Earth is a Noisy Planet. Human activity means that from megacities to oceans, most places are infected with noise and tranquility is disappearing. This was starkly illustrated during the Covid-19 pandemic lockdowns when transport and industry largely stopped, and we glimpsed what a better-sounding future might be. Noise is a health problem for one in five European citizens. At high levels it causes hearing loss. At moderate levels it creates chronic stress, annoyance, sleep disturbance and heart disease. Noise makes it harder to communicate, harming learning in schools and increasing withdrawal of older people from social situations. The 2023 House of Lord's Science and Technology Committee report called noise a "neglected pollutant" and recommended more research to reduce harms. Noise also increases mortality in marine and terrestrial wildlife. The CDT will go beyond noise control to research how to engineer positive sounds. From using sound to improve the accessibility of products, through to enhancing cultural events that boost well-being, there are many ways of creating a better aural future. The CDT focuses on the user need of businesses, society and government to create a more Sustainable Sound Future. In EPSRC's Tomorrow's Engineering Research Challenges, the sound of drones and environmental noise are highlighted as needing innovative solutions. This CDT will not only cover this challenge, but will also contribute to seven out of eight Tomorrow's Engineering Research Challenges, because noise and vibration cuts across many sectors such as transport, energy, environment, construction and manufacturing. Through the CDT, we will address recruitment issues faced by the UK's £4.6 billion acoustics industry. Our partners tell us they struggle to find doctoral-level graduates in acoustics. Cohort training will empower our CDT graduates with an unprecedented depth and breadth of knowledge. This is needed because of the complexity of the challenge, from re-engineering machines, systems and buildings, through to understanding how sound affects the health and well-being of humans and other animals. Current PhD training in acoustics is too piecemeal to tackle a problem that cuts across sectors, regulators and society. The CDT will create a unique cohort of future research leaders and innovators, with the ability to create a step-change in how sound is tackled working across disciplines. This CDT brings together four powerhouses in acoustics: the Universities of Salford, Bristol, Sheffield and Southampton; along with industrial partners, regulatory bodies, public and third sector. This provides CDT students with access to an extraordinary range of laboratories and breadth of expertise for their training. This includes domain and application knowledge across many disciplines; state-of-the-art simulation, measurement and auralisation capabilities; datasets and case studies, and routes to impact. The CDT builds on EPSRC's UK Acoustics Network that has over 1,700 members including 500+ early career researchers. Challenging interdisciplinary research projects and cohort-based training will develop the much-needed postgraduates. A mixture of week-long residentials, group project and online activities are planned. These will develop technical skills for acoustics (simulation, measurement, machine learning, psychoacoustics, etc. and key skills for research (project planning, entrepreneurship, public engagement, policy influencing, responsible innovation, etc.). Partner placements will play an important role in ensuring the cohort learns about context and how to create impact. The learning outcomes of the training have been co-created between academics and partners, to ensure CDT graduates have the skills, knowledge and understanding to create a more sustainable sound future for all.

Lasers are a key enabling technology in countless areas of modern society, touching on our lives in terms of ubiquitous connectivity, data storage, healthcare, security, environmental monitoring, etc. Examples include telecommunications, where they are used to generate the information carrying optical signals that are transmitted along thin glass optical fibres, manufacturing, where they are used for welding and cutting materials, and medicine, where they are used for sensing blood oxygen levels, and precisely resecting tissues. For almost all laser applications, it is necessary to use the laser source in combination with another technology that directs or "steers" the laser light in the desired direction. In some cases, this technology can be "passive", as is the case with the glass optical fibres used in telecommunications. In other cases, the steering technology must be "active" to change the direction of the laser beam in time, as is the case with the rapidly moving mirror systems used in some laser cutting and laser imaging systems. Conventional active laser steering technologies are often costly, bulky, and fragile. One or more of these disadvantages makes them sub-optimal for many important applications, including laser imaging systems for automotive applications, space-based laser communications systems, and drone-based remote sensing systems. To address this, there is currently a global drive to develop fully integrated solid-state beam-steering technologies, where the laser light is steered without the use of any physically moving components. Currently, however, even state-of-the-art solid-state laser beam steering systems have limited functionality, and do not meet the requirements of many real-world applications. In this project, we will exploit recent advances in two key integrated optical technologies - coherent Photonic Crystal Surface Emitting Laser (PCSEL) diode arrays and three-dimensional optical waveguide devices known as "integrated photonic lanterns" - to develop fully Integrated Solid-State Steerable Lasers (I-STEER) that can deliver agile beam steering in two dimensions and can, in principle, function at any diode laser wavelength. I-STEER will target the development of 900-mode PCSEL arrays, but will deliver the technological advances necessary to enable future PCSEL arrays (using commercial manufacturing facilities) that generate 10's of thousands of independently phase and ampltiude controllable coherent laser modes. A key aim of I-STEER is to enable denser PCSEL arrays, where the laser mode diameter is reduced to 20 microns (~20 wavelengths) and the centre-to-centre separation is reduced to ~50 microns (~50 wavelengths) - current PCSEL arrays exhibit 50 micron diameter laser modes with centre-to-centre separations of 400 microns. Unfortunately, even the ambitious spatial scales we are targeting mean that the PCSEL array will still be unsuitable for direct use as an optical phased array (OPA), since OPAs require very tightly packed wide angle emitters to achieve large angle/lobe free beam-steering. To address this, I-STEER introduces the fresh idea of using three-dimensional integrated optical waveguide transitions known as "integrated photonic lanterns" to adiabatically combine the PCSEL modes into a single highly multimode pattern of light, the spatial phase and amplitude properties of which can be directly controlled for beam steering via the PCSEL drive electronics. Through the I-STEER project, we aim to redefine the laser diode as an all-electronic integrated steerable light source enabling new functionally in countless applications including free-space optical communications and LiDAR. The generation of intellectual property and capability in this area will place the UK in a leading position with regards this strongly growing academic field, wealth generation through the creation of licensing and/or spin-outs, and in early adoption of UK based OEMs of this new technology.

The sensing, processing and transport of information is at the heart of modern life, as can be seen from the ubiquity of smart-phone usage on any street. From our interactions with the people who design, build and use the systems that make this possible, we have created a programme to make possible the first data interconnects, switches and sensors that use lasers monolithically integrated on silicon, offering the potential to transform Information and Communication Technology (ICT) by changing fundamentally the way in which data is sensed, transferred between and processed on silicon chips. The work builds on our demonstration of the first successful telecommunications wavelength lasers directly integrated on silicon substrates. The QUDOS Programme will enable the monolithic integration of all required optical functions on silicon and will have a similar transformative effect on ICT to that which the creation of silicon integrated electronic circuits had on electronics. This will come about through removing the need to assemble individual components, enabling vastly increased scale and functionality at greatly reduced cost.

For high technology companies such as Leonardo engaging in innovative research that might not produce a commercial return on investment for up to 10 years or beyond is vital. Our vision is to enable a paradigm shift in high-value low-volume remote sensing systems from concept to production: this requires a fusion of computational imaging concepts, that blur the traditional boundaries between sensing and signal processing, through-life digital modelling, that places innovative manufacture at the heart of the total system design and finally, individual AI/Robotic support, that multiplies the output of highly skilled production and maintenance personnel. The low volume, highly complex sensor systems produced by Leonardo present complex engineering challenges for design and production. Advances in machine learning, cobotics, novel materials, additive manufacturing, digital twinning and signal & image processing provide new paradigms for the end-to-end design and production processes and requires the development of a fully integrated digital design, assembly and manufacturing capability.

The UK composites industry faces an imperative to prioritise sustainability. The urgent need to reduce impact on the environment and ensure the availability of resources for future generations is critical to securing a prosperous and resilient future. Composite materials are crucial for delivering a Net-Zero future but pose several unique technical challenges. Sustainable Composites Engineering defines a holistic means of achieving environmental neutrality for composite products through production, service, and reuse. It incorporates the pursuit of more sustainable composite materials, with a mission of creating inherently sustainable composite solutions, able to perform in diverse environments, and made using new scientific advances, and new energy efficient, waste-free manufacturing procedures. Our proposed CDT in Innovation for Sustainable Composites Engineering will address the challenges by developing a workforce equipped with the skills to become leaders in the future sustainable economy and support UK industry competitiveness. Our CDT is jointly created by the Bristol Composites Institute, the University of Nottingham and the National Composites Centre (NCC). In addition to the EPSRC funding our CDT is also supported by industry and we have received 27 letters of support from companies in the UK Composites sector: Aerospace (Airbus, Rolls-Royce, Dowty, Leonardo, GKN), Defence (QinetiQ, AWE, BAE Systems), Automotive (Gordan Murray, JLR), Wind Energy (Vestas, EDF-Renewables), Marine (Tods), Rail (Network Rail), Oil and Gas (Magma Global), Hydrogen (Luxfer) alongside material suppliers (Hexcel, Solvay, iCOMAT, SHD), and specialist design and manufacturing companies (Pentaxia, Actuation Lab, LMAT, Molydyn), as well as RTOs (NPL, NCC). The total industrial commitment to our CDT is >£10M, with>£4M from NCC. From this it is clear that our CDT fits the Focus Area of Meeting a User Need. The CDT will provide a science-based framework for innovative, curiosity driven research and skills development to facilitate composites as the underpinning technology for a sustainable future. Critically, the CDT will offer an agile doctoral educational environment focused on advanced competencies and skills, tailored to industrial and commercial needs, providing academic excellence and encourage innovation. The ambitious goal of spanning Technology Readiness Levels (TRL 1-4) will be achieved by having a mix of university-based PhDs and industrially-based EngDs . Fundamental industrial sponsored research will be carried out by PhD students based at the Universities. The EngD students will spend 75% of their time in industry conducting a research project that is defined industry. Students will complete their doctoral studies in four years, the doctoral research will run concurrently with the taught component, so students are immersed in the research environment from the outset. The bespoke training programme demands the critical mass of a cohort. A specific role on our Management Board focuses on maximising cohort benefits to students. The cohort continuity across years will be ensured by a peer-to-peer mentoring programme, with all new students assigned a student mentor to support their studies, thereby creating an inclusive environment to provide students with a sense of place and ownership. Methods for developing and maintaining a cohort across multiple sites will be supported by our previous experience with the IDCs strategy and by: -A first year based in Bristol with students co-located to encourage interaction. -In-person workshops in year 2 credit bearing units and professional activities. -Peer-to-peer individual mentoring, as well as in DBT and credit-bearing workshops. -Annual welcome cohort integration event. -Annual conference and student-led networking. -Internal themed research seminars and group meetings -Student-led training and outreach activities.