.The University of Sydney’s Australian Centre for Field Robotics (ACFR) is exploring a potential use of flocks of cooperating gliders as the basis for a surveillance system that would autonomously detect and catch thermals to provide extended endurance.
An initial glider prototype, derived from a model aeroplane, is now in the process of being converted into a UAV and is expected to fly in six months. Basic results on the feasibility of the concept are anticipated by the end of this year following initial flight activity.
Dr Salah Sukkarieh, associate professor at the University of Sydney, says: “The objective is not just to catch thermals but we want to do a mission. So for example it might be environmental monitoring or tracking, but how do you do that with the added constraint that you have to be at certain locations, in other words catching thermals, to maintain endurance at the same time?”
Speaking at the Association for Unmanned Vehicle Systems International’s (AUVSI) Unmanned Systems Asia Pacific conference in Melbourne, Australia, Sukkarieh said that the cooperative UAV approach was necessitated by the potential weight of a single platform approach: “Cooperative gliders really come down to the fact that if you are trying to sense thermals then the sensor packages become very heavy. If you want to keep it small then maybe one option is the ability for gliders to cooperate and inform each other about where thermals are, so you get this constant pattern of team sharing.”
At its simplest the thermal detection system could “use variometers that gliders normally use now or accelerometers on the [autopilot] inertial measurement unit to sense where the thermal is”.
However, more complex systems are possible. “There are other sensors that we are currently looking at the feasibility of, such as little radar packages that look at dust particles that get caught up in the air. There are groups in Europe that are looking at vision cameras that try and spot where eagles are catching thermals, which might not work at all times.
“The simplest approach is just the self awareness, so how do I sense an uplift? And if I have it I must be in a thermal and bank left or bank right. The more complex is trying to sense thermal patterns or dust particles in the air.”
The planned flight trials campaign will occur at ACFR’s range at Marulan, located halfway between Canberra and Sydney. “By the end of this year hopefully we will have something”, Sukkarieh says.
Source: FlightGlobal.com