applications of oo system engineering methodology and tools for complex systems9/11/2015 application...

Applications of OO System Engineering Methodology and Tools for Complex Systems 04/21/23

Application of Object Oriented Systems Engineering

Methodology and Tools for Complex Systems

Vinnie Ferrando

Florence Heidel

Joe Marcinek

Copyright, 2003 Harris Corporation. All rights reserved


Topics

• Complex Systems – Systems Engineering Challenges

• Object Oriented (OO) Systems Engineering Analysis and Design Methodology

• Integrated Tools Environment• Automated Document Generation


Some Characteristics of Complex Systems

• Real-time• Distributed, multiple processors• Multiple modes and configurations• System of systems – e.g., National Airspace System

(NAS)

• Multiple customers - Military, Civilian, Commercial

• Complex integration and test

• Multiple complex interfaces – legacy and new

• Transition into existing 24x7 operation


System Engineering - Complex Systems

• Multiple levels of specifications (CDRLs):– Specs: system, subsystem, software, hardware– Specialty engineering: safety, security, RMA, human factors, etc.– Interfaces: ICD, IRS (new and legacy)– Design and construction standards: EMI, RFI, Seismic, Fire, ISO,

RTCA, ICAO, Mil-STD, FAA-STD, etc.

• Tens of thousands of requirements to manage• System Engineering Methodology (e.g., EIA 632)• Subcontract / team member management• Programmatics of development, test, manufacturing,

deployment, transition, logistics, training, etc.


OO Systems Engineering Analysis and Design Methodology

• What is OO?

• OO System Engineering Approach:– Requirements/Domain Analysis– Modeling– Design



• OO: System is a collection of collaborating agent/objects– Object: Abstraction of real-world that contains functions

and data– One object is a black box to another object– Encapsulation: Each object only needs to know how it

interacts with other objects

ObjectA

ObjectB

ObjectC

1) Requests Data from Object B

3) Requests Data from Object C

2) Object B needs data from ObjectC to fulfill Object A request

Object A doesn’t know howObject B fulfills its request;it only cares about the interaction with B.


• Analysis– Use Case-Based Analysis Methodology– Define what the system needs to do from a

user’s/actor’s perspective• Define all of these functions based on customer

requirements


UplinkTDMA Voice

Air Traffic Controller Aircraft

Analog Voice TDMA Packet

Confirmation

System


• Modeling– Model the system to define lower-level objects– Depending on complexity of system, various

levels of analysis are needed


UplinkTDMA Voice



Confirmation



Confirmation

System

Subsystem 1 Subsystem 2

VocodeVoice

SchedulePacketData

Packet


• Example: Modeling using Sequence Diagrams– Emphasize sequence of events– Depict concurrent operations, which are

invaluable for hunting down race conditions

– Capture the time component of interactions between entities at the system and subsystem levels



• Use Cases drive analysis approach for specifying requirements – Use Cases are detailed, structured, text-based

descriptions of interactive usage– Use Cases have overview, pre- and post-

conditions, issues and assumptions for the main flow and alternative flows

– Use Case Analysis and Requirements Generation is an iterative process to handling complex system

– Use Case Analysis at system level, subsystem level as well as process level provides all required capabilities



• Requirements Management– Requirements management is closely linked to modeling– Define lower-level requirements based on models

• Use Case steps become SHALLs for each level of analysis

• Levels of requirements are incorporated into the appropriate CDRL level and allow for customer review

• Defense/Government customers require this strict linkage

– Completeness, consistency, and traceability are attributes of this methodology

– Supplementary requirements are added to the requirements management effort (e.g., Security, Safety, Power, etc.)



• Design– Requirements and models lead to design– Objects are allocated to subsystems– Lowest-level objects become design objects

• Objects will be used for software coding or hardware functionality

• Interaction between objects may become software methods/operations



Integrated Tools Environment

• What is required in an integrated tools environment? – Management of Systems Engineering processes– Integration of Systems Engineering processes

RequirementsManagement

ChangeManagement

ConfigurationManagement

Test

Modeling ? Too difficult to manage!



• Goal: Leverage technology to integrate processes– Changes in one area prompt change in other

affected areas

RequirementsManagement

ChangeManagement

ConfigurationManagement

Test

Modeling

Requisite Pro

ClearQuest

ClearcaseTest Manager

Rose



• Example Approach– One-tool vendor– Vendor integrates well with existing MS Office

Suite– Tools build on methodology…they do not define

the methodology– Use tools designed around OO methodology– Documented and enforced processes



• The process in action:

Action Item is CreatedAction Item is

Linked to RequirementRequirement is changed.

Action Item is Created

Requirement is changed

Action Item is Created

Requirement linked to model…model is changed


Automated Document Generation

• Why Automated Document Generation?– More time engineering, less time documenting– Documents are directly linked to analysis source– Easier review

• Example: Rational SoDA– Scripting language in MS Word to extract documentation

from many sources:• Rose

• Requisite Pro

• Clearcase

• Clearquest

• MS Word

• MS Project

• Others


• SoDA scripts used to generate the following:– Customer Deliverables– Review Packages– Reports for Analysis

Automated Document Generation

Requisite Pro

ClearQuest

ClearcaseTest Manager

Rose SoDApulls togetherintegrated data.


• Why OO and this approach?– Systems are becoming increasingly more

complex• Better tools and techniques are needed to manage

development

– Detailed analysis up-front saves time and cost, ultimately reducing risk when you are ready to build

– Breaks complex system into manageable pieces• With sufficient analysis, developer needs to only

understand assigned objects and how they must interact with other objects…not the whole system

– Tools designed to support this methodology help you manage development

Summary Results


Contact Information

• Vinnie Ferrando, 321-309-7120, [email protected]• Florence Heidel, 321-309-7130, [email protected]• Joe Marcinek, 321-309-7131, [email protected]

Harris Corporation407 John Rodes Blvd.PO Box 9800Melbourne, FL 32902-9800