JJ & E Research Specialty Engineering as an Element of Systems Engineering INCOSE MEETING (Enchantment Chapter) August 9, 2006 Murray Elowitz JJ & E Research Corp Greenview NE Albuquerque, NM (505)

JJ & E Research Aug 9, 2006 M. Elowitz2 To discuss how System Engineers include SPECIALTY ENGINEERING in their project Defining Specialty Engineering Where it fits into System Engineering Example 1: Meeting spec Example 2: More subtle Purpose Goal: Maximize effectiveness of specialties to support program success

JJ & E Research Aug 9, 2006 M. Elowitz3 Exercise for the student – define products of each specialty Defining Specialty Engineering Murrays Definition (Todays version) – Specialty Engineering is the collection of those narrow disciplines that are needed to engineer a complete system Some specialty engineering has deliverable functional products, Some specialty engineering is analytic.

JJ & E Research Aug 9, 2006 M. Elowitz4 What are specialties SAMPLE LIST (For integrated hardware/software/data systems) RELIABILITY, MAINTAINABILITY, AVAILABILITY Human Factors Safety Electromagnetic Effects Facilities Some people include Logistics Exercise for the student – Name other specialties

JJ & E Research Aug 9, 2006 M. Elowitz5

JJ & E Research Aug 9, 2006 M. Elowitz6 Definitions

JJ & E Research Aug 9, 2006 M. Elowitz7 Typical Org Chart Program Manager System Engineer Specialties RMA Human Factors Safety Etc HardwareSoftwareLogistics Alternate Specialties under System Engineering - Allows careful direction to get to needed results

JJ & E Research Aug 9, 2006 M. Elowitz8 Characteristics Why distinguish the specialties from System Engineering? –Usually a narrow discipline; e.g., RMA –In project team, hard to level load manpower –Practitioners usually want their own identity Why place specialties under System Engineering? –For early phases (Concept Definition through DemVal) SE needs to control or task the specialties Knows where the problems and issues are Understands and performs top-level trades Exercise for the student – Give more reasons

JJ & E Research Aug 9, 2006 M. Elowitz9 In System Engineering Process System Requirements Specialty Require System Design Specialty Design System Analysis Specialty Analysis Preliminary Design Specialty Des, Anal

JJ & E Research Aug 9, 2006 M. Elowitz10 Example 1: Meeting spec Critical Requirement is reliability of commercial aircraft After initial modeling, AVIONICS is critical segment Model Reliability Design Iteration Add Detail Reliability Design Iteration Reflect results Two sides to iteration Underdesign drives loss of sales Underdesign drives warranty costs Overdesign drives cost, possibility loss of sales Did Not Meet Specs Did Not Meet Specs Add Detail Reliability OK Meets Specs

JJ & E Research Aug 9, 2006 M. Elowitz11 Process Reliability Handbook Model System Look up Failure Rates Crunch Present Examples of the kind of system level trades needed instantly System engineer needs special studies What is sensitivity of R to tolerance on controlled temperature? If tightening up on Temp increases vibration, what is system R? If we replace component C with a cheaper one, but use redundancy, will we still meet R spec?

JJ & E Research Aug 9, 2006 M. Elowitz12 Example 2: More subtle Availability – Requires reliability calculations and corresponding MTTRs What if the baseline design makes component K hard to replace, creating a large MTTR? –System tradeoffs may involve lowering MTTR on other components, improving R of component K or others, major design changes to lower Ks MTTR, and so on (and on) –System engineer needs to direct Specialty Engineering to solve the right problem Then SE may need to address whether spec is reasonable

JJ & E Research Aug 9, 2006 M. Elowitz13 System Engineering Golden Rules

JJ & E Research Aug 9, 2006 M. Elowitz14 Summary In the early phases of a program, System Engineering needs tight control over Specialties –Needs to direct resources –Needs to prioritize –Needs responsiveness Putting Specialties under System Engineer provides needed control System Engineer needs to know the capabilities and limitations of each specialty