Scientists Build The Smallest, Lightest Solar-Powered Drone

In the last few decades innovations in the world of drones have hit high speeds.

Apart from being commercially available for personal use, these electrically powered unmanned aircraft systems can also enhance agriculture, delivery, logistics, inspection, construction, emergency services, search and rescue, entertainment and more. All this with the vehicle's flight controls being remotely controlled.

Furthermore, they also offer great applicability in discrete aerial reconnaissance and surveillance of hostile regions. This is one of the main reasons many companies strive to reduce the size of such drones and produce strong and capable micro aerial vehicles or micro air vehicles (MAVs).

Unfortunately, developing MAVs comes with many challenges, including flight time, load capacity and other issues.

However, scientists and researchers from the Beijing-based Beihang University have come up with a solution that beats numerous troubles.

So, what challenges did the researchers solve? Let’s explore!
 

What Challenges Does Beihang University’s CoulombFly Address?

 

• In a paper published on Nature, the world's leading multidisciplinary science journal, scientists and researchers from the Beihang University in Beijing, China, announced that they designed a drone that can overcome various challenges in current MAVs.

• These challenges include limited flight duration, which are mainly found in ultralightweight MAVs weighing less than 10g.

• Furthermore, such aircraft that weigh under 10 grams typically offer a flight endurance of around 10 minutes.

• Developers have even experimented with other propulsion systems; however, the added weight of these systems reduces the MAV’s ability to fly freely.

• While solar power proves to be a useful alternative for MAV’s, none have been able to achieve untethered sustained flight in natural sunlight.

• That is until the research team from Beihang University unveiled their new prototype – CoulombFly.

 

What Is Beihang University’s CoulombFly About?

 

• Weighing just 4.21 grams with a wingspan of 20 centimeters, CoulombFly is around 10 times smaller and 600 times lighter than the previous smallest sunlight-powered aircraft, which is a quadcopter that weighs 2.6 kilograms and is 2 meters wide.

• Essentially, the CoulombFly MAV is said to be the smallest and lightest solar-powered aerial drone that weighs less than a nickel and can fit in the palm of a person’s hand.

• CoulombFly is also the first solar powered MAV that can achieve sustained flight, meaning that it can keep flying as long as it receives sunlight.

• Ordinarily such MAVs use electromagnetic motors, which witness relatively greater friction generation in smaller motors as compared to bigger ones, as well as energy loss from electrical resistance.

• Additionally, as the vehicles get smaller, the surface area for sunlight collection also reduces.

• Here, CoulombFly uses an electrostatic motor, which leverages electrostatic fields to generate motion. This motor weighs only 1.52 grams and offers two to three times more lift-to-power efficiency.

• The motor consists of two rings, one inside and one outside. The inner ring has 64 slats made of carbon fiber sheets covered in aluminum foil and resembles a curved fence.

• The outer ring is made of 16 positive and negative electrode plates made of carbon fiber bonded to aluminum foil, with brushes touching the inner ring slats.

• As sunlight touches the outer ring’s plates, it produces electric fields as the brushes touch the inner ring and electrically charges the slats.

• In a test flight under natural sunlight conditions, CoulombFly achieved takeoff in one second and remained unaffected in flight for an hour.

• Nature’s YouTube handle also posted a video about CoulombFly.

 

What Did Mingjing Qi Say?

 

• Mingjing Qi, a professor of energy and power engineering at Beihang University in Beijing, said, “The operating current is extremely low for the same power output, resulting in almost no heat being generated by the motor. The high efficiency and low power consumption of the motor allow us to power the vehicle with a very small solar panel.”

• [Contd.] “We have managed to get a micro-aerial vehicle to fly using natural sunlight for the first time. Before this, only very large, ultralight aircraft could achieve this.”

• Qi added, “My ultimate goal is to make a super tiny flying vehicle, about the size and weight of a mosquito, with a wingspan under 1 centimeter.”

• ”Right now, there’s still a lot of room to improve things like motors, propellers, and circuits, so we think we can get the extra payload up to 4 grams in the future. If we need even more payload, we could switch to quadcopters or fixed-wing designs, which can carry up to 30 grams.”

• Speaking about the future, the research team plans “to use this propulsion system in different types of flying vehicles, like fixed-wing and rotorcraft.”

Do you think the CoulombFly MAV prototype will help propel the drone, robotics and surveillance industry to new heights?

Let us know in the comments below!