• Canada
• UKRI|EPSRC close
• 2012 close

There are clear drivers in the transport industry towards lower fuel consumption and CO2 emissions through the introduction of designs involving combinations of different material classes, such as steel, titanium, magnesium and aluminium alloys, metal sheet and castings, and laminates in more efficient hybrid structures. The future direction of the transport industry will thus undoubtedly be based on multi-material solutions. This shift in design philosophy is already past the embryonic stage, with the introduction of aluminium front end steel body shells (BMW 5 series) and the integration of aluminium sheet and magnesium high pressure die castings in aluminium car bodies (e.g. Jaguar XK).Such material combinations are currently joined by fasteners, which are expensive and inefficient, as they are very difficult to weld by conventional technologies like electrical resistance spot, MIG arc, and laser welding. New advanced solid state friction based welding techniques can potentially overcome many of the issues associated with joining dissimilar material combinations, as they lower the overall heat input and do not melt the materials. This greatly reduces the tendency for poor bond strengths, due to interfacial reaction and solidification cracking, as well as damage to thermally sensitive materials like laminates and aluminium alloys used in automotive bodies, which are designed to harden during paint baking. Friction joining techniques are also far more efficient, resulting in energy savings of > 90% relative to resistance spot and laser welding, are more robust processes, and can be readily used in combination with adhesive bonding.This project, in close collaboration with industry (e.g. Jaguar - Land Rover, Airbus, Corus, Meridian, Novelis, TWI, Sonobond) will investigate materials and process issues associated with optimising friction joining of hybrid, more mass efficient structures, focusing on; Friction Stir, Friction Stir Spot, and High Power Ultrasonic Spot welding. The work will be underpinned by novel approaches to developing models of these exciting new processes and detailed analysis and modelling of key material interactions, such as interfacial bonding / reaction and weld microstructure formation.

The biological membrane is a highly organised structure. Many biologically active compounds interact with the biological membrane and modify its structure and organisation in a very selective manner. Phospholipids form the basic backbone structure of biological membranes. When phospholipid layers are adsorbed on a mercury drop electrode (HMDE) they form monolayers which have a very similar structure and properties to exactly half the phospholipid bilayer of a biological membrane. The reason for this is that the fluid phospholipid layer is directly compatible with the smooth liquid mercury surface. The great advantage of this system is that the structure of the adsorbed phospholipid layer can be very closely interrogated electrochemically since it is supported on a conducting surface. In this way interactions with biologically active compounds which modify the monolayer's structure can be sensed. The disadvantage is that Hg electrodes are fragile, toxic and have no applicability for field use in spite of the sensitivity of the system to biological membrane active species. Another disadvantage is that the Hg surface can only be imaged with extreme difficulty. This project takes the above proven sensing system and modifies it in the following way. A single and an array of platinum (Pt) microelectrode(s) are fabricated on a silicon wafer. On each microelectrode a minute amount of Hg is electrodeposited and on each Hg/Pt electrode a phospholipid monolayer is deposited. The stability of each phospholipid layer will be ensured through the edge effect of the electrode. We will use the silicon wafer array to carry out controlled phospholipid deposition experiments which are not possible on the HMDE. We shall also try out other methods of phospholipid deposition. The project will exploit the fact that the microelectrode array system with deposited phospholipid monolayers is accessible for imaging. AFM studies at Leeds have already been used to image temperature induced phase changes in mica supported phospholipid bilayers showing nucleation and growth processes. The AFM system is eminently suitable therefore to image the potential induced phase changes of the phospholipid monolayers on the individual chip based microelectrodes. It is important to do this because the occurrence of these phase transitions is very sensitive to the interaction of the phospholipid layer with biomembrane active species.In addition the mechanism of the phase changes which are fundamentally the same as those occurring in the electroporation of cells are of immense physical interest and a greater understanding of them can be gained through their imaging. We shall also attempt to image the interaction of the layer with membrane active peptides at different potential values. The AFM system will be developed to image the conformation and state of aggregation of adsorbed anti-microbial peptides on the monolayer in particular as a function of potential change. When biomembrane active compounds interact with phospholipid layers on Hg they alter the fluidity and organisation of the layers. This in turn affects the characteristics of the potential induced phase transitions. This can be very effectively monitored electrochemically by rapid cyclic voltammetry (RCV). Interferences to the analysis will be characterised. Pattern recognition techniques will be developed to characterise the electrochemical response to individual active compounds.The project will deliver a sensor on a silicon wafer which has the potential to detect low levels of biomembrane active organic compounds in natural waters and to assess the biomembrane activity of pharmaceutical compounds. The proven feasibility of cleaning the Hg/Pt electrode and renewing the sensing phospholipid layer will facilitate the incorporation of the device into a flow through system with a full automation and programmable operation.

Since the development of the first Kerr-lens mode-locked lasers in 1990, practical femtosecond lasers in a wide variety of configurations have delivered handsomely to a significant number of major scientific developments. It has to be recognised that the application space remains limited by the cost, complexity, skilled-user requirements and restricted flexibility of the current generation of ultrafast lasers. In this proposed joint project we seek to lead the way in the development of a new generation of ultrafast lasers. By adopting a modular approach for laser design we am aiming to demonstrate a platform from which lasers can be designed to address a wide range of user-specific requirements. By taking this approach, lasers for use in communications, for example, will have the necessary high repetition rates and low peak powers whereas for biophotonics high peak powers will be delivered to take full advantage of exploitable optical nonlinearities. We plan to work with vibronic crystals in both bulk and waveguide geometries and semiconductor quantum dot structures as the primary gain media. Although vibronic crystals have been deployed widely in ultrashort-pulse lasers the flexibility offered by conventional laser designs is very limited. To remedy this situation we intend to revolutionise cavity design to enable electrical control of the laser output parameters. For example, we wish to provide a means to users to change from an unmodelocked status to a femtosecond-pulse regime at the flick of switch. Also, by exploiting waveguiding in the vibronic crystals we are confident that we can introduce a new generation of highly compact lasers that will combine many of the advantages of a semiconductor laser with the most attractive features of crystal based devices. In some preliminary work in the Ultrafast Photonics Collaboration we have shown the potential of semiconductor quantum dot structures as broadband gain media that Can support the amplification and generation of femtosecond optical pulses. We now seek to build on those promising results and make the push towards truly flexible ultrafast lasers that will be amenable to external electronic control of the gain and loss components. Progress is expected to lead to a new generation of lasers that can give applications compatibility that far exceeds that available in traditional laser system designs. Within this strategy we plan to employ hybrid approaches where the benefits of semiconductor lasers will be combined with the energy storage capabilities of crystals to deliver compact and rugged sources having pulse characteristics that cover a range of durations, energies and profiles.A major part of this project effort will be devoted to the development of control functionality in ultrafast lasers. The intention is to use direct electrical control of intracavity components to deliver designer options for pulse shaping, modulated data streams, wavelength tuning and tailored dispersion. To ensure that this research is applicable we will evaluate the laser developments in the context of a set of identified demonstrators. These implementations will be used to show how design flexibility can deliver optimised lasers for biological, medical, communications and related applications.We have put together a research team having complementary of expertise and established track records of international excellence in photonics. This project as a whole will be managed from St Andrews University but all three research groups will undertake interactive research on all aspects of the laser development. We are confident that the work of this team will represent cutting-edge fundamental and translational research and it should represent a world leading strength for the UK in the development of new ultrafast lasers.

Since the development of the first Kerr-lens mode-locked lasers in 1990, practical femtosecond lasers in a wide variety of configurations have delivered handsomely to a significant number of major scientific developments. It has to be recognised that the application space remains limited by the cost, complexity, skilled-user requirements and restricted flexibility of the current generation of ultrafast lasers. In this proposed joint project we seek to lead the way in the development of a new generation of ultrafast lasers. By adopting a modular approach for laser design we are aiming to demonstrate a platform from which lasers can be designed to address a wide range of user-specific requirements. By taking this approach, lasers for use in communications, for example, will have the necessary high repetition rates and low peak powers whereas for biophotonics high peak powers will be delivered to take full advantage of exploitable optical nonlinearities. We plan to work with vibronic crystals in both bulk and waveguide geometries and semiconductor quantum dot structures as the primary gain media. Although vibronic crystals have been deployed widely in ultrashort-pulse lasers the flexibility offered by conventional laser designs is very limited. To remedy this situation we intend to revolutionise cavity design to enable electrical control of the laser output parameters. For example, we wish to provide a means to users to change from an unmodelocked status to a femtosecond-pulse regime at the flick of switch. Also, by exploiting waveguiding in vibronic crystals we are confident that we can introduce a new generation of highly compact lasers that will combine many of the advantages of a semiconductor laser with the most attractive features of crystal based devices. In some preliminary work in the Ultrafast Photonics Collaboration we have shown the potential of semiconductor quantum dot structures as broadband gain media that Can support the amplification and generation of femtosecond optical pulses. We now seek to build on those promising results and make the push towards truly flexible ultrafast lasers that will be amenable to external electronic control of the gain and loss components. Progress is expected to lead to a new generation of lasers that can give applications compatibility that far exceeds that available from traditional laser system designs. Within this strategy we plan to employ hybrid approaches where the benefits of semiconductor lasers will be combined with the energy storage capabilities of crystals to deliver compact and rugged sources having pulse characteristics that cover a range of durations, energies and profiles.A major part of this project effort will be devoted to the development of control functionality in ultrafast lasers. The intention is to use direct electrical control of intracavity components to deliver designer options for pulse shaping, modulated data streams, wavelength tuning and tailored dispersion. To ensure that this research is applicable we will evaluate the laser developments in the context of a set of identified demonstrators. These implementations will be used to show how design flexibility can deliver optimised lasers for biological, medical, communications and related applications.We have put together a research team having complementary of expertise and established track records of international excellence in photonics. This project as a whole will be managed from St Andrews University but all three research groups will undertake interactive research on all aspects of the laser development. We are confident that the work of this team will represent cutting-edge fundamental and translational research and it should represent a world leading strength for the UK in the development of new ultrafast lasers.

There are clear drivers in the transport industry towards lower fuel consumption and CO2 emissions through the introduction of designs involving combinations of different material classes, such as steel, titanium, magnesium and aluminium alloys, metal sheet and castings, and laminates in more efficient hybrid structures. The future direction of the transport industry will thus undoubtedly be based on multi-material solutions. This shift in design philosophy is already past the embryonic stage, with the introduction of aluminium front end steel body shells (BMW 5 series) and the integration of aluminium sheet and magnesium high pressure die castings in aluminium car bodies (e.g. Jaguar XK).Such material combinations are currently joined by fasteners, which are expensive and inefficient, as they are very difficult to weld by conventional technologies like electrical resistance spot, MIG arc, and laser welding. New advanced solid state friction based welding techniques can potentially overcome many of the issues associated with joining dissimilar material combinations, as they lower the overall heat input and do not melt the materials. This greatly reduces the tendency for poor bond strengths, due to interfacial reaction and solidification cracking, as well as damage to thermally sensitive materials like laminates and aluminium alloys used in automotive bodies, which are designed to harden during paint baking. Friction joining techniques are also far more efficient, resulting in energy savings of > 90% relative to resistance spot and laser welding, are more robust processes, and can be readily used in combination with adhesive bonding.This project, in close collaboration with industry (e.g. Jaguar - Land Rover, Airbus, Corus, Meridian, Novelis, TWI, Sonobond) will investigate materials and process issues associated with optimising friction joining of hybrid, more mass efficient structures, focusing on; Friction Stir, Friction Stir Spot, and High Power Ultrasonic Spot welding. The work will be underpinned by novel approaches to developing models of these exciting new processes and detailed analysis and modelling of key material interactions, such as interfacial bonding / reaction and weld microstructure formation.

The SUAAVE consortium is an interdisciplinary group in the fields of computer science and engineering. Its focus is on the creation and control of swarms of helicopter UAVs (unmanned aerial vehicles) that operate autonomously (i.e not under the direct realtime control of a human), that collaborate to sense the environment, and that report their findings to a base station on the ground.Such clouds (or swarms or flocks) of helicopters have a wide variety of applications in both civil and military domains. Consider, for example, an emergency scenarion in which an individual is lost in a remote area. A cloud of cheap, autonomous, portable helicopter UAVs is rapidly deployed by search and rescue services. The UAVs are equipped with sensor devices (including heat sensitive cameras and standard video), wireless radio communication capabilities and GPS. The UAVs are tasked to search particular areas that may be distant or inaccessible and, from that point are fully autonomous - they organise themselves into the best configuration for searching, they reconfigure if UAVs are lost or damaged, they consult on the probability of a potential target being that actually sought, and they report their findings to a ground controller. At a given height, the UAVs may be out of radio range of base, and they move not only to sense the environment, but also to return interesting data to base. The same UAVs might also be used to bridge communications between ground search teams. A wide variety of other applications exist for a cloud of rapidly deployable, highly survivable UAVs, including, for example, pollution monitoring; chemical/biological/radiological weapons plume monitoring; disaster recovery - e.g. (flood) damage assessment; sniper location; communication bridging in ad hoc situations; and overflight of sensor fields for the purposes of collecting data. The novelty of these mobile sensor systems is that their movement is controlled by fully autonomous tasking algorithms with two important objectives: first, to increase sensing coverage to rapidly identify targets; and, second, to maintain network connectivity to enable real-time communication between UAVs and ground-based crews. The project has four main scientific themes: (i) wireless networking as applied in a controllable free-space transmission environment with three free directions in which UAVs can move; (ii) control theory as applied to aerial vehicles, with the intention of creating truly autonomous agents that can be tasked but do not need a man-in-the-loop control in real time to operate and communicate; (iii) artificial intelligence and optimisation theory as applied to a real search problem; (iv) data fusion from multiple, possibly heterogeneous airborne sensors as applied to construct and present accurate information to situation commanders. The SUAAVE project will adopt a practical engineering approach, building real prototypes in conjunction with an impressive list of external partners, including a government agency, the field's industry leaders, and two international collaborators.

The SUAAVE consortium is an interdisciplinary group in the fields of computer science and engineering. Its focus is on the creation and control of swarms of helicopter UAVs (unmanned aerial vehicles) that operate autonomously (i.e not under the direct realtime control of a human), that collaborate to sense the environment, and that report their findings to a base station on the ground.Such clouds (or swarms or flocks) of helicopters have a wide variety of applications in both civil and military domains. Consider, for example, an emergency scenarion in which an individual is lost in a remote area. A cloud of cheap, autonomous, portable helicopter UAVs is rapidly deployed by search and rescue services. The UAVs are equipped with sensor devices (including heat sensitive cameras and standard video), wireless radio communication capabilities and GPS. The UAVs are tasked to search particular areas that may be distant or inaccessible and, from that point are fully autonomous - they organise themselves into the best configuration for searching, they reconfigure if UAVs are lost or damaged, they consult on the probability of a potential target being that actually sought, and they report their findings to a ground controller. At a given height, the UAVs may be out of radio range of base, and they move not only to sense the environment, but also to return interesting data to base. The same UAVs might also be used to bridge communications between ground search teams. A wide variety of other applications exist for a cloud of rapidly deployable, highly survivable UAVs, including, for example, pollution monitoring; chemical/biological/radiological weapons plume monitoring; disaster recovery - e.g. (flood) damage assessment; sniper location; communication bridging in ad hoc situations; and overflight of sensor fields for the purposes of collecting data. The novelty of these mobile sensor systems is that their movement is controlled by fully autonomous tasking algorithms with two important objectives: first, to increase sensing coverage to rapidly identify targets; and, second, to maintain network connectivity to enable real-time communication between UAVs and ground-based crews. The project has four main scientific themes: (i) wireless networking as applied in a controllable free-space transmission environment with three free directions in which UAVs can move; (ii) control theory as applied to aerial vehicles, with the intention of creating truly autonomous agents that can be tasked but do not need a man-in-the-loop control in real time to operate and communicate; (iii) artificial intelligence and optimisation theory as applied to a real search problem; (iv) data fusion from multiple, possibly heterogeneous airborne sensors as applied to construct and present accurate information to situation commanders. The SUAAVE project will adopt a practical engineering approach, building real prototypes in conjunction with an impressive list of external partners, including a government agency, the field's industry leaders, and two international collaborators.

The SUAAVE consortium is an interdisciplinary group in the fields of computer science and engineering. Its focus is on the creation and control of swarms of helicopter UAVs (unmanned aerial vehicles) that operate autonomously (i.e not under the direct realtime control of a human), that collaborate to sense the environment, and that report their findings to a base station on the ground.Such clouds (or swarms or flocks) of helicopters have a wide variety of applications in both civil and military domains. Consider, for example, an emergency scenarion in which an individual is lost in a remote area. A cloud of cheap, autonomous, portable helicopter UAVs is rapidly deployed by search and rescue services. The UAVs are equipped with sensor devices (including heat sensitive cameras and standard video), wireless radio communication capabilities and GPS. The UAVs are tasked to search particular areas that may be distant or inaccessible and, from that point are fully autonomous - they organise themselves into the best configuration for searching, they reconfigure if UAVs are lost or damaged, they consult on the probability of a potential target being that actually sought, and they report their findings to a ground controller. At a given height, the UAVs may be out of radio range of base, and they move not only to sense the environment, but also to return interesting data to base. The same UAVs might also be used to bridge communications between ground search teams. A wide variety of other applications exist for a cloud of rapidly deployable, highly survivable UAVs, including, for example, pollution monitoring; chemical/biological/radiological weapons plume monitoring; disaster recovery - e.g. (flood) damage assessment; sniper location; communication bridging in ad hoc situations; and overflight of sensor fields for the purposes of collecting data. The novelty of these mobile sensor systems is that their movement is controlled by fully autonomous tasking algorithms with two important objectives: first, to increase sensing coverage to rapidly identify targets; and, second, to maintain network connectivity to enable real-time communication between UAVs and ground-based crews. The project has four main scientific themes: (i) wireless networking as applied in a controllable free-space transmission environment with three free directions in which UAVs can move; (ii) control theory as applied to aerial vehicles, with the intention of creating truly autonomous agents that can be tasked but do not need a man-in-the-loop control in real time to operate and communicate; (iii) artificial intelligence and optimisation theory as applied to a real search problem; (iv) data fusion from multiple, possibly heterogeneous airborne sensors as applied to construct and present accurate information to situation commanders. The SUAAVE project will adopt a practical engineering approach, building real prototypes in conjunction with an impressive list of external partners, including a government agency, the field's industry leaders, and two international collaborators.