So, what is RTK GPS, and why is it important?
A standard GPS (Global Positioning System) works by connecting to multiple satellites in space and calculating your position based on where those signals intersect. For most applications, such as driving at 100 km/h on a highway, an accuracy of around 10 to 30 meters is more than sufficient. However, when we need to maintain centimeter-level accuracy from satellites that are around 20,000 km up in space, things get a lot more complicated. This is where RTK (Real-Time Kinematic) GPS comes into play.
RTK GPS takes normal GPS to the next level. As satellites communicate with us, their signals can get delayed due to atmospheric interference, like passing through the ionosphere and troposphere. Here’s the clever part: the RTK system uses a base station that is placed in a fixed, known location near our device (in our case, the buoy bot). Because the base station isn’t moving, it can calculate any errors in the satellite signals, like a delay that might cause the position to appear a few meters off. The base station then communicates this error to the buoy bot, allowing it to correct its position in real time and achieve that centimeter-level accuracy.
Where am I now with this?
I’ve been testing the system, and I’m starting to see the buoy bot hold its position within a much smaller radius in my driveway. This gives me hope that I might have finally figured out how to get RTK GPS working effectively for our project. With this setup, I’m optimistic that I can achieve the precision needed for our buoy bot to perform reliably and stay accurately on station.
I’ll keep you updated on the progress! Hopefully, our Raspberry Pi 5 AI microprocessor kit will arrive soon, which could make things more complicated—but also more exciting.
Best regards and happy sailing,
Graham
FYI
RTK GPS KIT purchase from
Survey Antenna Base & Rover Pair RTK Kit - NavSpark Store (mybigcommerce.com)
