Controlling Flight Of Insect-Sized Robots

Researchers solved the problem of simulating bug-like flight for microbots by replacing gyroscopes with accelerometers.

We’ve seen spies use tiny bugs to track their targets in movies. These light flying robots could have very valuable applications in the real world, for example supporting search and rescue missions, inspecting dangerous sites, and even exploring space. Despite their potential, the realization of these robots has so far proven difficult, mainly due to the technical issues encountered in trying to stabilize their flight and simulate flight capabilities such as those insect

Researchers at the University of Washington have recently developed a flight control and wind sensing system that can help solve this challenging robotics problem, ultimately enabling stable flight for robots as small as gnats. This device is based on the use of accelerometers, a sensor that can measure the acceleration of any moving device, object or body.

Integrating gyroscopes into the device could theoretically help overcome the technical issues associated with flying small flying robots, the gyroscopes available today are nowhere near as light or efficient as of what they need to fly such light devices. The lightest gyroscope developed so far weighs 15mg, which is 5mg more than the weight of the entire gnat-sized robot.

Accelerometers are not only lighter than gyroscopes but when combined with good models of robot dynamics, they can estimate the in-flight tilt angle of robots. The researchers also included the same light optic flow sensor, and a small microprocessor, to also estimate the height of a robot and the wind speed.

They tested the robot system in both simulations and real-world experiments using a 30-gram robot and found that it successfully stabilizes its flight, allowing it to mimic the dynamics of flight of fruit flies. In the future, they hope it can be used and tested in many other flying robots, including lighter robots that weigh 10 mg or less.