Kirkland, WA, United States
Kirkland, WA, United States
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Grant
Agency: GTR | Branch: EPSRC | Program: | Phase: Research Grant | Award Amount: 3.77M | Year: 2013

The aim of this proposal is to transform the design and manufacture of structural systems by relieving the bottleneck caused by the current practice of restricting designs to a linear dynamic regime. Our ambition is to not only address the challenge of dealing with nonlinearity, but to unlock the huge potential which can be gained from exploiting its positive attributes. The outputs will be a suite of novel modelling and control techniques which can be used directly in the design processes for structural systems, which we will demonstrate on a series of industry based experimental demonstrators. These design tools will enable a transformation in the performance of engineering structural systems which are under rapidly increasing demands from technological, economic and environmental pressures. The performance of engineering structures and systems is governed by how well they behave in their operating environment. For a significant number of engineering sectors, such as wind power generation, automotive, medical robotics, aerospace and large civil infrastructure, dynamic effects dominate the operational regime. As a result, understanding structural dynamics is crucial for ensuring that we have safe, reliable and efficient structures. In fact, the related mathematical problems extend to other modelling problems encountered in other important research areas such as systems biology, physiological modelling and information technology. So what exactly is the problem we are seeking to address in this proposal? Typically, when the behaviour of an engineering system is linear, computer simulations can be used to make very accurate predictions of its dynamic behaviour. The concept of end-to-end simulation and virtual prototyping, verification and testing has become a key paradigm across many sectors. The problem with this simulation based approach is that it is built on implicit assumptions of repeatability and linearity. For example, many structural analysis methods are based on the concept of a frequency domain charaterisation, which assumes that response of the system can be characterised by linear superposition of the response to each frequency seperately. But, the response of nonlinear systems is known to display amplitude dependence, sensitivity to transient effects in the forcing, and potential bistability or multiplicity of outcome for the same input frequency. As a result, when the system is nonlinear (which is nearly always the case for a large number of important industrial problems) it is almost impossible to make dynamic predictions without introducing very limiting approximations and simplifications. For example, throughout recent history, there have been many examples of unwanted vibrations; Failure of the Tacoma Narrows bridge (1940); cable-deck coupled vibrations on the DongTing Lake Bridge (1999); human induced vibration on the Millennium Bridge (2000); NASA Helios failure (2003); Coupling between thrusters and natural frequencies of the flexible structure on the International Space Station (2009); Landing gear shimmy. In many cases, the complexity of modern designs has outstripped our ability to understand their dynamic behaviour in detail. Even with the benefit of high power computing, which has enabled engineers to carry out detailed simulations, interpreting results from these simulations is a fundamental bottleneck, and it would seem that our ability to match experimental results is not improving, due primarily to the combination of random and uncertain effects and the failure of the linear superposition approach. As a result a new type of structural dynamics, which fully embraces nonlinearity, is urgently needed to enable the most efficient design and manufacture of the next generation of engineering structures.


Grant
Agency: European Commission | Branch: FP7 | Program: CP-IP | Phase: AAT.2012.3.5-2. | Award Amount: 30.50M | Year: 2013

Outstanding safety level of air transport is partly due to the two pilots standard. However situations where difficult flight conditions, system failures or cockpit crew incapacitation lead to peak workload conditions.The amount of information and actions to process may then exceed the crew capacity. Systems alleviating crew workload would improve safety. ACROSS Advanced Cockpit for Reduction of StreSs and workload - will develop new applications and HMI in a cockpit concept for all crew duties from gate to gate. Human factors, safety and certification will drive this approach. The new system will balance the crew capacity and the demand on crew resource. ACROSS workload gains will be assessed by pilots and experts. A Crew Monitoring environment will monitor physiological and behavioural parameters to assess workload and stress levels of pilots. A new indicator will consolidate flight situation and aircraft status into an indicator of the need for crew resource. If this need becomes higher than available crew resource, cockpit applications and systems will adapt to the new situation : a) Decision support: cockpit interfaces will adapt to focus crew on needed actions, b) Prioritisation: non-critical applications/information will be muted in favor of critical elements, c) Progressive automation: crew actions not directly relevant with the situation will be automated, d) Decision sharing: in case of persistent crisis situation, an automatic information link with the ground will be established to further assist the crew. In extreme situation where both pilots are incapacitated, further steps will be: a) Full automation: measures to maintain the aircraft on a safe trajectory, then reroute to nearest airport and autoland. b) Decision handling: mechanisms allowing ground crew to remotely fly the aircraft. ACROSS groups a large team of key European stakeholders. They are committed to deliver innovation in the field of air transport safety.


Grant
Agency: European Commission | Branch: FP7 | Program: BSG-SME | Phase: SME-2012-1 | Award Amount: 1.05M | Year: 2013

This proposal will aim to develop the enabling technology that will enable existing pipe crawling robots (pigs) to provide internal inspection of pipe walls using long range ultrasound guided waves (LRUG) deployed in pipe segments of about fifty metre length. The aim is to perform total volume inspection far more rapidly, accurately and cheaply than is presently achieved with magnetic and ultrasonic pigs by developing a circumferential collar of LRUG sensors and novel time reversal focussing to produce a map of the circumferential and axial pipe corrosion and cracks. As LRUG sensors detect all significant corrosion in oil and gas pipelines within typically 50 metre of the sensors in a few milliseconds, long lengths of pipe can be scanned very rapidly with sample wave echo patterns obtained only every 50 metres thereby data storage requirements will be orders of magnitude less than present inspection methods. The speed of travel through the pipe could thus be faster than pigs that gather data with ultrasonic compression probes. To test the technology developed by the project, the LRUG collar will be deployed initially by a mechanism to pull the collar through a pipe full of water at different constant and also varying speeds. A prototype robot will be developed that is intrinsically safe for operation in explosive environments and that is lightweight (neutrally buoyant) to investigate how best to deploy the LRUG technology in a real pipeline with faster travel and cheaper robots.


Grant
Agency: European Commission | Branch: FP7 | Program: BSG-SME | Phase: SME-2013-1 | Award Amount: 1.31M | Year: 2014

The wind turbine industry is one of the fastest growing markets. Current turbines are huge with turbine rotor diameters of over 100m becoming standard. EU energy policy calls for 20% of the EUs 3040Th/y electricity demand to come from renewable sources by 2020, which constitutes a market of some 140 billion and wind energy is the clear front runner. Presently in situ blade inspection is carried out every 3-6 month visually or with manual operatives involved in dangerous abseiling. In certain cases, a blade is dismantled and transported onshore, making the turbine downtime very high. The AUTOWINDSPEC project will provide a system to automatically estimate the condition and remaining lifespan of the blades, by eliminating dangerous rope access and reducing downtime whilst increasing productivity. The inspection involves the following steps: - An autonomous robotic mechanism climbs automatically on the WT using already existing infrastructure. - Using novel Acousto-Ultrasonic NDE technique the condition of the blades is estimated. - The NDT equipment is applied through wheels to perform the inspection as a continuous process. - The coordinates and respective measurements are stored and through novel signal analysis techniques a map of the mechanical properties of the blades is produced pinpointing defects and estimating the remaining life of the entire blade. The AUTOWINDSPEC system aims for a target reduction of 84% in maintenance costs, since the inspection process will be completed in half time compared to current practice eliminating the need for trained operators. By including the reduction of revenue loss through increased downtime, overall savings can be greater. In addition, project SMEs will have enhanced access to the EU wind turbine maintenance market, set to reach 42 billion, i.e., 30% of renewable sources revenue by 2020.


Grant
Agency: European Commission | Branch: FP7 | Program: JTI-CS | Phase: JTI-CS-2010-5-GRA-02-014 | Award Amount: 450.38K | Year: 2012

A novel adaptive winglet concept will be developed to enable controlled cant angle orientation and twist throughout the flight envelope whilst also providing a passive gust loads alleviation capability. A CFD based aerodynamic design of the device applied on a baseline Turbo-Fan Aircraft configuration model will be undertaken, followed by a preliminary lay-out definition of the structure and actuation system required for the device. Detailed parametric studies will then be performed to investigate the performance of the device in terms of both drag and loads alleviation capabilities on its own, and also in combination with conventional control actuators, and both compared to the baseline configuration.


Grant
Agency: GTR | Branch: EPSRC | Program: | Phase: Fellowship | Award Amount: 946.06K | Year: 2015

Policy makers and regulatory bodies are demanding the aerospace industry reduces CO2 emission by 50% and NOx emission by 80% by 2020. In order to meet these drastic demands and ensure affordable air travel in the future, it is essential to make lighter aircraft which will use minimum fuel. The aerospace research community recognises the need to make a dramatic performance improvement and is considering several new aircraft concepts that move away from the conventional two-wing-one-fuselage configuration. This brings new challenges to aircraft design. A wing is a highly complex structure to design as it needs to consider the complex interaction between aerodynamics and structural behaviour. The current design practice is therefore very much based on using the previous successful design data. The challenge of departing from the conventional aircraft is that there are limited successful historical design data that is applicable to new concept aircraft. Once we have a wing design, however, there are sophisticated computational methods that analyse how the wing behaves under external flight conditions. In fact, there has been a significant level of development in computational analysis methods taking advantage of growing computational power. A prime example of this is the recent development in the computational modelling of materials. Using this technology, new advanced materials can be created in half the time that traditional material development takes and the return on investment in computational materials research has been estimated at between 300 - 900%. This fellowship is at the heart of developing sophisticated computational methods to design aircraft configurations that have not been considered before. The majority of the current methods analyse how a given material or structure responds to the external environment such as in flight at speed Mach 0.8, 38000 ft. What is different about the methods in this research is that they are inverse of the analysis methods: They will determine the best combination of advanced material and structural configuration based on the external environment and hence design the optimum wing for the given flight conditions. My research approach is to represent the design problem as a set of mathematical functions and develop computational methods to find the optimum solution. The methods will therefore, find the optimum design for both materials and structural configuration at the same time. The outcome of this fellowship will provide engineers with a sophisticated tool to design complex aircraft structures. The tools will be developed and disseminated in a way that they can be used on a range of other complex engineering problems. The UK has 17% of the global aerospace market share with revenue of £24 billion and is responsible for 3.6% national employment. With the international civil aerospace market forecast to grow to $4 trillion by 2030, the UK market has the opportunity to grow to $352 billion by 2030. It is critical that the UK develops this unique capability to ensure we maintain the market share of these high value products and processes and its economy has the opportunity for growth. Furthermore, the weight savings which will be made from optimum use of materials lead to meeting the emission targets, thus ensuring sustainable environment for the future generations.


Grant
Agency: European Commission | Branch: FP7 | Program: BSG-SME | Phase: SME-2012-1 | Award Amount: 1.42M | Year: 2012

Tidal stream power is a very environmentally attractive renewable energy source whose exploitation is being retarded by operation and maintenance problems which cause very low availability times, as poor as 25%. So the REMO project gaol is to provide an enabling technology for tidal stream energy, by reducing the projected life cycle maintenance costs of tidal stream energy by 50% and the generator downtime to a level comparable with wind turbines i.e. to achieve availability times 96%. This strategy will reduce present projected costs of tidal stream energy production down to levels comparable with life cycle wind turbine electricity costs (0.058/kWh) thus ensuring the economic viability of tidal generators. Energy providers will then be attracted to investing in tidal stream energy, so that its full economic potential and environmental advantages are realised. The REMO system will remotely and permanently monitor the entire frequency spectrum of structural vibrations generated by all the rotating components of a tidal stream turbine, by combining a suite of accelerometer and acoustic emission sensors for the low and high frequency regime respectively. The system will determine the vibrational signature of a healthy turbine and the evolution of that signature during the turbine life cycle. It will then discover any significant change in that signature that could be a symptom a structural health problem at any point in the life cycle, including the build up of marine fouling, and then issue an automatic warning. State of the art similarity analysis algorithms based on the Euclidian distance measure in multiple dimensions will be used in both the time and frequency domain for optimally cost effective processing of all vibrational data involved in the state of health diagnosis The system will be validated by installing it on an in-service tidal stream generator developed by one of the SMEs who will also be an end user of the proposed REMO technology.


Grant
Agency: GTR | Branch: Innovate UK | Program: | Phase: Smart - Proof of Concept | Award Amount: 82.97K | Year: 2013

Full Authority Submarine Control (FASC) is a new concept for submarine steering and diving systems, and combines Stirling’s proven Active Control Technology from the fly-by-wire aircraft industry with extensive experience in producing submarine autopilot and hover control software. This results in an integrated method of control which covers all steering and diving control requirements for the entire speed range of the submarine. Achieving this aim of bringing all the control surfaces together in a single system with full authority over the submarine will be a world first in operation. Stirling’s research into new concepts for submarine platform control has been prompted by a number of factors. Technology ‘push’ factors and industry ‘pull’ factors have now created an environment where the concept could be developed to become a viable production solution. Firstly, it was recognised that accepted issues with conventional methods of steering and diving control could be solved through the deployment of a cohesive control strategy. Secondly, future submarines will be required to operate in an increasing number of ever changing roles through the life of the submarine. Stirling’s customers are now placing requirements for more manoeuvres and operations to be performed under automatic control, in more challenging environments with performance criteria becoming more exacting and wide ranging. Performance requirements are being extended in the areas of setpoint following, disturbance rejection, and minimisation of control effort. Thirdly, there is an increasing desire to reduce through life costs which translate into requirements to minimise integration effort, manning, training and maintenance costs. All these have been combined in the system design approach for FASC. The project aims to develop a concept demonstrator that will enable the control strategy to be proven and provide a real-time environment for customer evaluation that will inform the next stage of development


Grant
Agency: GTR | Branch: EPSRC | Program: | Phase: Fellowship | Award Amount: 749.27K | Year: 2013

The dynamic behaviour of mechanical systems and structures is often critical to their performance. Examples where unpredicted dynamic behaviour has resulted in poor performance include the London Millennium Footbridge prior to retrofitting with dampers and wheel shimmy experienced in aircraft landing gear and motorbikes. When structures remain in their linear operating region, where the response is proportional to the size of the force causing it, there are well-established modelling and experimental validation tools for analysing their dynamic behaviour. If the structure exceeds the linear operating region and starts to exhibit nonlinear behaviour, for example due to large deflections, the effectiveness of these tools rapidly reduces leading to high degrees of design uncertainty. This uncertainty leads to multiple design iterations and increased costly experimental validation and even the discovery of undesirable behaviour late in the design process resulting in significant delay and additional expense. This presents a problem when trying to innovate to improve performance, for example by reducing weight or using new materials, as this tends to add nonlinear effects. Currently the consequence of the limitations in existing tools is that the resulting uncertainty is compensated for by conservative design. What are urgently needed are design tools that can cope with complex nonlinear behaviour. The new nonlinear design tools this research will provide will greatly reduced the costs associated with designing new high performance products. Such step changes to the UKs capability for advanced design will assist high-end manufacturing industry to maintain its competitive edge.


Grant
Agency: GTR | Branch: Innovate UK | Program: | Phase: Collaborative Research & Development | Award Amount: 940.38K | Year: 2014

Bonded composite patches are used to repair corrosion, fatigue and impact damage to airframes due to their superior mechanical integrity characteristics compared with mechanically fastened repairs. Such repairs also reduce aircraft down-time, maintenance labour costs and enable useful life extension. Success of a bonded repair is critically dependent on achieving suitable surface preparation and cure under difficult field conditions. Expanding the scope of patch repairs to primary load bearing structures, requires an added level of assurance where voids/disbonds are below a critical size threshold and that cure conditions result in adequate adhesive shear modulus without high residual stress. We propose to develop a smart-patch system with a reliable, low cost, integrated sensor network that will act as part of a feedback control system for active cure control to optimise both adhesive mechanical properties and minimise residual stress. The sensors will also be used as active transducer elements to enable non-destructive inspection of the patch to with a high probability of detection for voids and disbonds that are equal to or larger than the critical size.

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