Product Search

 
Call Us 800-628-0885 or 1-703-256-8900
 
Item Added to Cart
 
 
 

Project Descriptions

 

NavtechGPS Project Overviews

Boomerang project with heading GPS

NavtechGPS played a small but critical role in the development of the Boomerang. The Boomerang is a state-of the-art shooter detection system developed by Raytheon BBN Technologies to precisely locate incoming small arms fire, primarily from snipers. Often, troops in noisy Humvees (HMMWV) in combat arenas like Iraq and Afghanistan didn’t know they were being shot at until someone was hit.
 
The Boomerang uses an acoustic detection system that employs an array of microphones mounted to a vehicle to detect incoming gunfire. NavtechGPS developed a solution to determine the heading of the vehicle in order to properly detect the orientation of the microphone array. After careful consideration, NavtechGPS chose a precision GPS heading system and robust patch antennas. We were further challenged to find a way to prevent possible jamming and interference to the GPS receiver. Through the addition of proper filtering, we were able to mitigate these issues to a degree even greater than requested by the customer.
 
    Boomerang with Vehicle

ScanEagle and Integrator UAVs, navigation and capture

The Insitu Inc., ScanEagle™ is an unmanned aircraft system (UAS) used for reconnaissance. The Integrator™ UAS is similar to the ScanEagle™, but can carry out longer missions with larger payloads which can be easily integrated into the vehicle. While the ScanEagle™ project was still in its formative years, NavtechGPS was asked to find a suitable GPS receiver and antenna to guide the ScanEagle™ UAV during missions and, more importantly, for its capture. The UAV is a pusher prop and was to be recovered by flying it into a cable on a moving ship while the aircraft was also moving with different and sometimes opposite dynamics. After working with Insitu for several months to evaluate the various options we recommended to them, Insitu settled on our initial GPS receiver system recommendation.
 
Over time, NavtechGPS worked with the manufacturer of the GPS receiver system to enable the system to work in different environments, expanding the capabilities of the UAS for different mission types and areas of the world. The GPS receiver system NavtechGPS designed for the ScanEagle™ is still in use today.
 
  ScanEagleIntegrator_Cir_W240

Parking enforcement project with heading GPS

Today, many municipalities across the United States and in Canada, employ the autoChalk™ digital chalking and license plate recognition (LPR) system developed by Tannery Creek Systems Inc. Before autoChalk, parking enforcement meant manually chalking the tires of parked cars by law enforcement officials to see if the cars overstayed the meter — an expensive use of valuable law enforcement resources.
 
NavtechGPS was brought in on the developmental stages of this now popular parking enforcement system to outfit automated parking attendant vehicles with heading-based GPS receivers. The system used a two-antenna and two-GPS-receiver system to provide vehicle heading information even when standing still. The GPS position data was used to locate, then later relocate the subject vehicles by integrating the GPS data with a photographic video recognition system to catch violators.
  ParkingEnforcement_Cir_W240

DARPA Grand Challenge Course Layout

2018 finds driverless cars in various advanced testing stages—with multiple companies focused on bringing driverless cars to public roads. Much of that progress results from an innovative race that began in 2004, The DARPA Grand Challenge. 

Funded by the Defense Advanced Research Projects Agency with the goal of accelerating the development of autonomous vehicle technology, the Grand Challenge was the first long-distance race for autonomous vehicles. The original challenge course ran from Bristow, CA to Primm, NV—some 150 miles across the Mojave Desert region.

The prize: $1 million dollars. But before there could be a race, the course needed to be mapped to a high accuracy—a process that posed several unique challenges. DARPA knew external GNSS expertise was needed, and it chose NavtechGPS for the job.

Gathering info and creating the course map, which DARPA would disseminate to participants through a GIS-like system, required precise mapping of the latitude, longitude and altitude of obstacles, hills, and other environmental features.

The desert location, while ideal for the fledgling race because it was free of buildings, traffic and people, did not offer surveyed landmarks for validating coordinates. NavtechGPS was able to solve this.

As temperatures rise through the day, the sun warms the ionosphere above the GPS user, and it bends in a mostly unpredictable way. The longer path causes an increased length of travel for an RF satellite signal. Because the signal now takes several nanoseconds longer to arrive at the user’s antennae, the position becomes inaccurate, usually by several feet. In fact, a difference of one billionth of a second can throw off measurement by 12 inches; a delay of nine nanoseconds can result in a discrepancy of 19 feet. This refraction mostly impacts GPS receivers using single frequency receivers (like GPS in cars or smart phones).

With 2004 technology, handheld GPS receivers were available, but they did not deliver the accuracy needed for mapping the course. In fact, L1 (single frequency) receivers had a margin of error of two to three meters (six to nine+ feet) at the time. NavtechGPS recommended dual frequency receivers, which used a second GPS frequency (L2) and autonomously delivered accuracy within one meter and eliminated ionospheric issues.

But because the Grand Challenge course required even more accurate measurements and positioning, NavtechGPS recommended a private SBAS (Satellite Based Augmentation System) instead of local reference stations because of the large area being covered.

  2005-DARPA-Grand-Challenge-Stanley2_W240
 
 
 
--> NavtechGPS, Suite 230, 5501 Backlick Road, Springfield, VA 22151-3940 USA