5
Importance of Integration
classified into two categories: those failures that are a result of all that transpired before integration and those failures that are a direct consequence of
the integration activities. Integration failures that are inherent in the development work prior to integration can be a symptom of a poorly defined
problem (i.e., redefined or corrected before integration is completed); a
missed stakeholder or stakeholder requirements and therefore unknown,
incorrectly interpreted, or ignored needs; a system design or architecture
that inadequately responds to the stakeholder requirements or needs; or
mismanagement of the efforts leading up to and including the integration
activities (specifically any subprocess of planning, directing, controlling,
communicating (Kasser and Shoshany 2000), organizing, and team-building). Integration failures that occur during the process of integration have
several root causes, including mismanagement (focused on poor alignment
of resources with required tasks, poor communication, and unreliable functionality which is attributable to one or another object) and poor integration
skills, tools, or test equipment. Within the integration stage of work, communication between team members needs to be called out specifically as a
key issue to succeed with integration. Beyond simply communicating what
members of the team are doing and why, systems engineers with broader
knowledge of the stakeholders, the implications of the design and the architecture, acceptance criteria, manufacturing, user intentions, and key sensitivities of stakeholders will improve the effectiveness of the integration team
in achieving functional interoperability. And, engineers with specialization
and expertise will improve the efficiency of integration. Both background
specialties are important to successful integration (Nissen et al. 2006).
Identifying the category of integration failure from an analysis of case
studies helps (1) to recognize the relation between formative work in systems
engineering and system integration and the integration activities, (2) to
provide insight into identifying what to look for and improve in the formative work, and (3) to develop a better sensitivity to the need for recursive
thinking rather than iterative thinking.
Hubble Space Telescope Systems Engineering Case Study
Introduction
Even with adaptive optics,* viewing stellar objects from Earth-based
telescopes is limited by the Earth’s atmosphere and environmental effects.
* Adaptive optics compensate for much of the Earth’s atmospheric turbulence that reduces the
“seeing” to less than the diffraction-limited performance of a telescope. The mechanism of
adaptive optics is to compensate for errors in a spherical wavefront by changing the longitudinal location of segments of the optical system. The effect is to correct for deviations in the
incoming radiation by distorting one or more of the optical elements in the optical train of
the telescope (Tyson 1991).
Importance of Integration
classified into two categories: those failures that are a result of all that transpired before integration and those failures that are a direct consequence of
the integration activities. Integration failures that are inherent in the development work prior to integration can be a symptom of a poorly defined
problem (i.e., redefined or corrected before integration is completed); a
missed stakeholder or stakeholder requirements and therefore unknown,
incorrectly interpreted, or ignored needs; a system design or architecture
that inadequately responds to the stakeholder requirements or needs; or
mismanagement of the efforts leading up to and including the integration
activities (specifically any subprocess of planning, directing, controlling,
communicating (Kasser and Shoshany 2000), organizing, and team-building). Integration failures that occur during the process of integration have
several root causes, including mismanagement (focused on poor alignment
of resources with required tasks, poor communication, and unreliable functionality which is attributable to one or another object) and poor integration
skills, tools, or test equipment. Within the integration stage of work, communication between team members needs to be called out specifically as a
key issue to succeed with integration. Beyond simply communicating what
members of the team are doing and why, systems engineers with broader
knowledge of the stakeholders, the implications of the design and the architecture, acceptance criteria, manufacturing, user intentions, and key sensitivities of stakeholders will improve the effectiveness of the integration team
in achieving functional interoperability. And, engineers with specialization
and expertise will improve the efficiency of integration. Both background
specialties are important to successful integration (Nissen et al. 2006).
Identifying the category of integration failure from an analysis of case
studies helps (1) to recognize the relation between formative work in systems
engineering and system integration and the integration activities, (2) to
provide insight into identifying what to look for and improve in the formative work, and (3) to develop a better sensitivity to the need for recursive
thinking rather than iterative thinking.
Hubble Space Telescope Systems Engineering Case Study
Introduction
Even with adaptive optics,* viewing stellar objects from Earth-based
telescopes is limited by the Earth’s atmosphere and environmental effects.
* Adaptive optics compensate for much of the Earth’s atmospheric turbulence that reduces the
“seeing” to less than the diffraction-limited performance of a telescope. The mechanism of
adaptive optics is to compensate for errors in a spherical wavefront by changing the longitudinal location of segments of the optical system. The effect is to correct for deviations in the
incoming radiation by distorting one or more of the optical elements in the optical train of
the telescope (Tyson 1991).