u-blox F9 high precision GNSS module
15 Jul 2022
How a group of tech-savvy farmers are using open source technology to reap the fruits of precision farming - and making it available for farmers around the world.
Fuel and fertilizer prices are at all-time highs, and farmers around the world are scrambling to find ways to maintain the profitability of their operations. Large commercial farms are leveraging AI and cutting-edge hardware to plan their operations and automate tasks. Broad networks of sensors to monitor soil quality, drones using computer vision to monitor crop health, and autonomous tractors are all tools that are being utilized to vastly improve efficiency. However, these systems can be prohibitively expensive, and their costs are hard to justify for smaller farms. The vast majority of the world’s 570 million+ farms are smallholdings: farms less than two hectares in size. Many of these farmers don’t have access to capital to invest in new equipment, and heavily rely on older machines and human labor. To help bridge the gap in precision agriculture technology and make it more accessible to more farmers, a community of farmers is contributing to a project called AgOpenGPS to take on some of these challenges using affordable open-source technology.
Driving in a straight line may seem like a simple task, but when you are operating a tractor for hours on end without any guidance equipment, all those minor deviations over each pass add up to increase resource costs. Farmers would traditionally use clay disks at each end of the field to create virtual lines, which they would follow for their first pass. Subsequent passes follow the previous edge, but depending on the type of equipment being used, vision can be limited, and handling can be rough. You really have to rely on your peripheral vision while controlling several other systems simultaneously. Guidance systems similar to your mobile phone’s navigation app have been used to help provide operators with real-time feedback on their position, and the latest systems enable full autonomy with auto-steering. AgOpenGPS seeks to solve this by using GPS, optionally fused with additional sensor data, to automatically steer a tractor. The solution can maintain a pass-to-pass accuracy down to a few centimeters, performing automated turns and intelligently controlling the feed rate of seeds or fertilizer. All without manual intervention of the operator.
AgOpenGPS (AOG) started as an open-source auto steering-solution created by Canadian farmer and software developer, Brian Tischler. Brian was frustrated with the proprietary nature of commercial solutions, so he created his own. AOG delivers a complete auto-steering solution including hardware design files, real-time microcontroller firmware, and software that runs on a PC, which can be used by anyone who can handle a soldering iron and knows some basic programming. The project requires some tinkering based on the type of equipment that is being automated, but AOG community combined has invested thousands of hours into making the platform accessible to the masses. Some farmers have rigged up motors to their steering wheels instead of tapping into the electronic control systems. Others have spent hundreds of hours reverse engineering communication protocols to tap into modern tractors.
Jake, a farmer and machinist, is one of many contributors who uses his free time to work on the AgOpenGPS project. He’s not an electronics engineer by trade, but he taught himself how to design and manufacture printed circuit boards and has been a part of the team that developed an all-in-one AgOpenGPS auto-steering controller. Jake has reaped the benefits of auto-steering systems for years and is committed to providing accessibility of this technology to farmers who can’t afford the expensive commercial systems. Retail auto-steering solutions can cost anywhere from $5,000 to $30,000+ to install, while the cost to build an AOG system starts at about $700. One of the farmers who he helped install auto-steering equipment initially had an annual fertilizer spend of $100,000. In their first year of implementing the system, they saw a 20% reduction in consumption. “Some Farmers running OpenAgGPS have retrofitted tractors that you wouldn’t even find at an auction. I’m talking about farmers in developing countries who are using tractors from the 1960s that are covered in rust, yet they are realizing that with an investment of about $700, they can make that money back in one season.”
Jake says while there are many economic benefits of auto-steer equipment, one very important factor is reducing operator fatigue. Before using auto-steer, his hands would be cramping up after a long day of work, and he would be physically drained. This is no longer an issue for him as he can now focus on what his equipment is doing instead of fighting to keep it in a straight line for hours on end.
Commercial autosteering kits are available today for all types of vehicles, whether they require aftermarket installation, or are provided as a premium option from OEMs, but these solutions come with quite a few challenges. To achieve centimeter-level pass-to-pass accuracy, the GNSS receivers used in precision solutions rely on what is called GNSS correction data. This is a stream of data that the receiver can use to improve its accuracy from meters down to centimeters. How this data gets to the receiver, how much bandwidth it consumes, and how much it costs to implement pose additional costs in implementing these systems. Today, these rely on a range of wireless communication methods to stream correction data to vehicles. Farmers can deploy a local base station that is used to monitor environmental conditions and generate the correction data. This data is then transmitted to the vehicle via ISM band radios, Wi-Fi, or long-range Bluetooth radios. Satellite-based receivers are also available but typically come at a high price as both the hardware and data costs are expensive.
AOG solutions are leveraging the u-blox ZED-F9P and ZED-F9R centimeter-level positioning modules to provide the system with reliable and accurate position data. These modules provide survey-grade accuracy at a price that is scalable for mass-market adoption, enabling projects such as AgOpenGPS to provide an affordable solution to farmers globally. ZED-F9R integrates an inertial measurement unit (IMU) and a wheel tick input to perform integrated sensor fusion, improving performance in areas with high multipath reflections such as near trees or structures. The ZED-F9P can be configured as either a standalone rover, providing positioning data to a tractor, or as a base station to generate local corrections over a radio link. The additional costs and complexities of installing and managing local bases station are reasons to consider an SSR-RTK-based system.
With precision ag use cases in mind, u-blox has launched PointPerfect, a continental SSR-RTK correction stream enabling scalable precise positioning in the continental US and Europe, with additional markets coming soon. With SSR-RTK, there is a single correction stream for the entire continent, compared to a local base station where it can only provide corrections for up to 10 kilometers. No base station is required to be installed, as the corrections are delivered via either IP or a satellite connection. Installing a base may not be an issue for farmers who have the supporting infrastructure, but PointPerfect is a great alternative where a local base is not feasible. The most common communication methods used to receive PointPerfect corrections are either via local cellular module such as the u-blox LARA-R6 Cat-1 cellular modem or via satellite using the u-blox NEO-D9S L band receiver. The satellite-based option is a great fit for use cases where internet access via Wi-Fi or cellular connectivity is not available.
Access to affordable centimeter-level positioning is enabling use cases such as auto-steering and autonomous lawn mowers. Farmers in developing markets have not had access to technological advancements in agriculture, and productivity continues to remain low. In many markets, decades-old equipment is still in operation. OpenAgGPS can support almost any tractor with some minor modifications, which could result in a revolution in productivity with minimal investment. These solutions can free up resources for farmers to perform other responsibilities that can have more impact on their business instead of the traditionally dull and dangerous tasks.
The AOG community is continuing to work on next-generation solutions to help farmers around the world have access to technology that will help boost their productivity and grow their businesses. The AOG community has grown to over 2500 members, who are continually improving the functionality and accessibility of the project.
u-blox has a broad portfolio of GNSS, cellular, and short range radio modules, as well as correction and communication services that enable mass-market adoption of autonomous solutions.
Regional Application Marketing Manager, Americas, u-blox