One aspect of farming that most people never think of is the agricultural waste left behind after a crop is harvested. The stems, stalks, and leaves that aren’t used for consumption need to be discarded somehow. Some farmers will sell this agricultural waste to livestock farmers for feed. Others will make giant compost piles, recycling the waste into a nutritious soil supplement. Many others simply burn agricultural waste, which can lead to air pollution. Such is the case for pineapple farmers in Malaysia. The leaves left after harvesting pineapples are too tough and fibrous to be recycled into animal feed or compost. A team of researchers from Putra University in Malaysia has found a way of recycling pineapple leaves to make drones.
Founded in 1971, Putra University is one of the leading universities in Malaysia and is best known for its programs in agricultural sciences. Malaysia is the largest supplier of palm oil in the world, and much of the country relies on internal farming for survival, which is why the study of agriculture is so important in Malaysia. Professor Mohamed Thariq Bin Hameed Sultan from the university’s Department of Engineering leads the waste-reducing research project, a project that is linked in with agricultural studies. As part of his research, he figured out a way to render the leaves of pineapple plants into a bio-composite that can be used to build the frame of a drone.
The discarded leaves are fed into a machine that is almost like a paper shredder. What is left of the leaves is a bucket full of pulp and the skeleton of the leaf that can now easily biodegrade. Professor Sultan consulted with Mr. William Robert Alvisse of the Malaysian Unmanned Drones Activist Society as to how to take the pineapple remains and turn them into a drone. The pulp is pressed into a hard sheet and then cut to fit the required shape of a drone’s body. Mr. Alvisse then attaches the pineapple body parts to the electrical components and rotors. The resulting product is a small drone, a bit bigger than the palm of your hand, that can reach altitudes of 1,000 meters with an average flight time of 20 minutes.
In terms of size and flight, the pineapple drone is similar to the DJI Mavic Mini. The Mavic Mini is one of the most popular drones on the market because of its high quality and low price. However, the pineapple drone costs a fraction of the price to make compared to the Mavic. Not only is it less expensive, but according to Professor Sultan, the pineapple materials have a higher strength to weight ratio and are still lighter than synthetic materials used in standard drone construction. Because the drone’s body is made from a processed bio-composite it can now be easily recycled. If the drone crashes or becomes damaged, the body is separated from all the electrical components and can be buried in the ground. Within two weeks, the processed pineapple leaves will degrade.
The next step in Professor Sultan’s pineapple drone project is to build one that is larger and can support additional payloads like cameras. A drone constructed with recycled agricultural waste that has the same performance ability as standard drones could have a massive impact on sustainability. Being inexpensive and easily replaced, such a drone could be widely used in military operations where drones are often disposable. An inexpensive drone can also become of great use to farmers who are struggling in the current economy.
Agricultural drones are one of the fastest growing drone markets. However, many small farmers still cannot afford them. But as Malaysian pineapple farmer Irwan Ismail said, a drone made from his discarded pineapple leaves is not only affordable but can help him increase his revenue. “For example,” he said, “three acres of this land may be able to produce 5 or 10 tonnes of this waste. And, imagine for example that the price is 5 or 6 Ringgit Malaysia per kilogram. If you multiply that by 5 to 10 tonnes it will have a big financial impact on the community, especially on small farming groups.” Researchers are always looking for ways to sustainably advance technology. Professor Sultan hopes that his waste-reducing pineapple drone encourages others to create similar sustainable devices.