RIE News May 2022 issue featured Associate Prof Foong Shaohui, see page 6 – 8, RIE News: https://www.nrf.gov.sg/docs/default-source/default-document-library/nrf-magazine/nrf-magazine-(may-2022)a.pdf
REINVENTING DRONES WITH INSPIRATIONS FROM NATURE
Dr Foong Shaohui and his team at SUTD harnessed the unique abilities of a winged seed into a pocket-sized drone design.
Imagine a drone that is so small in size that it can fit into one’s pocket, and can easily be launched by hand. This very first foldable, single wing drone design was in fact inspired by a seed, and was turned into reality by Dr Foong Shaohui and his team at Singapore University of Technology and Design (SUTD).
Dr Foong, an Associate Professor in the Engineering Product Development (EPD) pillar at SUTD, said, “Normally when we talk about developing and designing new aerial platforms, birds and insects would be a popular avenue for inspiration. But nature does have another avenue for flight, which come from trees.”
“Despite having no inherent locomotion ability, some species of trees have been able to spread and disseminate by developing winged seeds, such as the maple seed or samara seed. In Singapore, there is also the angsana seed, which gracefully glide to the ground in a rotary manner.”
This rotary motion, called autorotation, is a key mechanism which allows the seed to glide far from the tree when released at height.
It contributes to the seed’s enhanced stability as things that spins or rotates are usually are more stable, for instance it is easier to balance on a bicycle when its wheels are in rotation.
Rotation also enhances flight efficiency as it induces high speeds about the wings creating high lift, allowing it stay in the air longer.
Dr Foong and his team saw the potential in these unique abilities, and harnessed it in their design of the monocopter to feature the same benefits and advantages.
Key features of the monocopter
The nature-inspired monocopter can be summarised in four keywords – simple, efficient, scalable, and stable.
“The monocoptor comprises of just one actuator to achieve controlled flight, while others require a minimum of four,” shared Dr Foong.
“It uses wings for flight, allowing it to use less power to maintain flight to fly longer and further than popular multi-rotor unmanned aerial vehicles (UAV). This makes our design simple and much more efficient.”
He also explained that the monocopter can be grouped and combined like petals of a flower to operate as a unit and separate when required, bringing about scalability.
Its small and compact size, together with silent and lightweight features, also makes it fairly hard to detect and track in the air.
In the event of a loss of power, the monocopter would still gracefully descend to the ground just like a seed, when other drones would have crashed.
With these unique characteristics, Dr Foong shared that there has been interest to use these drones as a vehicle to carry and deploy sensors in remote areas in large numbers.
They are also versatile for usage from climate monitoring to military to disaster response at sites where it is difficult or dangerous for humans to access.
The team of scientists is now working on improving the flight characteristic and performance of the monocopter through mechanical design, electrical integration, new materials, and flight algorithms.
UAVs in everyday life
For Dr Foong, mobility usually deals with the ease of moving from one place to another, with the target being something tangible or physical like humans or packages.
But when it comes to moving information and data, he believes that is where UAVs or drones can excel.
“There are many tasks that are done every day that require humans to be subjected to danger,” said Dr Foong.
“As the UAV does not require a human pilot, it can reach these hard-to-reach places quicker, safer and cheaper, and hence, we will increasingly see a growing role of UAVs in our everyday lives.”