New sensor designed to give robots a gentler touch – on a budget
By Ben Coxworth
April 18, 2013
A lot of time and energy is currently going into developing technologies that give robots a sense of touch. In particular, scientists are developing things like artificial skin that lets robots know how much pressure they’re exerting on an object – this allows them to firmly grip rugged objects, while being more delicate with fragile items. Although most such technologies are fairly complex and expensive, researchers have now developed a cheap tactile sensor that could bring touch sensitivity to consumer and hobbyist applications.
The sensor is known as TakkTile, and was developed by grad student Leif Jentoft and postdoctoral fellow Yaroslav Tenzer at the Harvard School of Engineering and Applied Sciences.
At the heart of the device is a tiny air pressure-sensitive digital barometer, of the type already commonly used in things like cell phones and GPS units. A layer of rubber is vacuum-sealed onto it. When the sensor is then mounted on a robot’s hand, it’s capable of detecting how much pressure the robot is placing on objects that it’s grasping.
The rubber not only allows for grip and an even distribution of pressure, but it also serves to protect the sensor – it can tolerate up to 25 pounds (11 kg) of direct pressure, and can withstand strikes from hammers and baseball bats. At the same time, however, it can also detect touches as light as one gram.
Along with its use in the field of robotics, TakkTile might also find its way into a variety of other applications – suggestions include toy animals that respond to being petted, or medical devices that are able to gently tease tissue apart.
“Despite decades of research, tactile sensing hasn’t moved into general use because it’s been expensive and fragile,” said Jentoft. “It normally costs about $16,000, give or take, to put tactile sensing on a research robot hand ... The traditional technology also uses very specialized construction techniques, which can slow down your work. Now, TakkTile changes that because it's based on much simpler and cheaper fabrication methods."
The sensor can be seen getting tested in the video below.