1. Product Development R. Fries
Chapter 6
Product Development
R. Fries

2. Hardware & Software Techniques
Block diagram the system (Visio)
Consider Redundancy – active or standby
Active: failure of one parallel component - the second still works
Standby: failure of component – replacement
MTBF =mean time between failures = 1/λ
Active MTBF=3/(2λ)
Standby MTBF=2/λ

3. Hardware/Software Cont.
Consider component reliability
Vendor assessment (Hx, failure, etc.)
Vendor audit (check facility)
Vendor evaluation (inspect incoming)
Vendor qualification (on-list?)
Consider component history – military & reliability groups, government info bases
Consider safety (FMEA, etc.)

4. Hardware/Software Cont.
Consider component derating
Use 2 watt R in 1 watt situation, decrease failure rate >30% (T, humidity, P, V, I, friction, vibration)
Usage ratio = max stress/stress rating (.5-.9)
Goal is reliability!
Pacemaker example

5. Hardware/Software Cont.
Safety margin must be considered
Safety margin=safety factor-1
=(mean strength/mean stress)-1
Elevator – safety margin~2
Medical devices – Fries - .5 and up.
Load protection must be considered
Environment must be considered (see 112)
Product misuse – consider
Design for variation (6 sigma?)

6. Software Engineering Management
Planning for safety (FDA!)
Planning for risk assessment
Planning for method
Waterfall
Incremental delivery
Spiral
Cleanroom
Code and fix, …

7. Software Engineering Management
Choose design method
Top-down
Data driven
OOP
Language (Assembler/C++/Qbasic?etc.)
Testing
Requirements
Hazard Analysis!!! (FDA)

8. Software Engineering Management
Requirements traceability (FDA)
Software architecture design
Well defined modules (logical)
Other vendor – standalone
Single purpose modules
Cohesion & coupling
Naming
Integration

9. Structured/Unstructured Design Techniques
Computer/database assisted:
Ideation International IWB
TRIZ
Techoptimizer
Others…
Example done in class, another in text

10. Structured/Unstructured Design Techniques
Axiomatic Design
Nam Suh, MIT
Requirements, design parameters, process variables, customer needs = vectors
Try to solve, disassociate functional requirements and design parameters
Highly mathematical
Acclaro Software

11. Structured/Unstructured Design Techniques
Structured, step by step, 8 steps
Pahl and Beitz
Semistructured – Wilcox, Engineering Design for Electrical Engineers, Ulrich and Eppinger Product Design and Development

12. Structured/Unstructured Design Techniques
Reverse engineering
Redesign
Etc.