Featured Research

from universities, journals, and other organizations

Sensitive flow sensor: Hair sensor uncovers hidden signals

Date:
June 6, 2013
Source:
University of Twente
Summary:
An “artificial cricket hair” used as a sensitive flow sensor has difficulty detecting weak, low-frequency signals – they tend to be drowned out by noise. But now, a bit of clever tinkering with the flexibility of the tiny hair’s supports has made it possible to boost the signal-to-noise ratio by a factor of 25. This in turn means that weak flows can now be measured.

Tiny “hairs” of the polymer SU-8 are applied to a flexible, moving surface, the capacitance of which changes with each movement.
Credit: Image courtesy of University of Twente

An "artificial cricket hair" used as a sensitive flow sensor has difficulty detecting weak, low-frequency signals -- they tend to be drowned out by noise. But now, a bit of clever tinkering with the flexibility of the tiny hair's supports has made it possible to boost the signal-to-noise ratio by a factor of 25. This in turn means that weak flows can now be measured. Researchers at the MESA+ Institute for Nanotechnology of the University of Twente (NL) have presented details of this technology in the New Journal of Physics.

These tiny hairs, which are manufactured using microtechnology techniques, are neatly arranged in rows and mimic the extremely sensitive body hairs that crickets use to detect predators. When a hair moves, the electrical capacitance at its base changes, making the movement measurable. If there is an entire array of hairs, then this effect can be used to measure flow patterns. In the same way, changes in air flow tell crickets that they are about to be attacked.

Mechanical AM radio

In the case of low-frequency signals, the noise inherent to the measurement system itself tends to throw a spanner in the works by drowning out the very signals that the system was designed to measure. One very appealing idea is to "move" these signals into the high frequency range, where noise is a much less significant factor. The MESA+ researchers achieve this by periodically changing the hairs' spring rate. They do so by applying an electrical voltage.

This adjustment also causes the hairs to vibrate at a high frequency. This resembles the technology used in old AM radios, where the music signal is encoded on a higher frequency wave. In the case of the sensor, its "radio" is a mechanical device. Low frequency flows are measured by tiny hairs vibrating at a higher frequency. The signal can then be retrieved, with significantly less noise. Suddenly, a previously unmeasurable signal emerges, thanks to this "up-conversion."

This electromechanical amplitude modulation (EMAM) expands the hair sensors' range of applications enormously. Now that the signal-to-noise ratio has been improved by a factor of 25, it is possible to measure much weaker signals. According to the researchers, this technology could be a very useful way of boosting the performance of many other types of sensors.

The study was conducted by the Transducers Science and Technology group, which is part of the MESA+ Institute for Nanotechnology at the University of Twente. It is being carried out in the context of BioEARS (Prof. Gijs Krijnen's VICI project), with funding from the STW Technology Foundation in The Netherlands.


Story Source:

The above story is based on materials provided by University of Twente. Note: Materials may be edited for content and length.


Journal Reference:

  1. H Droogendijk, R G P Sanders, G J M Krijnen. Uncovering signals from measurement noise by electro mechanical amplitude modulation. New Journal of Physics, 2013; 15 (5): 053029 DOI: 10.1088/1367-2630/15/5/053029

Cite This Page:

University of Twente. "Sensitive flow sensor: Hair sensor uncovers hidden signals." ScienceDaily. ScienceDaily, 6 June 2013. <www.sciencedaily.com/releases/2013/06/130606101547.htm>.
University of Twente. (2013, June 6). Sensitive flow sensor: Hair sensor uncovers hidden signals. ScienceDaily. Retrieved April 25, 2014 from www.sciencedaily.com/releases/2013/06/130606101547.htm
University of Twente. "Sensitive flow sensor: Hair sensor uncovers hidden signals." ScienceDaily. www.sciencedaily.com/releases/2013/06/130606101547.htm (accessed April 25, 2014).

Share This



More Matter & Energy News

Friday, April 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Next Stop America for France's TGV?

Next Stop America for France's TGV?

Reuters - Business Video Online (Apr. 24, 2014) General Electric keeps quiet on reports it's in talks to buy French turbine and train maker Alstom. Ivor Bennett reports on what could be an embarrassing rumour for the French government, with business-friendly reforms proving a hard sell. Video provided by Reuters
Powered by NewsLook.com
Raw: Obama Plays Soccer With Japanese Robot

Raw: Obama Plays Soccer With Japanese Robot

AP (Apr. 24, 2014) President Obama briefly played soccer with a robot during his visit to Japan on Thursday. The President has been emphasizing technology along with security concerns during his visit. (April 24) Video provided by AP
Powered by NewsLook.com
Obama Encourages Japanese Student-Scientists

Obama Encourages Japanese Student-Scientists

AP (Apr. 24, 2014) President Obama spoke with student innovators in Japan and urged them to take part in increased opportunities for student exchanges with the US. (April 24) Video provided by AP
Powered by NewsLook.com
UN Joint Mission Starts Removing Landmines in Cyprus

UN Joint Mission Starts Removing Landmines in Cyprus

AFP (Apr. 23, 2014) The UN mission in Cyprus (UNFICYP) led a mine clearance demonstration on Wednesday in the UN-controlled buffer zone where demining operations are being conducted near the Cypriot village of Mammari. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins