Since 2012, students from the Innovation and Design Program (iDP) at NUS Engineering have been working to build a solar-powered quadcopter drone. Recently, former students Goh Chong Swee, Kuan Jun Ren, and Yeo Jun Han have succeeded in flying a prototype. Considered to be Asia’s first solar-powered quadcopter drone, it has flown to a height of ten meters and for two minutes.
The quadcopter drone is powered completely powered by solar energy—that means no need for batteries or even energy storage.
According to NUS Electrical and Computer Engineering Associate Professor Danner, battery-powered drones can typically sustain flight for about 30 minutes before needing to charge. A solar-powered drone, on the other hand, can potentially fly to faraway destinations and recharge itself during flight as long as there is sunlight. It can also operate autonomously without needing to be in range of an airbase.
“Our aircraft is extremely lightweight for its size, and it can fly as long as there is sunlight, even for hours. Unlike conventional quadcopter drones, our aircraft does not rely on on-board batteries and hence it is not limited by flight time. Its ability to land on any flat surface and fly high off the ground in a controlled way also makes it suitable for practical implementation,” said Danner, who supervised students under the iDP.
The team made refinements to earlier prototypes of the quadcopter drone by increasing the number of solar cells and adjusting the frame material to make it more efficient and lightweight. The first prototype back in 2012 was only able to achieve 45 percent of flight power from solar cells.
"We encountered many engineering challenges when building the drone," shared Mr. Yeo. "These included finding an optimal number of solar cells efficient and light enough to power the propulsion system, which in turn had to be light and at the same time able to produce sufficient thrust to lift the aircraft. Other issues we faced included tuning and calibration of flight controls to enhance flight stability, as well as designing a frame that is lightweight yet sufficiently rigid."
The team envisions the quadcopter drone to be potentially used as a "flying solar panel" to provide emergency solar power to disaster areas. It also has the potential to be used for photography, small package delivery, surveillance and inspection purposes. It is possible to add batteries to power the drone when there is no sunlight, or for charging. Hardware such as cameras could also be incorporated for other applications.
The team, jointly supervised by Teaching Assistant Brian Shohei Teo from iDP, was able to develop three prototypes in total over the two years spent on the project. They will continue to fine-tune the drone to improve its flight time and duration. At the moment, they are sourcing for better quality solar cells and studying how to reduce the size of the drone.
The team hopes to build a spin-off company in the future and bring the technology closer to commercialization in the future.
For more on the latest developments in drone technology, check out how these MIT engineering students are Designing Drones That Can Fly For Five Days Straight.