December 14, 2012      

Think about the possibilities: really small, totally autonomous flying robots or flying quadrotors that swarm, sense each other and form impromptu teams.

Robots about a foot in scale, weighing about a pound that could fly low to the ground, indoors, or through forests and caves. Robots that could be used to respond to emergencies inside buildings.

Robots that could be used for construction operations like carrying beams or columns and assembling them into structures. Robots that could be sent into buildings after natural disasters to determine if there?s any damage or into reactor buildings to map radiation levels after accidents.

Autonomous Agile Aerial Robots

Vijay Kumar, a professor at the University of Pennsylvania, has already imagined such possibilities. He and his team have developed tiny flying robots dubbed Autonomous Agile Aerial Robots?small aerial robots that can operate in three-dimensional environments and that present many opportunities for roboticists.

vijay's lab

?We work with aerial robots at the smaller end of length and mass scale,? Kumar said. ?Our biggest robot is less than two kilos in weight, and about less than one meter in diameter.

Our smallest robot is a handheld robot, which is roughly a little more than one-tenth of a pound, and about eight inches in diameter. Our interests are mostly in functioning in indoor environments.?

Kumar and his team are making small vehicles that are autonomous that can operate in three-dimensional environments and be used in the same settings where people use mobile ground robots.

Rubble, no problem

?You are no longer confronted with locked doors as an obstacle,? he said. ?Rubble is no longer something that can impede your path, as you can fly over it. You can fly through windows, you can enter from the top. So these robots can be used for many things that ground robots are used for. Search and rescue applications, perhaps law enforcement. The military with surveillance applications.?

For example, say law enforcement officials know something is happening inside a building but they?re not sure exactly what. They could send these robots in to scope out the situation before deploying humans.

?If you want to put something in through the window, for instance, it?s hard to take a big bomb disposal robot and stick it in through the window,? Kumar said. ?But you can send little robots in through the window and see what the situation is inside the room, which would be hard to do with a ground robot.?

However, he said these little aerial robots are not able to carry the payload that big bomb disposal robots and ground robots can. But one way to overcome this limitation is to give the robots the intelligence that lets them cooperate to get the job done.

Kumar said he and his team have developed many such micro-aerial robots. Some rely on commercially available platforms that the researchers outfit with their own sensors and processors, then adapt to their applications.


?The robots we build are called quadrotors,? he said. ?They have four rotors. And they have onboard circuitry to allow them to send orientation, attitude, acceleration, and velocity. They use this information to control the four rotors so they are always in a stable configuration.?

Based on what the robots see, or is seen by cameras either onboard, or offboard, these robots essentially figure out where to go. So if you tell them to go in a particular location, then they can essentially go there on their own, Kumar said.

?You can think of robots in a lab interacting with a minicloud inside a lab,? he said. ?They are essentially talking to multiple cameras through a wireless network. They talk to laptops. Some of these robots do very little computing on their own. They rely on lots of computation that is done externally and then they use that information to figure out what to do.?

Automated construction

Kumar and the other roboticists have developed the mathematical framework and the algorithms that enable a robot on its own to reason about its environment and about the other robots and then do what it takes to cooperate with the other robots.

?We have been able to show that we can go into unknown buildings; we can do automated construction,? he said. ?You give the robot a blueprint of what to do and the robots decide where to place the parts, which picks up what and when and where to place it?it?s done autonomously. You will see the robots communicating with each other to figure out how to travel in a formation, and how to change the formation when confronted with an obstacle.?

Biologically-inspired microbots

Harvard Associate Professor of Electrical Engineering Robert Wood is also researching how to design, make, control and analyze biologically-inspired microbots that can be used to answer questions about micromechanics, actuation, fluid mechanics, controls, and microelectronics.

Additionally, this robotic platform can be used in search-and-rescue operations, to monitor the environment as well as to explore hazardous environments, according to information from the Harvard Microrobotics Laboratory.

Mimic the ?intelligence? of a bee colony

mimic the hive

By studying the biology of a bee as well as the bee?s behavior relative to the hive, Wood and the other researchers are advancing the study of miniature robotics.

The researchers are confident that this could help them better understand how to artificially mimic the ?intelligence? of a bee colony. The researchers are also trying to figure out better ways to construct the small-scale flying mechanical devices.

These coordinated agile robotic insects can be used for a number of things including:

  • autonomously pollinating a field of crops
  • search and rescue (e.g., after a natural disaster)
  • exploring hazardous environments
  • military surveillance
  • high resolution weather and climate mapping
  • traffic monitoring

According to the group, coordinating large numbers of small, agile robots, then mimicking the physical attributes as well as the behavioral robustness of insect groups will be enable the robots to accomplish such tasks faster, more efficiently, and more reliably.

The scientists have also designed dynamic hardware and software that serve as the brain for the small robot. This brain controls and monitors flight, senses when a robot is near other objects like its ?relatives??as well as other objects?and helps the robot make simple decisions.

?Talk? to one another?and the hive

To mimic the behavior of a real colony of insects, Wood and his team are using sophisticated coordination algorithms, communications methods (i.e., the ability for individual machines to ?talk? to one another and the hive), and global-to-local programming tools to replicate how real bees rely on each other to go about their daily routines including scouting, foraging, and planning.

But sometimes scientists study the biology of flying creatures to drive innovation in other areas.


Take SmartBird, a project of Festo?s Bionic Learning Network, for instance. Festo?s Bionic projects are aimed at making automation products more energy-efficient so the company can offer its customers new features by means of Bionics, like an adaptive gripper that can handle fragile goods carefully and easily, according to an email from a Festo spokesperson.

SmartBird is an ultralight but powerful flight model equipped with excellent aerodynamic qualities and extreme agility. With SmartBird, Festo has succeeded in deciphering the flight of birds, according to the spokesperson.

The objective of the SmartBird project is to construct a bionic bird modeled on the herring gull that will help Festo develop new and improved products for its customers.

Articulated torsional drive

?The SmartBird is not navigated by GPS, it still needs human guidance and control by a pilot. Nevertheless, it can start, fly and land autonomously?with no additional drive mechanism,? the spokesperson said. ?Its wings not only beat up and down, but also twist at specific angles.


This is made possible by an active articulated torsional drive, which in conjunction with a complex control system makes for unprecedented efficiency in flight operation.?

Because Festo is working on projects in the field of bionics that are innovative and visionary for the industrial automation in the near future, the company investigates topics like lightweight design, adaptive structures, collective behavior, energy efficient movements, etc.

After deciding on these issues, researchers search for examples and principles in nature and in the already existing ?technical world.?

?If we identify an interesting biological model and we develop an idea [about] how we could realize this, we accept the challenge,? the spokesperson said.

The spokesperson said using the technology behind SmartBird, Festo has developed a very light object with a drive system that?s very energy efficient.

The herring gull: the technology-bearer

?This bionic technology-bearer, which is inspired by the herring gull, can start, fly and land autonomously?with no additional drive mechanism,? she said. ?Its wings not only beat up and down, but also twist at specific angles.

This is made possible by an active articulated torsional drive unit, which in combination with a complex control system attains an unprecedented level of efficiency in flight operation.?

Festo has therefore succeeded in creating an energy-efficient technical adaptation of this model from nature. And the functional integration of the coupled drive units yields significant ideas and insights that Festo can transfer to the development and optimization of hybrid drive technology, the spokesperson said.

Festo doesn?t build airplanes or any other aircraft. Rather, SmartBird merely serves as a technological demonstration of how Festo provides innovative automation solutions for its clients, the spokesperson said.

?By analyzing SmartBird?s flow characteristics during the course of its development, Festo has acquired additional knowledge for the optimization of its product solutions and has learned to design even more efficiently,? she said.