CAMBRIDGE, MA—When GPS isn’t available to pinpoint location, wearable technologies that rely on this information can run into problems. That’s the case when augmented reality glasses can’t get a GPS signal—particularly when traveling long distances in unknown environments. Without location accuracy, information that’s supposed to be overlaid graphically on views of the real world does not appear aligned to the user.
Now, engineers at Draper have devised a way for an augmented reality (AR) system to work accurately without GPS over large areas of operation. The way in which they use a navigation system to maintain alignment between the real world and the digital world of augmented reality has earned its inventors a patent.
“Many current inertial navigation systems benefit from, or require, known points of reference or mapping technology to maintain the positional accuracy of AR elements,” said Eric Jones, a Principal Human Factors Engineer at Draper. “Our system is configured so that it can operate in unknown environments without needing to build a virtual map or use such a map to estimate location and orientation.”
Immersive reality—the practice of using augmented or virtual reality (VR) technologies to enhance an experience—is growing in adoption. Newspapers are trying it out in order to retain readers, and big box retailers are field testing it to see if it will improve the customer experience. Even the U.S. Army has equipped soldiers with AR-eyewear that places simulated images in view of real-world environments, enhancing their situational awareness.
Jones and his colleagues focused on sailors at sea as one of their use cases. Jones said, “Sailors wearing AR headsets for training or other purposes can find their systems failing as their ship rolls and when GPS is unavailable. This is especially true when below deck: the vision-aided navigation system is going to sense the roll, but the camera is not going to detect any change in the image. The solution will degrade, and AR registration accuracy will be lost. But if we can disentangle the movement of the ship from the movement of the user, by using a separate off-board system, for example, the device can calculate that the sailor’s position has not changed.”
For sailors who must train and operate at sea in all conditions, robust performance is crucial, Jones added. “Our aim is trusted accuracy, seamlessly integrated, in operational settings,” he said.
The U.S. Patent Office credits James Laney, Richard W. Madison, Robert Truax, Theodore J. Steiner, III and Jones as inventors for “Egocentric Odometry System for Maintaining Pose Alignment between Real and Virtual Worlds.”
The current patent adds to Draper’s portfolio in human systems technology. Recently, Draper participated in a technology demonstration for U.S. government officials to show a proof-of-concept hand-held AR system which allows small soldier units to place digital elements in their view of the real world, as seen through their displays, and leave these elements as "virtual breadcrumbs" visible to others using the same system.