 Less than 30 seconds to disconnect sec
18 Replace individual LEDs under 30 seconds sec
19 Cluster diameter under 2 inches inch
20 Half degree resolution at all nodes Degrees
21 At least 324 nodes node
22 Under 100 kg kg
23 1 meter diameter hemisphere m

The metrics, or engineering specifications, that you created in the preceding list should be directly related to the customer needs. In other words, if you have created an engineering specification, it should have some relationship to a need imposed by the customer or the marketplace. Use the table below to map your customer needs against the metrics (or engineering specifications). In many design and product development circles, the rows along the left is often referred to as the voice of the customer, while the columns across the top are often referred to as the voice of the engineer.

Customer Needs as Related to Engineering Metrics Matrix
Needs and Metrics Engineering Metric 1 Engineering Metric 2 Engineering Metric 3 Engineering Metric 4 Engineering Metric 5, etc.
Customer Need 1 x x
Customer Need 2 x
Customer Need 3 x x
Customer Need 4, etc. x x x

Step 2. Collect Competitive Benchmarking Information

Relatively few Sr. design projects start from a clean sheet of paper. In most cases, there are some baseline solutions or products that could meet the vast majority of the customer's needs.

Write one or two paragraphs about each benchmark solution from the market place. Include a picture of the product, preferably illustrating the product in use or operation.

Benchmark 1
Describe the first benchmark solution here.
Benchmark 2
Describe the second benchmark solution here.
Benchmark 3
Describe the third benchmark solution here.

Use this table below to compare how pre-existing solutions should compare against the design team's efforts. See the example Table 5-6 on Page 80 of the text by Ulrich and Eppinger.

Competitive Benchmarking Matrix
Metric No. Need Nos. Metric Importance Units Benchmark 1 Value Benchmark 2 Value Benchmark 3 Value
1 Need 1,3
2 Need 2,6
3 Need 1,3
4 Need 1,3
5 Need 4
6 Need 5

Step 3. Set Ideal and Marginally Acceptable Target Values

Given the customer needs, awareness of the marketplace, and resource limitations of the current project, assign preliminary engineering specifications on each of the metrics. In addition to setting the nominal or target value or each specification, provide guidance to the team on the ideal value or direction that the team should strive for, once the nominal target values have been realized.

List of Metrics
Metric No. Need Nos. Metric Importance Units Marginal value Ideal Value
1 Need 1,2
2 Need 2,4
3 Need 5
4 Need 6
5 Need 5,1
6 Need 6,2

Step 4. Reflect on the Results and the Process