In order to continuously perfect the Oz weeding robot, Naïo’s engineers have now tackled a key issue for agricultural robots, i.e. work autonomy. Autonomous agricultural robots, like Oz, that can weed by themselves for 3 hours straight are already a great accomplishment. However, after months of work on the integration of more effective batteries, the Naïo Technologies R&D team has now managed to increase the robot’s autonomy to 10 hours non-stop, thanks to lithium batteries.
When Oz first started out, the robot worked on lead acid batteries. These could only be recharged 200 times maximum and were unable to discharge completely, resulting in a relatively short battery lifespan. The batteries also weren’t watertight, which created safety issues during manipulation. As the batteries only lasted for 3 hours, market farmers often had to use a succession of rechargeable batteries to get the work done. This required repeated manipulation and an increased safety hazard due to the batteries’ liquid acid components.
The second version of Oz works on AGM 80 A/h batteries, which also contain lead and acid but are completely safe for human use. The robot’s autonomy is similar to the first version but the battery’s life span has sensibly increased due to the integration of a BMS (Battery Management System) card. The BMS card stops the battery from discharging completely and sends a warning to the farmer when discharge is imminent. Today, this version of Oz is still in use as it is well adapted to small market farms that don’t require more than half a day’s work.
For larger farms, a new era has arrived with the lithium battery 100 A/h. This new battery allows to triple the autonomy of our beloved Oz and can be recharged up to 2,500 times, i.e. about 10 years (against 1 year for the AGM 80 A/h battery). What’s more, the lithium battery doesn’t contain acid and is therefore completely safe for human use. The battery is self-regulating and will prompt Oz to continue weeding as long as the battery isn’t fully discharged. This feature allows Oz to give very reliable indications on the time spent in a plot. Farmers can now have Oz work in the field all day (instead of half a day) in order to weed and hoe larger vegetable plots and fields.
Thanks to the hard work of our R&D team, customers now have the choice between two different batteries depending on their needs. For small market farmers, the AGM battery will be amply sufficient. However, if your farm exceeds 25km of rows, your best option would be the lithium battery.
In the future, the increase in battery autonomy will also allow us to adapt so-called active tools to our Oz weeding robot, so don’t forget to check our news regularly to monitor our progress.
