Tag Archives: Sacha the Stanford Carbon Nanotube Controlled Handshaking Robot

Shake hands with Sacha, a robot controlled by carbon nanotube transistors

Since we use computer chips built from silicon in any number devices including robots, the announcement of a robot controlled by the first computer chip built entirely of a material other silicon bears notice. From the Mar. 15, 2013 news item on Nanowerk (Note: Links have been removed),

A group of Stanford researchers recently debuted the first robot controlled by a computer chip built entirely from carbon nanotube transistors, which many scientists predict may eventually replace silicon.

While scientists have produced simple demonstrations of working carbon nanotube circuit components in the past, the Stanford team, led by Professor of Electrical Engineering Philip Wong and Associate Professor of Electrical Engineering and Computer Science Subhasish Mitra Ph.D. ’00, was able to demonstrate an actual subsystem composed entirely of the material.

The news item was originated by a Mar. 7, 2013 article by Nikhita Obeegadoo for the Stanford Daily, where she noted,

The project was presented in the form of a robot named Sacha at the 2013 International Solid-State Circuits Conference (“Sacha, the Stanford Carbon Nanotube Controlled Handshaking Robot”), which was held in San Francisco. According to Mitra, the robot was created to demonstrate the development of a system that can function despite the errors caused by inherently imperfect nanotubes, which have posed issues for research teams working with carbon nanotubes in the past.

“Through several generations of technology, devices keep getting smaller and denser, and silicon will no longer be the best material for the purpose in about ten years,” Guha [Supratik Guha, director of physical sciences at IBM’s Yorktown Heights Research Center] said. “For needs that are close to atomic dimensions, carbon nanotubes have just the right shape and the right electrical behavior.”

Eric Juma on his eponymous blog offers more insight into the project in his Mar. 16, 2013 posting,

… The robot contained a carbon nanotube capacitor, a device found in many touchscreens, connected to another nanotube circuit, which turned the analog signal from the capacitor into a digital signal, which was transmitted to the microprocessor that contained CNT transistors. The microporcessor then sent a signal to a motor on the hand of the robot, which shook the person’s hand that touched the capacitors embedded in it.

This is not the first example of carbon nanotube circuitry, but it is the first example of CNTs being produced at mass for a microprocessor and circuit that were integrated. This advancement showed that it is possible to produce mass amounts of CNTs and have them integrate succesfully into a complex system. Although the size of the CNTs in this system are far from the optimal size of 10nm, it is a good starting point, and the nanotubes still can be much further refined.

Carbon nanotubes, although perfect in theory for microprocessors, present new challenges for engineers. The greatest challenge is the actual integration of CNTs into circuitry. Nanotubes often force themselves into a tangled position, which can cause circuits to fail without warning.

Juma gives a good explanation for why there is so much interest in carbon nanotubes in the field of electronics and he provides links to more information about it all. (There’s a video about carbon nanotubes and their various shapes and structures in my Mar. 15, 2013 posting about them.)

Sacha will be seen (or perhaps the work will simply be presented by Max Shulaker?) next in Switzerland at a Mar. 25, 2013 workshop (FED ’13; Functionality-Enhanced Devices Workshop) at the EPFl (École Polytechnique Fédérale de Lausanne.