This project aims at developing new methods of analysis of the stability of fluid flows and flow control. Flow control is among the most promising routes for reducing drag, thus reducing carbon emissions, which is the strongest challenge for aviation today. However, the stability analysis of fluid flows poses significant mathematical and computational challenges. The project is based on a recent major breakthrough in mathematics related to positive-definiteness of polynomials. Positive-definiteness is important in stability and control theory because it is an essential property of a Lyapunov function, which is a powerful tool for establishing stability of a given system. For more than a century since their introduction in 1892 constructing Lyapunov functions was dependent on ingenuity and creativity of the researcher. In 2000 a systematic and numerically tractable way of constructing polynomials that are sums of squares and that satisfy a set of linear constraints was discovered. If a polynomial is a sum of squares of other polynomials then it is positive-definite. Thus, systematic, computer-aided construction of Lyapunov functions became possible for systems described by equations with polynomial non-linearity. In the last decade the Sum-of-Squares approach became widely used with significant impact in several research areas. The Navier-Stokes equations governing motion of incompressible fluid have a polynomial nonlinearity. This project will achieve its goals by applying sum-of-squares approach to stability and control of the fluid flows governed by these equations. This will require development of new advanced analytical techniques combined with extensive numerical calculations. The project has a fundamental nature, with main expected outcomes being applicable to a large variety of fluid flows. The rotating Taylor-Couette flow will be the first object to which the developed methods will be applied. Taylor-Couette flow, encountered in a wide range of industrial application, for a variety of reasons has an iconic status in the stability theory, traditionally serving as a test-bench for new methods. In order to maximise the impact of the research, the project collaborators will conduct targeted dissemination activities for industry and academia in the form of informal and formal workshops, in addition to traditional dissemination routes of journal papers and conferences. Selected representatives from industry will be invited to attend the workshops. Wider audience will be reached via a specially created and continuously maintained web page.

There is great interest in improving the capabilities of autonomous land vehicles, for a diverse range of applications ranging from inspection/repair in nuclear facilities, pipeline inspections, military surveillance, search and rescue, bomb disposal/mine clearance and space exploration rovers to household vacuum cleaners, lawn mowers and pool cleaners. One area of particular interest concerns the navigation of the vehicle and in particular measuring a vehicle's movements or localisation. Odometry or 'dead reckoning' is commonly used to calculate a vehicle's position, and requires some measure of the distance travelled. Currently, the most common technique for measuring odometry involves counting wheel revolutions using wheel encoders. This is prone to errors and inaccuracies, for example due to wheel slippages, unequal wheel diameters, misalignment of wheels, surface roughness and rounding errors due to the discrete sampling of wheel increments. The research proposed here is the development of an improved method of navigation feedback using non-contact optical sensing combined with digital image processing techniques.The research proposed here is the development of an improved method of navigation feedback using non-contact optical sensing combined with digital image processing techniques. The program will involve the construction and demonstration of a test system, the optimisation of processing algorithms and an assessment of its capabilities. This will be followed by the further development of the concept to provide other navigational information about the vehicle's rotation and the detection of vehicle slippages.

The potential for exploiting synthetic jet actuators to delay and control boundary-layer separation in conditions akin to those on aircraft components operating in high-load conditions has attracted much interest in recent years. However, the fundamental mechanism by which synthetic jets interact with incipiently separated turbulent boundary layers subjected to strongly adverse pressure gradient is yet to be fully understood before cost-effective operational flow-control solutions can be sought. This proposal seeks funding for a joint programme of work between groups at Manchester University and Imperial College London, which would exploit complementary strengths and facilities at the two universities. The programme aims to employ a combined experimental (Stereo PIV and other conventional measurement techniques) and computational approach (LES and LES/RANS hybrid modelling) to study the detailed interaction mechanisms, so as to derive generically valid guidelines on optimal separation control in a practical setting. The outcome of the research would be of value to both the academic community and aerospace industry, the latter striving to evolve engineering solutions to flow management with a minimum of moving parts and energy input.

Flutter is a well-studied phenomenon in aircraft wings, and typically affects wings at high flight speeds. Traditionally, aircraft designers sought to avoid flutter altogether; if it was encountered at all during advanced design stages or flight testing, it was dealt with using design fixes and/or inefficient operational modifications. The importance of active flutter mitigation has increased as the wings have become lighter and consequently more flexible over the years. A recent example of active flutter mitigation, which is also commercially deployed, is the outboard aileron modal suppression (OAMS) system incorporated on the Boeing 747-8I. While the details of OAMS are unknown, the phrase "modal suppression" suggests that its design falls within the ambit of traditional wing control methods which use a finite dimensional approximation of the dynamics to design a stabilizing controller. Although this approach allows a designer to tap into the vast family of control techniques for systems described by ordinary differential equations (ODEs), it has three major drawbacks: the ODE approximations tend to have large orders, the states of the ODE are seldom physically meaningful, and the control design process is susceptible to spillover instabilities which can result from an improper modal approximation. Control techniques for systems described by partial differential equation (PDEs), and which avoid finite dimensional approximations, have been evolving steadily in the recent past and promise to do away with both aforementioned drawbacks. The prior work done by the PI led to two new adaptive control techniques that fall within this evolving family of techniques. One of the techniques developed by the PI uses finite dimensional input-output (FDIO) maps that arise naturally for specific input-output pairs for a given PDE. Using FDIO maps, it is possible to convert the control design problem exactly to one for ODEs. Although akin to the risky approach of designing a static output feedback controller in finite dimensional systems, the PI discovered that the structure of the PDE provides a means for expanding the stable envelope of the system even under static output feedback. The PI's work also provided a partial explanation for the underlying stabilization mechanism. The aim of the present project is to develop and demonstrate a low-order adaptive control design technique for flexible wings which exploits the underlying PDE structure of the dynamics effectively, together with a clever reformulation of the control problem. The controller would be based on the PI's prior work [1, 6]. We will provide a major extension of the technique to more realistic, 2-dof wing models and adaptive laws to help the controller deal with modeling and parametric uncertainties. This is key to ensuring practical applicability of the control technique, and requires non-trivial theoretical development as well. We will validate the control technique using wind tunnel testing. The outcome of this project would be a low-order adaptive controller accompanied by analytical performance and stability guarantees. Additionally, the control design would minimize the set of sensors required for the feedback laws, by avoiding ODE approximations as far as possible during the design process. Beneficiaries of this research include the academic community and the aircraft industry, notably those that are involved in developing and deploying aeroelastic solutions. The broader impact of the proposed research has been described elsewhere in the proposal.

Industrial Control Systems (ICS) are used in sectors such as energy, manufacturing, transport, etc., and consequently play a fundamental role in the operation of many critical national infrastructures. In the last few decades ICS have evolved to incorporate new capabilities and connectivity, provided by integrating modern information and communications technology (ICT). However, a significant problem that has emerged due to this new set of technologies and high degree of interconnectivity is that ICS have become exposed to the myriad security problems that beset traditional ICT systems. Of great concern is the trend towards advanced multi-stage attacks against ICS, which continue to emerge. These can involve remote exploitation and lateral movements (pivots) across multiple systems. Recent attacks suggest that traditional crimeware type malware is being adapted explicitly for ICS; e.g. BlackEnergy and Havex exhibit malware modules that appear to have been developed to target ICS features and vulnerabilities. New threats against ICS supporting national infrastructures continue to emerge, and criminal and state entities are known to be targeting such systems. Consequently it is of great importance that we analyse and understand how advanced attacks against ICS behave and can be better detected. Common initial attack vectors include highly targeted spear-phishing against executives or engineers with valuable credentials, or opportunistic watering hole attacks against websites of specific interest to ICS personnel. Following the initial infiltration of an ICS network, the malware will likely try to execute actions including escalating its privileges on the host system, attempting to connect to a command and control server, downloading further payload packages, enumerating the network, pivoting and propagate further, exfiltrating data, and so on. A highly targeted, or "weaponised", payload is likely to enumerate ICS devices on the network or attempt to sniff and identify particular ICS related network traffic. Detecting advanced multi-stage attacks is difficult in IT systems, but approaches towards detection and response for ICS are comparatively less mature. Moreover, attacks discovered in the wild continue to evolve in sophistication. Stopping such attacks demands continual monitoring of the infrastructure and it is difficult to provide operators with targeted security status information in the face of advanced multi-stage ICS threats. This research aims to develop and test an approach that enhances real-time cyber-security monitoring capabilities for networked ICS environments. The objective is to present information to an operator that is more closely correlated to advanced multi-stage threats, rather than individual alerts, thereby improving the ability of the operator to gauge the current security status of the system. A threat measurement based approach will be used to investigate how the real-time cyber-security status of an ICS network environment can be measured in terms of an observable threat presence. It is hypothesised that such a status can be appraised by using suitable metrics, which may be derived by analysing, decomposing and modelling known advanced multistage threats. The analysis will target the development of threat models based on a combination of reported ICS attacks and an investigation of future potential advanced threats based on emerging trends in crimeware. A proposed solution will be implemented and tested in a test-bed environment based on a realistic factory automation environment.