The RoboBee X-Wing is basically a flying machine that is almost half the size of the paperclip you can spot on office desks. The robotic insect can flap its wings 120 times in a second. According to a 2019 research paper published in the acclaimed journal ‘Nature’, a team of researchers at Harvard Microrobotics Laboratory in Cambridge claimed to have come up with what can be called as the ‘lightest insect-scale aerial vehicle’ that could sustain an untethered flight. The span of the untethered flight of the robotic insect is less than a second. Almost a centimetre in size, the machine was earlier called ‘RoboBee’. However, its name was upgraded to ‘RoboBee X-Wing’ after technological advancements made it possible for it to achieve an untethered flight.
The robot weighs 259mg. It can match the ‘thrust efficiency’ of insects like bees that are of the same size by using 110-120 milliwatt of power through solar energy. It works on the same principle as an aircraft, which is called the ‘heavier-than-air flight’. RoboBee X-Wing is heavier than the volume of air it displaced during the flight. That being said, applying the ‘heavier-than-air flight’ concept becomes more difficult as objects get smaller and lighter as is the case with RoboBee X-Wing.
Biologists for long have been interested in studying mechanisms used by insects to flap their wings and fly. Robotic insects that can flap their wings can help biologists decode the mysteries that still mar the theory of evolution of flight. These robots can also help experts find out more about environmental monitoring and natural selection. There is also another group of experts who are interested in these robots as they are looking forward to launching a new range of machines.
The current model of RoboBee X-Wing is too light to accommodate batteries as their weight would be more than the weight of the machine itself. This is why its makers chose to source the required power from solar energy sources directly. The vehicle sports solar cells attached to a rod that is installed above the four wings of the robot. The position would avoid any interruptions to the flow of air. To balance the centre of mass at the wings, the electronics have been installed directly opposite to the solar cells, right beneath the robot.
Even though RoboBee X-Wing resembles a dragonfly, it doesn’t have four wings like it. In its earlier avatars, each of RoboBee’s wings was powered by a motor or an actuator like an actual fly. However, while a dragonfly can use its wings independently, RoboBee X-Wing’s new wings are attached to the original ones. The reason why the makers fused the four wings was to increase the surface area of the attachments. With the doubled surface area of the wings, the fused attachments will boost efficiency by almost 30% and compensate for the extra weight of the additional electronics and solar cells.
During the testing phase, researchers had installed the lamps above the robot so that they could shine on the solar cells. Despite the strategic placement of the lamps, RoboBee X-Wing could manage a flight of less than a second. Hence, before the robot is let out in the wild, several improvements need to be made. The required changes include better solar cell technology and lighter and smaller batteries especially if the vehicle is expected to spend some time in the shade. That being said, these changes will only make the robots’ journey in the air more effectively and longer. The robot is currently not equipped enough to understand the world and other physical and atmospheric changes like the wind.
The robot features solar cells at the top and drive electronics at the bottom. The electronics help in the transmission of a voltage of up to 200 volts from the solar panels. The voltage is required to power the actuators which fuel the wings to flap at the rate of 200Hz. The current version of RoboBee X-Wing is likely to undergo some more changes as researchers are trying to reduce its power requirement to one sun or lower. The target requires the design to be optimized and some additional components to be integrated before the robot could attempt autonomous flights.
Another reason why these miniature robots have garnered so much attention is because of their potential to help in artificial pollination. Given the way the population of honeybees is suffering due to colony collapse disorder, these flying robots could save fields via artificial pollination. Their potential tasks also include helping in search operations in disaster zones and surveillance. A Ph.D. candidate at Harvard Microrobotics Laboratory, Elizabeth Helbling says that they are ideal for situations where bigger robots won’t fit in and can enable a faster relay of information. Researchers believe that these additions to the RoboBee X-Wing could take around five to 10 years to accomplish.