Slow but steady robots take to the field

January 28, 2022 - By Matteo Luccio

Photo: Advanced Navigation

Intelligent navigation-based automation is redefining the farmer’s humble tractor to robotic status. This results in significantly faster field preparation and cropping and dramatically reduced labor costs.

Any autonomous vehicle requires the highest levels of navigational accuracy, control and safety. For farming applications, this typically means maintaining exact heading at very low speeds, often over bumpy terrain. These requirements make using the right navigational equipment critical to success. The key challenge is maintaining precise placement and movement of the tractor relative to crop rows and field boundaries. Failure to maintain precision can cause rows to be damaged or planted seedlings to be uprooted. The typical accuracy required for precision farming is position to within a decimeter (10 cm) — well beyond basic GNSS. This requires real-time kinematic (RTK) positioning and advanced signal processing.

Sabanto, a U.S.-based farming as a service (FaaS) start-up, was facing this exact challenge. The company needed a precise and reliable navigation solution for its fleet of driverless tractors deployed in a growing number of U.S. states, including Illinois, Iowa, Nebraska and Minnesota.

“The reliability of Advanced Navigation’s GNSS Compass gave us the peace of mind required to operate fully autonomously from Spring to Fall of 2020,” explained Craig Rupp, CEO of Sabanto.

Thanks to its dual-antenna GNSS and RTK corrections, the GNSS Compass can offer high-accuracy heading. Accurate position is maintained using real-time correction data, delivered from nearby ground base stations, resulting in near-centimeter accuracy under the most demanding conditions.

Furthermore, the GNSS Compass includes an integrated inertial navigation system (INS) to ensure consistent position accuracy of the tractor in the event of degraded or lost signals from GNSS satellites from heavy canopy or steep terrain. Roll, pitch and heading data also improve the stability of the autonomous platform over difficult terrain.

Sabanto engineers can now deploy and remotely monitor their fleet of autonomous tractors 24/7. Operators can simply pre-program the itinerary and field boundaries, as well as when to lift and lower tillers, resulting in the tractors planting up to two hectares (five acres) per hour.