Low-cost silicone robots that walk, change color to match their surroundings, and light up in the dark may soon be added to the array of robots (discussed here and elsewhere) that are helping first responders and the military.
The soft, vaguely starfish-shaped robot is equipped with microfluidic channels. The networks of these channels are contained in thin silicone sheets, called color layers. Air and other fluids (such as water, heated or cooled dye, and fluorescent or chemiluminescent solutions) are pumped through the color layers. Depending on the combination, they can change the robot's surface temperature, color, luminescence, and shape, letting it blend with its environment. Alternatively, the robot can glow with the help of chemiluminescence or fluorescent fluids.
Low-cost silicone robots can walk, change color to match their surroundings, and light up in the dark, promising help for first responders and the military. (Source: DARPA)
The robot's movement is controlled by pneumatically pressurizing and inflating the channels. When filled with fluid, it moves at approximately 40 meters per hour. Without the fluid, the speed rises to about 67 meters per hour. Though future research will focus on smoothing its movements to improve the speed, the researchers say the robot's flexibility is more important.
DARPA is interested in soft robots because they are flexible and resilient and can change their shape to maneuver through tight spaces. In the video below, the researchers demonstrate the robot's abilities using tethers that are attached to the control system and pump pressurized gases and liquids into the robot.
Though future versions may incorporate power sources and pumps in the robot itself, operating it with tethers reduces its size and weight. The current rate of pumping (2.25ml per minute), produces a color change in the robot after 30 seconds. After the color layers are filled, they can sustain their color without additional power.
The shapes are made with molds produced with a 3D printer and cost less than $100 each. To date, developing robotics technologies that can be used for Department of Defense applications hasn't been cheap. DARPA says the soft robots' low cost helps overcome one of the major obstacles to DoD adoption of robot technology.
Last year, some of the same researchers developed the first soft silicone robots, modeling them after cephalopods such as squid, which produce instantly changeable camouflage patterns and communicate with colored inks and bioluminescence. In search-and-rescue operations, the new robot could fluoresce to stand out in a dark corridor and guide first responders to injured people.
The robot may also have medical applications. They could be incorporated into prosthetics technology, for example, and the ability to simulate blood vessels and muscle motion may help doctors plan surgeries.
Good point, Ann. At first I thought the robot was calling for the chemicals remotely, just because too much was needed for the package. But after viewing the video again, you're right. It does look like they might be pumped due to human intervention.
Jack, how those colors are determined wasn't specified, but at this point I'm reasonably certain the robot is not doing the choosing. I have several unanswered questions about how the robot will work in the next rev, which is supposed to be untethered. Once of them is: where will the multiple fluids used for color changes come from? Will it be pre-resident in different layers? And what about the pumping action? In the video, the pumping, at least, appears to be done by the operator in real time.
Ann, maybe I missed it, but do you know how the color is determined? Is this a case where the human operator decides how the robot will blend in to its surrounding and then give a command through the various chemical reactions, or does the unit decide for itself what to do?
Rob, the researchers did say that the next step is to develop this robot so it works without a tether. Whether this guy can take advantage of that flexible battery, who knows, but that sounds like a great idea.
Even in the video you posted, Ann, you can see that this robot would be able to squeeze through a small area. It has a gummy worm aspect of flexibility. If they can move beyond a tether -- say, with the flexibile battery you wrote about last week -- http://www.designnews.com/author.asp?section_id=1392&doc_id=249722 -- this could go through all sorts of small spaces.
Rob, I think you nailed that--surveillance is supposed to be one of the major apps this robot would be good for. I can see it taking many different forms, too. Hope they get a better video for the next rev.