Researchers have attempted to develop a technique that could revolutionize navigation technologies for drones, robots, and even pedestrians trying to find their way through an airport. The technique measures speed and distance in indoor environments and utilizes a combination of Wi-Fi signals and accelerometer technology that racks devices in near-real time.
"We call our approach Wi-Fi-assisted Inertial Odometry (WIO)," says Raghav Venkatnarayan, co-author of the study. "WIO uses Wi-Fi as a velocity sensor to accurately track how far something has moved. Think of it as sonar, but using radio waves, rather than sound waves. We envision WIO as having applications in everything from indoor navigational tools to fitness tracking to interactive gaming."
Plenty of devices, like smartphones, incorporate technology known as inertial measurement units (IMUs) to calculate how far a device has navigated but these IMUs suffer from large drift errors that exaggerate even then most minute inaccuracy. Although many devices will use GPS to correct their IMUs, this does not apply to indoor signals.
"We created WIO to work in conjunction with a device's IMU, correcting any errors and improving the accuracy of speed and distance calculations," says Muhammad Shahzad, co-corresponding author of the paper and an assistant professor of computer science at NC State. "This improvement in accuracy should also improve the calculations regarding a device's precise location in any indoor environment where there is a Wi-Fi signal."
WIO is a software program, but researchers created a hardware prototype for initial testing with other devices. (Credit: NC State)
"We are currently working with Sony to further improve WIO's accuracy, with an eye toward incorporating the software into off-the-shelf technologies," says Shahzad.
Source: North Carolina State University