April 18, 2013
New Tactile Sensor Enables Robots To ‘Feel’ What They’re Holding
Enid Burns for redOrbit.com — Your Universe Online
When we think of robots, we typically think of the metal behemoth from Forbidden Planet, or Rosie from The Jetsons. In reality, many companies use robots to manufacture, pack and transport goods. However, they are often an arm fixed to the floor or other surface. These robots are heavy, strong, and do their job without sensing the needs of what they´re holding. That is, unless there are sensors so the robot can detect the weight and force of what's in its grasp. These solutions are often expensive.Researchers at the Harvard School of Engineering and Applied Sciences (SEAS) have developed a tactile sensor for robot hands sensitive enough to detect a light touch, yet durable enough to withstand the force of a hammer. The sensor is also inexpensive to produce.
Within the School of Engineering and Applied Sciences, the Harvard Biorobotics Laboratory designed the sensor, which is called TakkTile. The new sensor is inexpensive and intended to be more accessible for small inventors and companies.
"Despite decades of research, tactile sensing hasn't moved into general use because it's been expensive and fragile," said co-creator Leif Jentoft, a graduate student at SEAS. "It normally costs about $16,000, give or take, to put tactile sensing on a research robot hand. That's really limited where people can use it. 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."
Jentroft worked with co-creator Yaroslav Tenzer, a postdoctoral fellow.
TakkTile uses a tiny barometer in order to sense air pressure. On top of that, a layer of vacuum-sealed rubber is applied. The rubber protects the sensor from weight and force of up to 25 pounds.
One application is to use the TakkTile sensor on a robot hand. When in use, the robot "knows what it's touching. It can pick up a balloon without popping it. It can pick up a key and use it to unlock a door," a statement on the research said.
The TakkTile sensor can be used on more products and devices than a robot hand. The engineers suggest the sensor could be used inside a toy stuffed puppy that responds to petting. Other uses include medical devices, such as a laparoscopic gripper, that can be used in surgery.
"Not everyone has the bandwidth to do the research themselves, but there are plenty of people who could find new applications and ways of using this," said Tenzer.
Unlike most robotic sensors, the TakkTile can be built using relatively simple equipment. They are made from a patented process that relies on standard methods used in printed circuit board fabrication, along with access to a vacuum chamber. The tiny barometers used to construct the TakkTile sensor are available cheaply and have been widely used in cellphones and GPS units to sense altitude.
Researchers Jentroft and Tenzer worked with their advisor, Robert D. Howe, Abbott and James Lawrence Professor of Engineering at SEAS. The team is pursuing commercial opportunities for TakkTile which could be used to benefit the Office of Technology Department. Harvard plans to license the technology to companies that will provide prefabricated sensors, or integrate TakkTile sensing into products such as robots, consumer devices and industrial products.