This work is licensed under a Creative Commons Attribution - NonCommercial - ShareAlike 2.5 License. Copyright © 2006 Nathan Foster, some rights reserved.
Scientists Ravi Saraf and Vivek Maheshwari have created a touch sensor with about the same resolution as the human fingertip. It is a thin film of metal and semiconducting nano-particles that emit light when pressure is applied. A report of the device appeared in the June 9th issue of Science Magazine. Professor Engineer Ravi Saraf said he wants to follow up the research with a device that closer mimics human touch by detecting temperature changes as well texture.
The sensor has potential medical applications. Ravi Saraf told the BBC, "The hope is that if you have the resolution close to a human finger in applications like minimal invasive surgery, where the surgeon could actually 'touch' while he or she is doing the procedure and tell if the tissue is cancerous or abnormal etc, that would increase the success of these surgeries."
As pressure is applied, current is tunneled through alternating layers of Aluminum and Cadmium Sulphide. The Cadmium Sulphide layers react by emitting visible light, which can be detected by a camera. The amount of current change is linearly proportional to the stress applied to the film.
The resolution of this device is at least ten times more accurate than other touch sensors that are available. Dr. Richard Crowder wrote in Science Magazine, "The development of tactile sensors is one of the key technical challenges in advanced robotics and minimal-access surgery."
Morelle, Rebecca. "Robot device mimics human touch." BBC News. 8 June 2006. 11 June 2006, <http://news.bbc.co.uk/2/hi/science/nature/5056434.stm>
Maheshwari, Vivek and Ravi F. Saraf. "High-Resolution Thin-Film Device to Sense Texture by Touch." Science. 9 June 2006. 11 June 2006, <http://www.sciencemag.org/cgi/content/full/312/5779/1501>
Crowder, Richard. "APPLIED PHYSICS: Toward Robots That Can Sense Texture by Touch." Science. 9 June 2006. 11 June 2006, <http://www.sciencemag.org/cgi/content/full/sci;312/5779/1501>
Note that the two science mag articles can be found in their print magazine, with the following citations:
Maheshwari, Vivek and Ravi F. Saraf. "High-Resolution Thin-Film Device to Sense Texture by Touch." Science 312 (2006): 1501-1504.
Crowder, Richard. "APPLIED PHYSICS: Toward Robots That Can Sense Texture by Touch." Science 312 (2006): 1478-1479.
This work is licensed under a Creative Commons Attribution - NonCommercial - ShareAlike 2.5 License. Copyright © 2006 Nathan Foster, some rights reserved.