Test with Robot One from Pixelfarming at Dutch bulb grower

Dutch grower Ruiter is looking for possibilities for far-reaching minimization of the use of herbicides in his tulip cultivation. He wonders what the Robot One can do for him. The starting point is that not everything that is not a tulip has to die.

Recognition of tulip

In the first instance, the question is whether the cameras are sufficiently capable of recognizing individual plants in a bed of tulips. If each independent plant is detected as such, this is sufficient to teach a recognition algorithm to name them. The next step is to instruct a tool under the robot to remove unwanted plants. In principle, this can be done in different ways: spraying a little herbicide on it with a selector, mechanically (push it into the ground or mill it out or pull it out) or, for example, remove it with a laser.

“Detection is the biggest challenge in this”, says Koen van Boheemen of Wageningen University & Research (WUR), who assists Stef Ruiter from the National Experimental Garden for Precision Agriculture (NNPL). “If the detection is good, there are several ways to view the unwanted plants. It is then a matter of looking at what performs best.”

More reduction of herbicides

Stef Ruiter: “The use of herbicides in the cultivation of flower bulbs has already been significantly reduced through various studies and systems. With this technique, another nice reduction step can be taken. The soil in which the bulbs are planted in November remains black until February and must be kept free of weeds.” But, Ruiter argues, not every weed plant has to be removed. Plants that do not bother him or that are useful and can even be sown as a bottom crop (nitrogen fixation) must remain. On the other hand, strongly rooting weeds such as pig grass and cultivated grass must be dealt with. The roots grow through the nets and make harvesting more difficult. Ruiter grows his tulips on beds between fixed paths, the spores of which are 1.82 meters apart center to center.

Recognize and label plants

The Robot One has now been sent into the country in Andijk to see whether the cameras collect sufficiently sharp images. Sharp enough to be annotated or labeled by human or computer; provide the individual plants with the correct ‘names’. That is the basis for later removal or not.

Pixelfarming Robotics supplies the robot and the associated software, the customer can then develop his own recognition algorithm. With the help of the software, the grower can train the computer himself, feed it with knowledge of whether or not plants can be tolerated.

Lots of potential

Stef Ruiter sees great potential in the technology to drastically further limit the use of herbicides in his bulb cultivation. “If it works, compared to the cost of man hours, the investment of € 250,000 is not insurmountable in itself,” he said at the beginning of March during a presentation by Pixelfarming Robotics.

Van Boheemen of WUR is curious about what the images look like. “Success is not yet guaranteed. This is not a crystallized technique that you purchase and that you can use immediately. You are entering a trajectory of a few years. A very decisive factor is how well you succeed in labeling the images with a minimal chance of errors. You don’t do that for a while.”

_{Text continues below picture}

Camera controlled hoe

Another experiment was with a camera-controlled hoe from Steketee, two days later. To test hoeing, Ruiter had planted the last part of the tulips in rows last autumn. Somewhat provisionally, he made some adjustments to the planter with some welding.

Although the rows weren’t perfectly straight and the camera was sometimes confused by the occasional stray tulip, the Steketee sideshift hoe did a decent job. A condition for this approach is the conversion of the cultivation system from broad beds on beds to seven rows of tulips on beds.

Compared to the robot with cameras, recognition algorithm and arms to tackle weeds, the camera-driven weeder in 2023 is a machine that has already proven itself in various crops. You can get started with it.

Even so, Stef Ruiter is very interested in what the Robot One can bring him. If the weed control works, perhaps the next job is to search for diseases, for which the device can be used.​