When it comes to flight, nothing beats nature’s designs of birds and flying insects, whose efficiency is unmatched. Engineers often take inspiration from nature when developing robots to improve particular dynamics, and the researchers from the University of Bristol have looked to bees and other flying insects to create their latest robots.
Over the years, drones inspired by birds and insects have achieved stable, efficient flight but haven’t cracked the nuance of maneuverability. Some animals can change direction on a dime while flying — look at bees and fruit flies, and you get the idea. The engineering team at Bristol built their insect robots to mimic those flight characteristics without using complex transmission systems that use gears and motors. Instead, the team designed what they term as a “Liquid-amplified Zipping Actuator” (LAZA), which uses a direct-drive artificial muscle system to beat its wings and gain increased maneuverability.
The robots’ wings were designed using a series of electrodes, with one sticking out between a pair of others at the base. To get the artificial wings to flap, a high voltage is sent through each base electrode in an alternating pattern, attracting the wing electrode to each one in turn. When done fast enough, it produces a flapping motion, which is amplified by a liquid dielectric between the electrodes.
The LAZA system allows users to finely control the frequency and amplitude of the flapping wings, which can provide more power than their biological counterpoints of the same size. During testing, the robot could fly across a room at about 2.5 km/h (1.6 mph), or 18 body lengths per second. Moreover, Its wings lasted over a million cycles with no performance degradation, demonstrating that it should be able to fly long distances.