Many robots have been designed to move, work, and interact with the world the way that people do. But several researchers are designing robots and microrobots to do things that humans aren’t so great at—namely swimming, flipping, and flying—as efficiently and effortlessly as some animals and microorganisms.
Their work was highlighted on 30 April at “Robots: Inspired by Nature,” a Q&A session that took place at the Painted Bride Art Center as part of the Philadelphia Science Festival. The annual weeklong festival included hands-on workshops for kids as well as presentations by experts on the latest breakthroughs in engineering, astronomy, the life sciences, and other fields.
The Q&A session, moderated by Mike Ilagan, editor in chief of Geekadelphia magazine, gave the researchers a chance to show off their prototypes, including a robotic fish and a drone that could dive through the air and pick up an object as deftly as hawks snatch fish from a river. (The hawk that sat with its handler on stage might beg to differ).
JUST KEEP SWIMMING
Brooke Flammang, an assistant professor of biomechanics and head of the Flammang Lab at the New Jersey Institute of Technology, Newark, joined IEEE Member Gabe Carryon, a researcher at Philadelphia’s Drexel University, to show the audience what they had learned about the mechanics behind how fish swim.
After teaming up with Flammang to study the pectoral or side fins of fish and the way these appendages help them swim and sense obstacles, Carryon built a prototype of a swimming robot that could glide through water and navigate its surroundings with minimal effort. The robot is about 50 centimeters long and 15 cm wide and is modeled after a bluegill fish. Bluegills travel and change directions at high speeds using synchronized fin movements. Their flat, slender bodies lower water resistance and allow them to move effortlessly through water.
If engineers can design a robot to move as naturally and effortlessly as a fish, they can also design submarines and autonomous underwater vehicles that are more energy-efficient and able to adapt to hostile oceanic environments, Carryon noted. The U.S. Office of Naval Research is supporting the researchers’ project with a US $1.1 million grant from the National Science Foundation.
LISTEN TO YOUR GUT
It’s difficult enough to build robots that can accomplish what you want them to do, so imagine building bots that you can only see under a microscope. That’s what two presenters from the University of Pennsylvania, in Philadelphia, are trying to do with a new project that will manipulate and control intestinal bacteria. IEEE Graduate Student Member Denise Wong is a researcher in the university’s Multi-Robot Systems Lab, and Jeffrey Carey is earning a Ph.D. in molecular biology.
Wong, Carey, and a team of researchers from across the university’s engineering and biology departments have harnessed the sensing, swarming, and swimming abilities of bacteria to use them as tiny motors for plastic, microscopic robots. Unlike traditional robots, these robots can’t move on their own—they need the bacteria to propel them. The researchers set their sights on bacteria from the stomach, Wong says, because it’s easy to grow and can move around efficiently. The single-celled organisms are able to push the microbots, which are gear-shaped, by forming large groups or swarms. The researchers control the movement of the bacteria by shining a blue light at the center of the gear. This causes the bacteria to scatter to the edges of the robot and move it around in relation to where the light is being pointed.
Although they’ve yet to gain precise control over the swarms, Wong says these microbots might eventually be used to deliver drugs within the human body to kill cancerous tumors, for example. Carey adds that they might also one day be deployed in bodies of water to clean up toxic waste and other pollutants at the molecular level.
ON THE GROUND AND IN THE AIR
Very few robots can move around on anything but a hard, flat surface, notes IEEE Graduate Student Member Gavin Kenneally. He and a team of researchers at UPenn are trying to change that by studying the way lizards and other reptiles crawl and jump across rough, uneven terrain.
Kenneally, who is pursuing a Ph.D. in mechanical engineering, demonstrated RHex: a versatile hexapedal (six-legged) robot that can crawl, flip, and even leap over grass, mud, rocks, and sand. The robot has a central computer with six actuators that rotate its curved legs. The original robot was developed by the U.S. government’s Defense Advanced Research Projects Agency (more commonly known as DARPA) and has been adapted over the years to be both an educational tool and a research bot. Currently, its movements must be programmed beforehand. However, the researchers aim to develop an autonomous prototype that can deliver food and emergency supplies to dangerous areas and even rescue soldiers.
Elsewhere at the university, Justin Thomas and other researchers from the General Robotics, Automation, Sensing and Perception Lab are taking a cue from hawks and other predatory birds. The IEEE graduate student member and Ph.D. candidate helped develop quadrotor drones outfitted with cameras that can fly, locate and grab objects, and even perch on a tree branch or the side of a cliff or a building and rest there to save energy.
Alicia DeVane, a wildlife conservation expert at the Philadelphia Zoo, brought a red-tailed hawk on stage to compare and contrast the drone to the bird that inspired the researchers. The drone was about 30 centimeters, or about half the size of the hawk, but was just as light as the bird—weighing only about 2 kilograms. Although the drone’s cameras may not spot targets as easily as a hawk spots a fish or a rodent, the drone, like the hawk, can navigate its surroundings without GPS. Thomas said the drones might one day be used in search and rescue missions, environmental monitoring, and farming.