Piksi: GPS at Centimeter Resolution

What could you do with a GPS device that was 100x more accurate than current technology found in cell phones, that is accuracy to the centimeter? 

Researchers, public servants, and high-end maker let the ideas begin: glacier movement tracking, surveying, autonomous cars, fire line progress tracking, and drone/robotic positioning.  The issue is making it affordable.

Colin Beighley and Fergus Noble, known as Swift Navigation, have leveraged past experiences to create the Piksi RTK GPS receiver and have turned to Kickstarter to raise the money for the RTK development, which places the GPS capabilities into centimeter resolution territory. 

Not only are Beighley and Noble shattering the previous $10K price tag level of the capabilities ($500 receivers, two required), but they are open-sourcing the software.  They reached their funding goal on the first day and the Kickstarter completes early in September.

Real time kinematics (RTK) is what provides the resolution increase in the positioning data.  Standard GPS and Piksi additions (41 minutes into video) are explained by the creators in this Youtube video.  It requires two RTK GPS receivers (XBee radio intercommunications) instead of one, making the price point for implementation of a RTK system about $1K. 


RTK Implementation Using Two Piksi Receivers

Normal GPS accuracy is affected by the length of data travel from the positioning satellites and ionospheric delays during the travel.  RTK consists of clever algorithms to compare data and carrier phase to minimize errors and inclusion of a nearby second receiver and inter-communications between both.


RTK Measures Phase of Carrier Wave Compared to Data


RTK Dual Receivers Minimize Ionospheric Error

By the way, it is legal but before you put it on a weapon, fly it above 60,000 feet, or go 1,000 knots or faster, you may want do some research or study export regulations so you don’t end up on a government list or worse!