Field Demonstration of a Two-Stage Rotary-Nozzle Dispenser for Aerial Shrimp Feeding

In the quiet, sun-drenched waters of a shrimp farm, the most critical task is also the most difficult to get right: getting food to the animals. Shrimp do not graze like cattle; they wait for feed to arrive, and if it arrives in one spot or at the wrong time, the results are costly. Uneaten food rots, fouling the water and stressing the animals, while missed meals stunt their growth. For decades, farmers have relied on fixed machines along the pond's edge or manual throwing from boats, but these methods struggle to cover the vast, open surface of a modern pond evenly. The challenge is not just to drop food into the water, but to scatter it widely and consistently from a single point, fighting against the wind and the physics of falling pellets.

This is where the idea of using a flying drone enters the picture. A drone can hover over any part of a pond, theoretically solving the problem of coverage. However, simply attaching a bucket of food to a drone and letting it fall is not enough. The wind can blow the light pellets far off course, and the spinning propellers of the drone create a downward rush of air that can scatter the food unpredictably. The real engineering puzzle is how to move the food from a storage container inside the drone to an exit point, and then how to spin that exit point to spread the food out, all while the drone is vibrating and moving through the air.

A team of researchers from the Islands Development Company in Seychelles and Angarud Aerobotics in India set out to test a specific mechanical solution to this problem. They built a prototype drone and a special feeding device to see if the mechanics could work in the real world, specifically over a commercial shrimp farm on the island of Coëtivy. Their goal was not to prove that this method would immediately save money or grow bigger shrimp, but to answer a simpler, more fundamental question: could a drone successfully carry a small amount of feed, move it through a machine inside the aircraft, and spin a nozzle to release it into the water without the machine jamming or failing?

The researchers constructed a small, six-rotor drone, a type often used for photography and inspection, and attached a custom-built feeder underneath it. The feeder was designed with two distinct parts that worked independently. The first part was a small, motorized pusher that acted like a gentle hand, moving the shrimp feed pellets from a stationary storage hopper down into a lower chamber. The second part was a rotating turret at the very bottom, holding two nozzles facing opposite directions. This design was clever because it meant the heavy storage bucket did not have to spin; only the small exit nozzles rotated. This separation allowed the drone to carry the feed steadily while the nozzles spun to throw the pellets out in a wide arc.

To test this, the team loaded the drone with approximately half a kilogram of shrimp feed. They then flew the drone manually over a large, rectangular shrimp pond. The weather on the day of the trials was not perfectly calm; the wind was blowing between 4.0 and 6.7 meters per second, which is a moderate breeze. Despite the wind and the vibration of the drone's motors, the team successfully completed three separate flights. In every trial, the drone took off, flew over the water, and the internal pusher successfully moved the feed into the lower chamber. Then, the rotating turret spun, and the two nozzles released the pellets into the air below the drone. The machine did not jam, the feed did not get stuck, and the pellets fell out as intended.

The success of these three flights was a significant step forward, but the researchers were very careful about what they claimed. They demonstrated that the mechanical chain worked: the drone could carry the load, the pusher could move the food, and the spinning nozzles could release it. However, they explicitly stated that they did not measure how well the food was distributed. They did not know if the pellets landed in a perfect circle, how many broke apart when they hit the water, or exactly how much wind pushed them off course. They also did not test if the drone could fly long enough to feed a whole farm, as the half-kilogram load was far too small for a real commercial operation.

The paper goes on to outline what a full-scale version of this system would need to look like, separating the proven facts from the future plans. The researchers propose that a future drone would need to carry 25 kilograms of feed per trip, requiring a much larger and more powerful aircraft than the one they tested. They describe a vision for a complete farm service where the drone lands at a special dock to automatically refill its feed from a large silo and recharge its battery. This future system would also include a more advanced feeder with three adjustable nozzles that could change their angle to fight the wind, a feature the small prototype did not have.

The authors are clear that these larger, more complex ideas are currently just designs and calculations, not tested reality. They have calculated that a drone carrying 25 kilograms would need a very large storage space and a powerful battery to complete its tasks. They have also mapped out a detailed plan for how the drone would fly to different points in the pond, wait for the wind to be right, and release the food. But until a machine built to these larger specifications is tested, these remain proposals. The current study proves that the basic idea of a drone with a spinning feeder can work, but it leaves the hard work of making it efficient, accurate, and commercially viable for the next stage of research.

Ultimately, this work is a proof of concept. It shows that the mechanical heart of an aerial shrimp feeder can beat in the real world, even with wind and vibration. The team has shown that you can separate the job of moving the food from the job of spinning the feeder, and that this separation works on a flying machine. While the path to a fully automated, wind-compensating, 25-kilogram delivery system is still long and requires many more tests, this study provides the first concrete evidence that the machinery can function as intended. It turns a theoretical idea into a working machine, setting the stage for the future experiments needed to turn this flying feeder into a standard tool for shrimp farmers.