Engineers at Harvard University in Massachusetts developed robotic insects with flapping wings, using a microfabrication process that makes it possible to produce these devices in large numbers. The team from Harvard’s School of Engineering and Applied Sciences and Wyss Institute for Biologically Inspired Engineering, led by engineering professor Robert Wood, published its findings in this week’s issue of the journal Science (paid subscription required).
The robotic insects are a product of the university’s RoboBee project that incorporates advances in energy sources, low-power computing, miniature sensors, and algorithms to coordinate multiple independent flying devices. The researchers believe these miniature robotic insects have a variety of potential commercial uses in crop pollination, weather and climate mapping, and traffic monitoring, as well as public safety and national security applications: search and rescue, harzardous environments, and military surveillance. Harvard says its technology transfer office has already started commercializing some of the underlying technologies.
The designers of the robots aim to emulate properties of the common housefly to give them the maneuverability to move laterally, hover, and change directions quickly. Because of these objectives, the research team could not simply miniaturize current robotic designs. “We had to develop solutions from scratch, for everything,” says Wood. Graduate student and co-author Kevin Ma adds, “Large robots can run on electromagnetic motors, but at this small scale you have to come up with an alternative, and there wasn’t one.”
The devices, each weighing 80-milligrams, have a body frame made of carbon fiber, with thin hinges of plastic that serve as joints for the ultrathin wings that flap at 120 times per second. The insects’ wings are powered by strips of ceramic that expand and contract when an electric field is applied, and governed by a system that controls the rotational motions of the device, with each wing controled separately in real time. While the devices are still tethered, they still can adjust for minute changes in airflow — such as flying in windy conditions — that can have outsized effects on items that light and small.
RoboBees take advantage of a production process that prints the devices in multiple layers of materials, such as carbon fiber, titanium, and ceramics, then are laser cut with hinges, to allow for the individual three-dimensional units to assemble in one movement, like a pop-up book. This layering technique is adapted from current semiconductor fabrication techniques, which means the basic tools and processes are already available. “We can now very rapidly build reliable prototypes, which allows us to be more aggressive in how we test them,” says Ma, who adds the team has produced 20 different prototypes in the past six months.
The prototypes are still tethered with thin power cables, because there are no power storage systems small and light enough to be mounted on the insects’ bodies. The researchers say high-density fuel cells will be needed to power the devices independently. Advances in control systems will also be needed to allow for independent and coordinated movements, such as in colonies of devices.
Read more:
- Low Cost Soft-Touch Robotic Sensor Circuits Commercialized
- Robotic Bat Wing Developed to Simulate Flight Dynamics
- Miniature Robots Being Developed to Work in Swarms
- Control Algorithm Developed to Fly Robot Aircraft Indoors
- Mass Production Process Devised for Micro Robots, Devices
* * *
You must be logged in to post a comment.