Research

Our research encompasses a wide range of activities across aerial robotics including:

  • unconventional sensing & actuation systems
  • trajectory optimization
  • machine learning flight control
  • multi-agent systems
  • unmanned traffic management
  • autonomous navigation & path planning
  • electrical systems optimization
  • morphing structures
  • trustworthy system design & operations
  • bio-inspired aerial vehicles

We also apply aerial robotics in a wide range of fields including volcanology, meteorology, agriculture, radiation monitoring, infrastructure inspection and endangered species tracking.

Some examples of our projects are listed below.

See our YouTube channel for more videos of some of our most recent research.

 

Birds and Turbulence

In collaborative work with the Royal Veterinary College, we have discovered that gliding birds fly smoothly because their wings act as a suspension system. Birds withstand sudden gusts by allowing their wings to pivot about the shoulder absorbing energy and leaving the head and body largely unaffected. The very fastest part of the suspension effect is built into the mechanics of the wings, so birds don’t actively need to do anything. The process is automatic and allows enough time for aerodynamic processes to start to work. Our next step is to use this new understanding to build better small-scale unmanned aircraft with improved performance in gusts and turbulence.

Drones and Volcanoes

The ABOVE project was an international endeavour, bringing together leading experts from Bristol with others across the world, all with previous hands-on experience of using aerial robotics to study volcanic emissions. Volcanic emissions are a critical stage of the Earth’s carbon cycle – the movement of carbon between land, atmosphere, and ocean – but CO2 measurements have so far been limited to a relatively small number of the world’s estimated 500 degassing volcanoes. Measurements need to be collected very close to active vents and, at hazardous volcanoes like Manam, drones are the only way to obtain samples safely.

Based on this expedition we published the following journal articles:

Have a look at the full ABOVE documentary too.

Atmospheric Sampling on Ascension Island Using Multirotor UAVs

In 2014 and 2015 we flew several UAVs in the Ascension Islands, the research outlined two highly successful field campaigns carried out on Ascension Island, collecting multiple atmospheric samples up to 2,700 metres above mean sea level using unmanned air vehicles (UAVs). This was the first time that such repeated, high-altitude air sampling missions have been carried out using lightweight drones. This low-cost method has been shown to be a highly flexible approach to atmospheric sciences which offers the potential to be highly automated and widely applied.

Based on this expedition we produced two journal articles:

Complex Autonomous Aircraft Systems Configuration Analysis & Design Exploratory

lots of drones

The Flight Lab is a partner in the EPSRC CASCADE Programme to accelerate the exploitation of aerial robotics across a wide range of science and industry applications. Through fundamental research and case studies, CASCADE is advancing the understanding and technologies required to allow routine operation of advanced aerial robotic systems. Flight Lab leads three case studies: volcanic plume sampling; inspecting a bridge; and high altitude meteorological data collection. CASCADE is led by the University of Southampton and also includes partners Imperial College, Cranfield University, and the University of Manchester. For more information please visit the CASCADE website.

SimSAC: Simulating Aircraft Stability & Control Characteristics in Conceptual Design

a340

Present trends in aircraft design towards augmented-stability and expanded flight envelopes call for an accurate description of the non-linear flight-dynamic behaviour of the aircraft in order to properly design the Flight Control System (FCS). Hence the need to increase the knowledge about stability and control (S&C) as early as possible in the aircraft development process in order to be ‘First-Time-Right’ with the FCS design architecture. FCS design usually starts near the end of the conceptual design phase when the configuration has been tentatively frozen and experimental data for predicted aerodynamic characteristics are available. Up to 80% of the cost of an aircraft is incurred during the conceptual design phase so mistakes must be avoided.

To meet these challenges SimSAC developed along two major axes: Creation and implementation of a simulation environment, CAESIOM, for conceptual design sizing and optimisation suitably knitted for low-to-high-fidelity S&C analysis; and an improved pragmatic mix of numerical tools benchmarked against experimental data. Check out the project on this EU website.

 Vision Based Autonomous Air-to-Air Refuelling 

Ascension

Air-to-air refuelling (AAR) is the process of transferring fuel from one aircraft to another during flight. Probe-and-drogue, one of the main systems for AAR, uses a flexible hose that trails from the tanker aircraft. At the end of the hose are a reception coupling, a drogue, and an aerodynamic canopy used to stabilise the coupling.

A rigid arm, called the probe, typically extends from the nose or fuselage of the receiver aircraft. Currently, the pilot of the receiver aircraft must manually adjust the aircraft position to engage the probe with the reception coupling so fuel can be transferred between the two aircraft. AAR can be a demanding procedure to perform because it requires advanced training and fast response times.

As part of the Autonomous Systems Technology Related Airborne Evaluation & Assessment (ASTRAEA) programme, researchers at the Bristol University Department of Aerospace Engineering collaborated with Cobham Mission Equipment to develop a safe and reliable hybrid test environment to accelerate the development of autonomous AAR technology for unmanned systems. This laboratory-based robotic test environment enabled the initial system development at a significantly lower cost than actual flight tests and help to minimize risk in hardware and software demonstration and certification.

The following papers explain this work in more detail

  1. Development of a relative motion facility for simulations of autonomous air to air refuelling
  2. A vision-based strategy for autonomous aerial refueling tasks
  3. Robotic Relative Motion Reproduction for Air to AirRefuelling Simulation
  4. Collaborative Control in a Flying-Boom Aerial Refueling Simulation

All of our previous research papers can be found under PI’s individual links.