Imagine a tiny drone equipped with a camera, powered entirely by sunlight. These drones can be configured to fly in formations resembling flocks of birds, swarms of bees, or rows of ducks. Designed for large-scale applications, they are capable of conducting surveys to prevent landslides over vast areas or managing precision agriculture tasks. From measuring soil moisture across several hectares to diagnosing crop diseases, determining where water or pesticides are needed—these drones can handle it all.
Leading the innovation behind the world’s smallest solar-powered drone is Dr. Hasan Shahid, a Bangladeshi researcher and academic. A Reader (Associate Professor) at the School of Engineering and Materials Science, Queen Mary University of London, Dr. Shahid hails from Hanuya village in Bakerganj, Barishal. After completing his education at Barishal Cadet College and Dhaka University, he earned a PhD in Robotics from the University of Sheffield under a Commonwealth Scholarship.
In addition to his groundbreaking research, Dr. Shahid has made remarkable contributions to higher education. He is the first Bangladeshi academic to receive the UK’s prestigious National Teaching Fellowship (NTF) award, recognizing excellence in university-level teaching.
In an engaging conversation with DigiBanglaTech Executive Editor Imdadul Haque, Dr. Hasan Shahid shares insights into his research, innovations, and aspirations.
Question: You were in a cadet college, where strict discipline is a hallmark. How did you develop an interest in robotics amidst such a regimented environment?
Answer: The rules and discipline of cadet college help cadets become balanced individuals; they do not restrict one’s curiosity or enthusiasm. My interest in science was sparked in grade seven when our teachers would share fascinating anecdotes about science and scientists in our science classes. I vividly remember a teacher once asked, “What do you want to be in the future?” and I replied, “I want to be a scientist.” At that time, however, I did not know what kind of scientist I wanted to be. My interest in robotics came later when I was studying Applied Physics and Electronics at Dhaka University. Our professors would often talk about robots, and we learned that some of them were pursuing PhDs in robotics abroad. This inspired me to pursue research in robotics. Eventually, I completed my PhD in robotics from the University of Sheffield under a Commonwealth Scholarship.
Question: Could you provide an update on your ongoing research?
Answer: I have authored over 100 research papers. To date, 15 students from Bangladesh and other countries have completed their PhDs under my supervision, and currently, five more, including a professor from Dhaka University, are conducting PhD research under my guidance. Beyond the solar drones, I am working on several other projects, including capsule robots for inspecting the human gastrointestinal system and diagnosing diseases, prosthetic hands with sensory capabilities, and robots designed to assist the elderly and disabled.
Question: What inspired you to develop the SolarCopter?
Answer: While at Sheffield, one of my close friends was researching helicopters. After submitting my PhD thesis, I had some time before my viva, so I joined him in his helicopter research. Together, we published two joint research papers. After joining Queen Mary University as a faculty member, I started researching both robotics and helicopters. A version of the helicopter is the quadrotor drone, which is essentially a part of robotics and referred to as aerial robots. Quadrotor drones with cameras are very popular for capturing videos, so I began researching them. However, these drones face a major limitation: their batteries drain quickly, reducing their flight time. Adding more batteries increases the weight, which makes it harder for them to fly. To address this issue, I began working on solar-powered drones.
Question: Despite having four propellers, you refer to it as a multirotor rather than a quadrotor. Why is that?
Answer: Quadcopters, hexacopters, and similar drones are broadly classified as multirotors in comparison to single-rotor systems. However, one could also refer to them as quadcopters or quadrotors if they wish.
Question: Robots and drones are garnering significant attention. Your focus, however, is on productive uses of drones rather than military applications. How did this vision take shape?
Answer: The drones we are developing have vast potential for productive applications. Personally, I am very interested in their civilian uses. These drones will only begin to serve humanity once production starts. For now, however, I prefer to dedicate my time to research. In addition to the SolarCopter, I am working on several other important projects that I aim to advance further.
Question: Does the SolarCopter have a specific name?
Answer: The current drone is a result of our continued research on the SolarCopter, so we have retained the name “SolarCopter.” This particular drone is referred to as the “Micro SolarCopter.” It does not have a separate name yet.
Question: How long can the drone fly using only solar power?
Answer: The drone is equipped with a lithium-polymer battery, which is charged by the solar panel. The integrated solar panel extends its flight time by about 10 to 12 percent. Charging the battery takes about 6–8 hours. Currently, the system can fly up to 15 meters in height. In the videos, you can see it being flown in different directions, but the range has not been specifically measured. We have used a standard solar cell, but it has been divided into three parts using a laser cutter. These three parts collectively amount to approximately half the area of a regular solar cell.
Question: Is it possible to operate the solar drone without batteries, using only solar energy?
Answer: In 2013, we successfully flew a SolarCopter using 36 cells without any battery or low-energy storage, proving that a quadrotor system could be powered purely by solar energy—albeit for a short duration. With more solar cells, it is possible to operate quadrotor systems purely on solar energy. However, with the current technology, it is not feasible to power such a small multirotor system solely on solar energy. In the future, as the efficiency of solar cells improves, such systems may become viable. Our efforts in this direction continue.
Question: Can your drone operate in the dark?
Answer: Yes, it can. The drone is equipped with a lithium-polymer battery, which is charged during the day using solar energy. The charged battery can power the drone at night.
Question: The SolarCopter was invented in 2012. Now, in 2024, how far has the innovation progressed? Where do you see the use of drones in the next decade?
Answer: My previous answers may have hinted at some of the progress made. The SolarCopter has evolved from the one-meter-sized multirotor drone of 2012 to this much smaller multirotor drone. The use of drones is growing at an unstoppable pace, especially in civilian applications. Our focus and research are exclusively on civilian uses of solar drones. From monitoring construction sites to observing wildlife in forests, assessing risks during disasters, tracking weather patterns, managing traffic, and supporting relief operations during floods or earthquakes, drones will continue to find more applications.
My research on drones is ongoing. Apart from improving multirotor drones, our future plan is to develop a solar quad plane that is less than 25 kilograms in weight. It will fly at low altitudes like a helicopter and perform vertical take-off and landing without the need for a runway. Such a system has immense potential for applications like data collection, inspection, surveillance, and even transporting lightweight yet critical items, such as essential medicines.
Question: Could you share a memorable or challenging experience with drones?
Answer: In 2014, I was featured in a news segment on a Bangladeshi TV channel for my SolarCopter. My family was in Bangladesh at the time. I received a call from home, and on the other end was the voice of a little girl, saying, “Daddy, you made the SolarCopter. I saw you.” It was my seven-year-old daughter. Her words still echo in my mind from time to time.
DigiBangla: Thank you for taking the time to answer these questions.
Hasan Shahid: Thank you, and my love and gratitude to everyone who has been patient enough to read through this.
