P08002: Automated Parallel Bars
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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.

This has to be updated to be consistent with list of needs

List of Metrics
Metric No. Metric Importance Units
1 Rigid Under Max Load 5 lbs.
2 Minimum Vertical Deflection 5 inches
3 Minimum Horizontal Deflection 5 inches
4 Shield all moving components 5 Yes/No
5 Creates no additional obstacles 5 Yes/No
6 Shield all greasy/dirty components 5 Yes/No
7 Securely fastened in place 5 Yes/No
8 Intervals of height adjustment 5 inches
9 Parallel to Floor 5 degrees
10 Total Time to Adjust 5 seconds
11 Maximum Force Required by user 5 pounds
12 Torque Required 1 ft-lbs.
13 Spacing of bars at base 3 ft.
14 Area of Footprint 3 sq. feet
15 Range of Motion 5 inches
16 Elevation 5 inches
17 Visible Display 4 yes/no
18 Difference in bar heights 1 inches
19 Cycles to failure 4 cycles
20 No modification to existing supports 5 Yes/No
21 Distance to power source 2 feet
22 Man-hours of Naz. Maintenance 3 $
23 Building modifications for relocation 3 $
24 Material Costs for relocation 3 $
25 Maintenance personal can explain work needed 2 Yes/No
26 PT student can read and operate machine 4 Yes/No
27 NSF budget 5 $

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

QFD Diagram of Customer Requirements & Engineering Needs

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 - Trailer Jack
Broke down a trailer jack into all components, took careful note of how it worked, and took careful measurments. In addition to sketches, pictures were also taken, as shown below.
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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 Rigid Under Max Load 5 lbs. 300 400
2 Need 2, 7 Minimum Vertical Deflection 5 inches based on current
3 Need 3, 7 Minimum Horizontal Deflection 5 inches based on current
4 Need 4, 6 Shield all moving components 5 Yes/No safety analysis
5 Need 5 Creates no additional obstacles 5 Yes/No safety analysis
6 Need 8 Shield all greasy/dirty components 5 Yes/No safety analysis
7 Need 9 Securely fastened in place 5 Yes/No yes yes
8 Need 10 Intervals of height adjustment 5 inches >1 1
9 Need 11 Parallel to Floor 5 degrees 0.05 0
10 Need 12, 14 Total Time to Adjust 5 seconds 90 60
11 Need 12 Maximum Force Required by user 5 pounds >10 8
12 Need 13 Torque Required 1 ft-lbs. >5 4.5
13 Need 15 Spacing of bars at base 3 ft. 3 3
14 Need 15, 20 Area of Footprint 3 sq. feet 100 50
15 Need 16 Range of Motion (change in height) 5 inches 15 17
16 Need 16 Elevation (from floor) 5 inches 29-42 27-44
17 Need 17 Visible Display 3 yes/no no yes
18 Need 18 Difference in bar heights 1 inches 0.25 <0.125
19 Need 19, 21 Cycles to failure 4 cycles 160000 320000
20 Need 22 No modification to existing supports 5 Yes/No yes yes
21 Need 23 Distance to power source 2 feet 5 1
22 Need 24 Man-hours of Naz. Maintenance 3 hours 3 2
23 Need 24 Building modifications for relocation 3 $ 400 200
24 Need 24 Material Costs for relocation 3 $ 100 50
25 Need 25 Maintenance personal can explain work needed 2 Yes/No yes yes
26 Need 26 PT student can read and operate machine 4 Yes/No yes yes
27 Need 27 NSF budget 5 $ >1500 1500-install cost

Step 4. Reflect on the Results and the Process

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