What is a microbot?
A very small robot that can be directed by operators through the use of electromagnetic fields. The size of these devices can be measured from as small as a few nanometers to several millimeters. Microbots can work alone or in groups exhibiting swarm behavior. In a swarm they communicate with each other and coordinate actions. It is all very sci-fi. Remember Michael Crichton’s “Prey?” The book told the story about microbots escaping from a laboratory and becoming a self-sustaining, self-reproducing, intelligence. You would think the story would have scared researchers from even considering developing the real thing.
But that hasn’t happened because microbots even in swarms are a useful technological innovation. It is their tininess that makes them so powerful. Microbots contain no on board means of locomotion, which begs the question, just how did Crichton’s microbots manage once outside the confines of their laboratory?
In the real world of microbots the technology responds to external magnetic fields. But unless an application requires all microbots to act the same, it would seem the devices would have little real world application. The trick, therefore, is to make each microbot work individually. That requires external magnetic controllers sensitive enough to manipulate each individual precisely without affecting others in the immediate surroundings.
That’s what engineers at Purdue University set out to do. They built a magnetic controller that can operate individual microbots within a group. They did this by creating tiny coils that alternate attractive and repulsive forces. This allowed them to manipulate individual 2 millimeter-sized microbots within a group. Now the team is working on the next generation of even smaller microbots measuing 250 micrometers (0.25 millimeters) in diamter. Their current success has been described in a paper appearing in this month’s issue of the journal Micromachines.
SRI International, whose Motobot (the motorcycle riding robot featured at this January’s Consumer Electronics Show) excited the crowd, has also been experimenting with magnetically-activated microbots. In a posted YouTube video SRI’s version of microbots can be seen crawling at real-time speeds of 35 centimeters per second. In another segment you watch microbots doing a variety of assembly tasks in a coordinated process. SRI sees these types of microbots as integral to manufacturing, building integrated circuits and smart structures.
But that’s not all, biomedical engineers are exploring how to manipulate robot molecules and use them as surgical instruments. They call their invention, nanorobots, tiny charged particles that work in concert within blood vessels. Applications include unblocking occluded arteries.
At Drexel University, MinJun Kim, is working with an international team from the United States, Switzerland and South Korea to perfect nanobots controlled by magnetic resonance imaging (MRI) machines. After all an MRI uses magnets to create images. This new MRI application turns the machines into command and control centers capable of steering molecule-sized nanobots through the bloodstream while watching them do their work.
Right now the nanobots are only being tested in animal studies. After these molecular machines blast through a clog in an artery they will swim away and biodegrade. If all goes well human clinical trials are expected to start in 2019.
In 1976 NASA and the Jet Propulsion Laboratory created and launched the two Viking Martian landers. On board were two robotic arms controlled by a microcomputer. These were the arms that dug the first soil samples from the Martian surface hatching the controversy about whether Mars harbored life or not, a question that remains unanswered to this day.
Today most robots can be found in manufacturing or the military. A few are finding their way into domestic use such as the iRobot line of Roomba vacuum cleaners. Robots are continuing to change, becoming faster, more nimble, capable of specializing in a single task or being used for multiple tasks.
Compare the T3 seen above with the articulated robotic arm on Curiosity, the Mars Science Laboratory (seen below). You can see that in a matter of less than 40 years robotic arms have dramatically improved. Curiosity’s arm is 2.1 meters (7 feet) in length and unlike the T3 which served a single purpose, this arm includes a set of tools with wide ranging application. The arm has an on board colour camera that features a high resolution zoom lens. In addition the arm has a drill, alpha particle x-ray spectrometer, a CheMin mineral and chemical analyzer, SAM, an atmospheric gas analyzer, RAD, a radiation detector, DAN, a hydrogen, ice and water detector, and a scoop for recovering and testing surface and sub-surface soil samples. The arm is dexterous and capable of turning almost an entire full circle.
Where Robots are Going From Here
The next evolution of robots is taking us well beyond specialty robots and into the realm of more generalized usage. This comes courtesy of a number of organizations including one that recently made the news, Rethink Robotics, an offshoot of the robotics program at Massachusetts Institute of Technology. The company’s founder is Rodney Brooks, a co-founder of iRobot. At Rethink the mission is to make robots fit places where automation has never been practiced, in particular, small and mid-size businesses. Rethink robots will be designed to learn and become productive a few hours after coming out of the box. Each will be capable of working collaboratively with nearby humans. Each will have fine motor control, machine vision, tactile touch sensors, and multiple arms. And each will be easily reconfigurable for new work assignments.
Rethink is joined by other companies in a race to produce new robotic capability that will broaden the technology’s usage in business and in our personal lives. Among these are:
Open Source Comes to Robotics
Willow Garage is a company founded by Scott Hassan in 2006 to develop robots for non military applications using open source software to encourage independent third parties to develop the technology further. Willow Garage has developed the Robot Operating System or ROS, a library of tools for developers to create robot applications. Through its online Internet forum the software is offered freely to anyone to use, enhance or to build commercial products.
Willow Garage has created the PR2, a robot development platform for testing new robot applications and technologies. PR2 comes with a robotic arm that features a flexible wrist joint and gripper capable of holding everything from towels to brooms. The PR2 has spawned an active research community that includes universities from around the world.
]]>