A breakthrough in the field of aviation has been achieved by a group of researchers from Beijing University of Aviation and Cosmonautics, led by Associate Professor Minjing Qi Chi. They have unveiled a groundbreaking aircraft that operates solely on solar energy. The newly developed drone, named COULOMBFLY, weighs a mere 4.21 grams, equivalent to the weight of a single sugar cube.
The standout feature of COULOMBFLY is its innovative electrostatic drive system. This system comprises a motor with a rotor and a stator, a 10-centimeter propeller, a high voltage converter, and solar elements. The engine’s stator is uniquely designed with eight pairs of alternating positive and negative electrodes arranged in a circular formation. Each electrode is equipped with a brush to facilitate the transfer of charge to the rotor blades.
By supplying a high permanent voltage, the electrostatic fields are generated, causing the rotor blades to transfer the charge as they pass by the alternating electrodes, resulting in rotation.
The team’s significant achievement was the successful flight of COULOMBFLY under natural sunlight conditions. This marks a crucial advancement in the development of micro-air vehicles (MAV) with extended flight durations. Currently available MAV devices can only stay airborne for approximately 10 minutes. As the size of drones utilizing batteries and electric motors diminishes, their efficiency decreases due to factors like friction.
The researchers believe that this development will greatly enhance the capabilities of MAVs, allowing for applications such as long-distance aerial reconnaissance.
Despite the remarkable progress, COULOMBFLY has certain limitations. The drone lacks a control system and relies on vertical guides for stabilization. Moreover, its operation is directly affected by the intensity of sunlight. To address these issues, engineers aim to develop a hybrid power system incorporating both solar elements and a battery.
Undeterred, the Minjing Qi team is already working on an even smaller prototype with a wingspan of just 8 millimeters, although this version can currently only fly on a tether.
The findings of this study have been published in the prestigious Nature scientific journal. Scientists highlight that their innovation paves the way for the creation of ultra-compact aircraft and could serve as an alternative to existing micro-drone designs. However, it is important to note the fragility of the drone due to its lightweight design.