View
213
Download
0
Category
Preview:
Citation preview
Tinkertoy Tower Design
Tinkertoy Tower Design
Post Mortem DiscussionPost Mortem Discussion
The point of the exerciseThe point of the exercise
“It is your job to discover the system requirements.”
Who is the customer?
Exercise consists of 2 phases: Design (40 minutes) Implementation (15 minutes)
“It is your job to discover the system requirements.”
Who is the customer?
Exercise consists of 2 phases: Design (40 minutes) Implementation (15 minutes)
Design phaseDesign phase
Planning (problem & solution) Classes of components Deliverables are a design and
its inventory of technologies Finding & fixing issues cheap Deadline (40 min)
Penalty (large) Bonus (smaller)
Ends with PDR
Planning (problem & solution) Classes of components Deliverables are a design and
its inventory of technologies Finding & fixing issues cheap Deadline (40 min)
Penalty (large) Bonus (smaller)
Ends with PDR
Implementation phaseImplementation phase
Build Specific components
(objects) Deliverable is a prototype
Must pass system test Resolve unplanned issues
but at a steep cost Deadline (15 min)
Penalty (absolute) Bonus (large)
Ends with CDR
Build Specific components
(objects) Deliverable is a prototype
Must pass system test Resolve unplanned issues
but at a steep cost Deadline (15 min)
Penalty (absolute) Bonus (large)
Ends with CDR
Operations phaseOperations phase
Not addressed in exercise Customer will operate
Design must address maintenance and other life cycle issues
Never ends
The clearer the milestones between phases, the better
Not addressed in exercise Customer will operate
Design must address maintenance and other life cycle issues
Never ends
The clearer the milestones between phases, the better
Construct Figures of MeritConstruct Figures of Merit
All choices are trade-offsAll choices are trade-offs
Schedule always mattersSchedule always matters
Prototypes must pass tests
Prototypes must pass tests
Include cost of test equip. Environment is described
Flat hard surface Free standing
Minimum test is stated, but
Additional requirements are always present
Include cost of test equip. Environment is described
Flat hard surface Free standing
Minimum test is stated, but
Additional requirements are always present
Discovering requirementsDiscovering requirements
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
Design lifeDesign life
Implicit in every project Should be explicitly stated Y2K was a design life issue Observatory systems can
have an especially long life STB running since 20 July
1993 Lifecycle planning
Retirement requirements Evolving environments
Implicit in every project Should be explicitly stated Y2K was a design life issue Observatory systems can
have an especially long life STB running since 20 July
1993 Lifecycle planning
Retirement requirements Evolving environments
Analyze RisksAnalyze Risks Unprecedented challenges
Software projects are notorious for collapsing under own weight
Either a project is tied to core mission of the organization
or It isn’t - which is riskier?
Unprecedented challenges
Software projects are notorious for collapsing under own weight
Either a project is tied to core mission of the organization
or It isn’t - which is riskier?
Implementation IssuesImplementation Issues
Different technologies have different acquisition costs
Different recurring costs Integration issues Quality assurance Maintenance and reliability Availability of
HW/SW/personnel
Different technologies have different acquisition costs
Different recurring costs Integration issues Quality assurance Maintenance and reliability Availability of
HW/SW/personnel
All design is evolutionary All design is evolutionary
Improve Tinkertoy exercise? Display example tower?
“Here is a 60’ tower. It earns minus $33K. Why?”
Swap designs w/ other teams?
Hand out requirements with less prodding from teams?
One shared can of Tinkertoys during design phase?
Improve Tinkertoy exercise? Display example tower?
“Here is a 60’ tower. It earns minus $33K. Why?”
Swap designs w/ other teams?
Hand out requirements with less prodding from teams?
One shared can of Tinkertoys during design phase?
Not applicable to software?
Not applicable to software?
The tower exercise is only a cartoon model of real towers
No civil engineering, per se No beams or trusses No welds or rivets No tension or compression
The tower exercise is only a cartoon model of real towers
No civil engineering, per se No beams or trusses No welds or rivets No tension or compression
The essence of Systems The essence of Systems
System engineering is responsible for identifying and satisfying the life cycle requirements.
One problem Many solutions
System engineering is responsible for identifying and satisfying the life cycle requirements.
One problem Many solutions
Recommended