Featured Research

from universities, journals, and other organizations

GPS not working? A shoe radar may help you find your way

Date:
December 2, 2010
Source:
North Carolina State University
Summary:
The prevalence of global positioning system (GPS) devices in everything from cars to cell phones has almost made getting lost a thing of the past. But what do you do when your GPS isn't working? Researchers have developed a shoe-embedded radar system that may help you find your way.

The prevalence of global positioning system (GPS) devices in everything from cars to cell phones has almost made getting lost a thing of the past. But what do you do when your GPS isn't working? Researchers from North Carolina State University and Carnegie Mellon University (CMU) have developed a shoe-embedded radar system that may help you find your way.

"There are situations where GPS is unavailable, such as when you're in a building, underground or in places where a satellite connection can be blocked by tall buildings or other objects," says Dr. Dan Stancil, co-author of a paper describing the research and professor and head of NC State's Department of Electrical and Computer Engineering. "So what do you do without satellites?"

One solution is to use inertial measurement units (IMUs), which are electronic devices that measure the forces created by acceleration (and deceleration) to determine how quickly you are moving and how far you have moved. The technology works in conjunction with GPS, with the IMU tracking your movement after you lose a GPS signal -- and ultimately providing you with location data relevant to your last known location via GPS. For example, if you entered a cave and lost your GPS signal, you could use the IMU to retrace your steps to the last known GPS location and find your way back out.

However, IMUs have traditionally faced a significant challenge. Any minor errors an IMU makes in measuring acceleration lead to errors in estimating velocity and position -- and those errors accumulate over time. For example, if an IMU thinks you are moving -- even as little as 0.1 meters per second -- when you are actually standing still, within three minutes the IMU will have moved you 18 meters away from your actual position.

But, "if you had an independent way of knowing when your velocity is zero, you could significantly reduce this sort of accumulate error," Stancil says.

Enter the shoe radar.

"To address this problem of accumulating acceleration error, we've developed a prototype portable radar sensor that attaches to a shoe," Stancil says. "The radar is attached to a small navigation computer that tracks the distance between your heel and the ground. If that distance doesn't change within a given period of time, the navigation computer knows that your foot is stationary." That could mean that you are standing still, or it could signal the natural pause that occurs between steps when someone is walking. Either way, Stancil says, "by resetting the velocity to zero during these pauses, or intervals, the accumulated error can be greatly reduced."

In other words, the navigation computer compiles data from the shoe radar and the IMU and, by incorporating the most recent location data from GPS, can do a much better job of tracking your present location.

The paper, "A Low-Power Shoe-Embedded Radar for Aiding Pedestrian Inertial Navigation," is published in the October issue of IEEE Transactions On Microwave Theory And Techniques. The leader author of the paper is Dr. Chenming Zhou, who did the work while a postdoctoral research associate at CMU. Co-authors are Stancil, and CMU's Dr. Tamal Mukherjee and James Downey. The work was supported, through CMU, by the Air Force Research Laboratory and the Defense Advanced Research Projects Agency. This release is approved for public release, distribution unlimited.

NC State's Department of Electrical and Computer Engineering is part of the university's College of Engineering.


Story Source:

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


Journal Reference:

  1. Chenming Zhou, James Downey, Daniel Stancil, Tamal Mukherjee. A Low-Power Shoe-Embedded Radar for Aiding Pedestrian Inertial Navigation. IEEE Transactions on Microwave Theory and Techniques, 2010; 58 (10): 2521 DOI: 10.1109/TMTT.2010.2063810

Cite This Page:

North Carolina State University. "GPS not working? A shoe radar may help you find your way." ScienceDaily. ScienceDaily, 2 December 2010. <www.sciencedaily.com/releases/2010/12/101201102557.htm>.
North Carolina State University. (2010, December 2). GPS not working? A shoe radar may help you find your way. ScienceDaily. Retrieved April 17, 2014 from www.sciencedaily.com/releases/2010/12/101201102557.htm
North Carolina State University. "GPS not working? A shoe radar may help you find your way." ScienceDaily. www.sciencedaily.com/releases/2010/12/101201102557.htm (accessed April 17, 2014).

Share This



More Matter & Energy News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Small Reactors Could Be Future of Nuclear Energy

Small Reactors Could Be Future of Nuclear Energy

AP (Apr. 17, 2014) After the Fukushima nuclear disaster, the industry fell under intense scrutiny. Now, small underground nuclear power plants are being considered as the possible future of the nuclear energy. (April 17) Video provided by AP
Powered by NewsLook.com
Honda's New ASIMO Robot, More Human-Like Than Ever

Honda's New ASIMO Robot, More Human-Like Than Ever

AFP (Apr. 17, 2014) It walks and runs, even up and down stairs. It can open a bottle and serve a drink, and politely tries to shake hands with a stranger. Meet the latest ASIMO, Honda's humanoid robot. Duration: 00:54 Video provided by AFP
Powered by NewsLook.com
German Researchers Crack Samsung's Fingerprint Scanner

German Researchers Crack Samsung's Fingerprint Scanner

Newsy (Apr. 16, 2014) German researchers have used a fake fingerprint made from glue to bypass the fingerprint security system on Samsung's new Galaxy S5 smartphone. Video provided by Newsy
Powered by NewsLook.com
Porsche CEO Says Supercar Is Not Dead: Cue the Spyder 918

Porsche CEO Says Supercar Is Not Dead: Cue the Spyder 918

TheStreet (Apr. 16, 2014) The Porsche Spyder 918 proves that, in an automotive world obsessed with fuel efficiency, the supercar is not dead. Porsche North America CEO Detlev von Platen attributes the brand's consistent sales growth -- 21% in 2013 -- with an investment in new technology and expanded performance dynamics. The hybrid Spyder 918 has 887 horsepower and 944 lb-ft of torque, but it can run 18 miles on just an electric charge. The $845,000 vehicle is not a consumer-targeted vehicle but a brand statement. Video provided by TheStreet
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