Smartphone app determines location, speed and direction of distant objects
By Darren Quick
August 30, 2012
Researchers at the University of Missouri have developed a prototype app that combines a smartphone’s GPS, compass and imaging capabilities to calculate the exact location of distant objects and track their speed and direction. The researchers say the PositionIt app could allow a single off-the-shelf device to replace various pieces of equipment carried by soldiers on the battlefield, or be used closer to home to judge the distance to the green when playing golf.
“The great advantage of a smartphone is that it provides so many tools in a single, readily available, relatively inexpensive package,” said Qia Wang, a doctoral student in MU’s College of Engineering who led the research team. By combining these onboard capabilities, the software Wang and his team have developed can calculate the exact location of distant objects, both when the size of the object is known and when it isn’t.
When the size of the target is known, the software can determine the distance to the target by using a single image captured on the smartphone’s camera and comparing its relative size in the image to the target’s known actual size. The software then combines this distance information with the smartphone’s GPS location and compass reading to calculate the target’s longitude and latitude.
When the size of the target is not known, an additional image needs to be captured so the software can use the two images to triangulate the location of the target. Additionally, the software can also track the direction and calculate the speed of a moving target from a short video captured on the smartphone.
The research team has developed a prototype version of the targeting and tracking software, which is currently undergoing testing. They hope this will provide data that will enable them to improve the speed and accuracy of the software. Advances in smartphone hardware are also expected to improve the performance of the software.
“Currently, our software is limited by the physical abilities of smartphone hardware, but the devices are improving rapidly,” Wang said. “We anticipate that improvements in GPS accuracy, battery life and camera resolution will allow our software to make even more accurate observations. We also are making our software more user-friendly.”
As well as potentially providing soldiers with the capability to precisely locate targets before calling in an air strike without the need for various instruments, such as a rangefinder, GPS, and compass, the researchers say the PositionIt system could be used by golfers to calculate the distance to the green, or by parents to clock a speeding car near a school while catching the offending vehicle on video.
Details on the programming and functionality of the software appears in a paper published in the Proceedings of the Society of Photo-Optical Instrumentation Engineers.
Source: University of Missouri