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The Canadian Advanced Nanospace eXperiment (CanX) program at the University of Toronto's Space Flight Laboratory provides rapid, cost effective access to space through the use of micro- and nanosatellites. The primary focus of this thesis is the development of the CanX-4/-5 nanosatellite mission, which is intended to demonstrate precise, autonomous formation flying. This involves the development of nominal and contingency operations, system budgets, and requirements to produce a complete system architecture. Also described is the assembly, integration, and testing of flight hardware for this mission. In addition, this thesis addresses the on-orbit operation of CanX-2 and CanX-6/NTS, as it relates to operations planning for CanX-4/-5. The ground station operations for these two nanosatellite missions are described, with particular focus on payload operations and contingencies resulting from on-orbit anomalies. This experience is then related to the development of the CanX-4/-5 ground station software architecture.

The Canadian Advanced Nanospace eXperiment (CanX) program at the University of Toronto's Space Flight Laboratory provides rapid, cost effective access to space through the use of micro- and nanosatellites. The primary focus of this thesis is the development of the CanX-4/-5 nanosatellite mission, which is intended to demonstrate precise, autonomous formation flying. This involves the development of nominal and contingency operations, system budgets, and requirements to produce a complete system architecture. Also described is the assembly, integration, and testing of flight hardware for this mission. In addition, this thesis addresses the on-orbit operation of CanX-2 and CanX-6/NTS, as it relates to operations planning for CanX-4/-5. The ground station operations for these two nanosatellite missions are described, with particular focus on payload operations and contingencies resulting from on-orbit anomalies. This experience is then related to the development of the CanX-4/-5 ground station software architecture.

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This thesis describes an investigation of the performance and further development of the lithium-sulphuryl chloride cell for high rate applications.

This thesis presents a framework for formal system development. The framework is called `RD' which is short for `Reasoning about Designs'. RD integrates proof, development and diagnostic modes of reasoning. Many commonly studied formalisms are shown to be consistent with this framework. A large example based on an industrial problem is given to demonstrate RD. The integration of system design and management is achieved by unifying formal software engineering methods and model-based reasoning. RD formally specifies a complete toolkit for performing system development and then re-using the development as the system description for diagnostic reasoning. RD does not restrict the contributing system analysis methods, rather it maps out and defines the entities and relations common to both. The framework is, in principle, extensible to support other forms of reasoning. The ground technical mechanism of the framework is a novel view of formal system development based on a general implementation relation. Implementation relations are widely studied in formal methods in software engineering where they are often referred to as `refinement'. RD allows refinement relations to be defined in a way that makes expected behaviours and faults of system implementations explicit. Furthermore, a case is made that all well known forms of refinement implicitly support diagnostic reasoning as they can be restated within the framework. RD is an integrated and completely rigorous approach to the core system building tasks of design and management. Despite the large amount of technical detail, the following discussion can be seen as raising many issues that relate to engineering in general. In particular, a formal engineering process should have benefits beyond just the delivery of systems that satisfy their specifications.

This work examines the belief system underlying computer-based systems development, by reference to an analogy with a model of scientific research due to Kuhn. Kuhn's model describes 'scientific communities', each united by an underlying many-faceted belief system, the 'disciplinary matrix', which forms a constellation of commitments shared by the members of these communities. A scientific community is compared here with the community of computer-based systems developers and its sub-groups. The division of the developers of computer-based systems development methods and tools into schools based on paradigmatic differences is paralleled with Kuhn's view of a scientific discipline at the early, pre-science, stage. The use of a computer-based systems development method in practice, and informal computer-based systems development activities, are paralleled with Kuhnian normal science, working within the paradigm of the discipline and of the techniques employed. This parallel provides a framework for structuring the explicit and implicit assumptions and models which form the craft knowledge underlying computer-based systems development theory and practice. Following a search for elements of the disciplinary matrix in the theory of computer-based systems development, as described in textbooks, and in its practice through interviews with developers, the results of action research and reports of systems development failures, it is concluded that the analogy with Kuhn's view of scientific activity is justifiable, and that articulation and examination of the implications of the analogy can reveal useful information to assist in describing and improving computer-based systems development. The results of this search are presented in terms of the specific beliefs and models identified. It is suggested that, as future research, the Kuhn-based model of computer-based systems development should be extended into a detailed investigation into the effects of individual elements of the disciplinary matrix, either individually or in combination, on the mind set of the computer-based systems developer.

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