What is AgOpenGPS?
AgOpenGPS is a free and open precision farming system that gives your tractor autosteer and section control for a fraction of the price of a commercial system.
The name is short for “Agricultural Open Source GPS”, and it’s the open source part that’s at the heart of it all. Open source means the software is free to download and use, and that you can dig into the source code and make changes yourself if you want to. It definitely doesn’t mean you have to be a hardcore computer nerd to use it, only that the option is there. In other words, the software in an AgOpenGPS system is free. You only pay for the hardware you build around it. Nobody can charge you later for updates or to unlock features. The system is yours.
In short
The system takes your tractor’s position from a GPS antenna, works out where you are relative to the guidance lines you’ve set up, and steers the tractor along them automatically. At the same time, it keeps track of which parts of the field you’ve already covered, so it can switch sections on your seed drill or sprayer on and off to avoid double application.
How it started
Back in 2016, Canadian grain farmer Brian Tischler realized it would be handy to have a system that could show him where he’d already driven, without paying a fortune for a commercial one. With a background in medical electronics and programming experience from game development, he built a map that showed where he’d been, and discovered he could use that same map to switch his seed drill on and off automatically. What started as a driving aid and mapping tool gradually grew into a complete steering system.
Instead of keeping it to himself, he did what farmers do best: he told the neighbors. The project spread to various farming forums, and eventually he made it available for anyone to download on GitHub. Farmers all over the world, many of them not just farmers but also software engineers and programmers, started downloading it, making improvements, sharing tips and hardware suggestions, and giving back to the community. Today, AgOpenGPS is no longer just a piece of software, but a global community project with thousands of users and contributors.
Two ways to use the system
You can use the software in one of two ways: either as full autosteer, where the tractor steers itself, or as a visual guidance aid (often called a “lightbar” in the AgOpenGPS community), where you steer yourself.
Software and hardware
The software consists of two parts that work closely together. AgOpenGPS is the guidance and mapping program you see on the screen. In the background, a second program, AgIO, handles communication between the GPS, the sensors, the hardware and the screen in the tractor. The software runs on a tablet or laptop in the cab.
The actual steering is done by hardware the community has developed together: a steering motor on the steering wheel (or a steering wheel with a built-in motor), a wheel angle sensor on the front wheels, a tilt sensor for terrain compensation (read more about the IMU) and a GPS receiver. With RTK correction, a high-precision positioning service, accuracy gets down to just a couple of centimeters, pass after pass.
The system supports several guidance patterns, including straight AB lines, curves and contour driving. It can also handle automatic U-turns on the headland. On the implement side, section control and rate control give you better control over where and how much is applied.
What it costs, and what you own
Commercial autosteer systems typically start at around NOK 75,000 and go well up from there. Many of them also rely on annual subscriptions, for example for the correction signal itself, or to unlock features on a system you’ve already bought the hardware for. With some brands, every feature has to be activated for a fee, and if you switch brands or dealers, you may have to start over. In practice, you’re renting your way into a system you never fully own. AgOpenGPS turns this entrenched model on its head: the software is free, the code is openly available, and you own the system 100%. There are no subscriptions or lock-ins tying you to a single supplier, and you can repair, upgrade and customize the system for as long as you like.
Open source also means that improvements made by one farmer benefit everyone. Bugs get fixed quickly, new features are shared freely, and the project develops in step with what farmers actually need out in the field. Because the hardware is built from affordable, widely available components, precision technology becomes accessible even to farms where a commercial system would never make financial sense.
More than saved diesel and inputs
An autosteer system also has far more benefits than just saving diesel and inputs. Most farmers who start using it say their days in the field become much more comfortable. When the tractor steers itself, you no longer have to stare at a fixed point on the horizon hour after hour, and can focus instead on the implement and on making sure the job is done properly. It’s less tiring for you as the operator, and you can handle longer shifts without being completely worn out. You can also work precisely when visibility is poor, at dusk, in the dark, in dust or fog, because the steering no longer depends on you seeing your own tracks. And because the system drives just as accurately every time, no matter who’s in the seat, the result is just as good whether it’s you or a new relief driver behind the wheel. If you also drive in fixed tracks year after year, soil compaction stays in the same wheel tracks instead of spreading across the whole field, which is better for both yield and soil structure. Straight, accurate passes also make all the follow-up work easier, from inter-row cultivation to harvest.
A global community
AgOpenGPS has an active international community that shares build guides, hardware designs, experience and troubleshooting. The project has its own documentation site and discussion forum, where beginners and experienced farmers alike help each other out. It’s this community that has taken a one-man project from a farm in Canada to steering tractors on every continent.
How to get started
AgOpenGPS can be a valuable tool for almost any farmer, but someone has to put the parts together, wire them up correctly and configure the system for your particular tractor. That’s where this site comes in. The goal is to make the path from curious to a fully autosteered tractor, combine or other farm machine as short as possible. You don’t need to be a programmer or a software engineer. With detailed build guides, well-considered component choices and in-depth articles, you get the help you need to get started on your own. And if you’d rather skip straight to driving than build everything from scratch, I also sell complete kits ready to install. Wherever you choose to start, the idea is the same: to make precision farming accessible to ordinary farms, without commercial price tags and lock-ins.
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