Formal Design and Verification of Digital PID Gain Scheduling Controllers

The verification process of embedded systems is fundamental for their correct development. Embedded control is a popular choice among the engineering community, making the relationship between control systems and computer science very close. Gain scheduling is a typical approach for safety-critical systems (e.g. jet-engines). It is preferred due to a known route to certification. Nonetheless, stability and performance are hard to prove analytically. Consequently, safety and airworthiness are achieved by extensive testing, and therefore a new way for verification is desirable. Model checking, an exhaustive verification technique, is a part of formal methods. Model checking can aid in detecting ambiguities and collisions in requirements, increasing and improving testing coverage and error detection rate. However, there are still limitations and challenges to model checking. The state-space explosion problem limits its use to realistic dynamic control systems: Computational memory runs out or available data types are not appropriate for modelling. This thesis addresses the formal design and verification of discrete PID gain-scheduled control systems. By the means of a novel abstraction methodology the control problem is resolved in a model checking environment; formally tuning the controller whilst systematically constructing a control schedule. The work in this overcomes typical constraints imposed by model checking. In this manner, the gain-scheduled controller can be efficiently generated and the resulting schedule is correct-by-construction with respect to high level performance requirements. This novel methodology incorporates computer science and control systems tools, proposing an a priori verification approach in contrast to current a posteriori testing activities. By combining computer science and control engineering, the gap between formal methods and control systems is reduced. The next step in this line of research is to analyse the scalability of the approach using more realistic models and design cases; in this manner the state-space explosion problem can be addressed with a divide and conquer approach. Also, a trade-off analysis between benefits and the required effort learning the new approach in a real development cycle must be conducted to assess feasibility and capabilities of the approach

Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project: Current and advanced act control system definition study. Volume 2: Appendices

The current status of the Active Controls Technology (ACT) for the advanced subsonic transport project is investigated through analysis of the systems technical data. Control systems technologies under examination include computerized reliability analysis, pitch axis fly by wire actuator, flaperon actuation system design trade study, control law synthesis and analysis, flutter mode control and gust load alleviation analysis, and implementation of alternative ACT systems. Extensive analysis of the computer techniques involved in each system is included

Measurements, Models, Systems and Design

531 s.

Power Quality in Electrified Transportation Systems

"Power Quality in Electrified Transportation Systems" has covered interesting horizontal topics over diversified transportation technologies, ranging from railways to electric vehicles and ships. Although the attention is chiefly focused on typical railway issues such as harmonics, resonances and reactive power flow compensation, the integration of electric vehicles plays a significant role. The book is completed by some additional significant contributions, focusing on the interpretation of Power Quality phenomena propagation in railways using the fundamentals of electromagnetic theory and on electric ships in the light of the latest standardization efforts

Design and Control of Power Converters 2019

In this book, 20 papers focused on different fields of power electronics are gathered. Approximately half of the papers are focused on different control issues and techniques, ranging from the computer-aided design of digital compensators to more specific approaches such as fuzzy or sliding control techniques. The rest of the papers are focused on the design of novel topologies. The fields in which these controls and topologies are applied are varied: MMCs, photovoltaic systems, supercapacitors and traction systems, LEDs, wireless power transfer, etc

A comparison of processing techniques for producing prototype injection moulding inserts.

This project involves the investigation of processing techniques for producing low-cost moulding inserts used in the particulate injection moulding (PIM) process. Prototype moulds were made from both additive and subtractive processes as well as a combination of the two. The general motivation for this was to reduce the entry cost of users when considering PIM. PIM cavity inserts were first made by conventional machining from a polymer block using the pocket NC desktop mill. PIM cavity inserts were also made by fused filament deposition modelling using the Tiertime UP plus 3D printer. The injection moulding trials manifested in surface finish and part removal defects. The feedstock was a titanium metal blend which is brittle in comparison to commodity polymers. That in combination with the mesoscale features, small cross-sections and complex geometries were considered the main problems. For both processing methods, fixes were identified and made to test the theory. These consisted of a blended approach that saw a combination of both the additive and subtractive processes being used. The parts produced from the three processing methods are investigated and their respective merits and issues are discussed

Reducing risk in pre-production investigations through undergraduate engineering projects.

This poster is the culmination of final year Bachelor of Engineering Technology (B.Eng.Tech) student projects in 2017 and 2018. The B.Eng.Tech is a level seven qualification that aligns with the Sydney accord for a three-year engineering degree and hence is internationally benchmarked. The enabling mechanism of these projects is the industry connectivity that creates real-world projects and highlights the benefits of the investigation of process at the technologist level. The methodologies we use are basic and transparent, with enough depth of technical knowledge to ensure the industry partners gain from the collaboration process. The process we use minimizes the disconnect between the student and the industry supervisor while maintaining the academic freedom of the student and the commercial sensitivities of the supervisor. The general motivation for this approach is the reduction of the entry cost of the industry to enable consideration of new technologies and thereby reducing risk to core business and shareholder profits. The poster presents several images and interpretive dialogue to explain the positive and negative aspects of the student process