Control the lighting from the High Tech Campus or set the watering for the grass cover about 120 km away, in the Johan Cruijff ArenA. It may sound illogical, but that is exactly what the databiologist Joep van Cranenbroek has made possible. The Eindhovens Dagblad has written an article about how this is possible. The interview was so cool, we decided to publish the translated version, but you can check the original in Dutch here.

Watch over Ajax grass from Eindhoven

EINDHOVEN – During the entire thrilling title battle of this season, Ajax benefits from the finest grass. And all thanks to a watchful eye from Eindhoven, from a databiologist from Budel.

Merlijn van Dijk 13-04-19, 07:30 Source: ED

No, it is not that Joep van Cranenbroek can switch on the Johan Cruijff ArenA spraying system at the touch of a button during, grab it, Ajax’s match against Excelsior on Saturday evening. But it doesn’t matter much. The Budel data biologist monitors the Amsterdam grass from the High Tech Campus in Eindhoven.

Van Cranenbroek (28), who works for Holland Innovative, continuously receives data on his laptop. The data comes from the field in the ArenA, about 120 kilometers away. A complete system of sensors ensures that the biologist can monitor the grass at all times.

If necessary, he gives instructions to the grass team in Amsterdam. A little more light here, some extra water there. It already earned him the nickname ‘databiologist’. He even has access to a webcam that films the field. “Look, there is my weather station network,” says Van Cranenbroek from Eindhoven. He points at his laptop. “If the data shows that there is something wrong with the field, I will first look at the field via the webcam.”


So to the blades of grass. Because he doesn’t really care much about the game itself. He works for the ArenA and not for Ajax, Van Cranenbroek emphasizes. “Ajax is an important user of the ArenA,” he says. “But it is also important that the ArenA can organize major events.”

For example, the Irish rock band U2 performed, in 2017. Ajax played another match within 67 hours of the show. Based on Van Cranenbroek’s data system, the ArenA can determine whether the grass can survive such a large concert, and therefore the grass is covered, or whether a completely new mat is needed. And when a new field is laid, Van Cranenbroek walks around to put his 12 sensors in the right place under the turf.

Understand the data

These sensors measure the temperature, humidity and nutritional content of the grass. Van Cranenbroek also receives information from a number of weather stations and sensors in the lawn mowers, which measure how fast the grass grows. After each match, he also receives feedback from the football players. 

He has also charted how much sun the grass gets. It turns out that one blade is not the other. Because of the roof of the ArenA, some blades get more sun than others.

He receives all that data through his laptop. It is up to the Budelnaar to interpret the data: “I give meaning to it.” Van Cranenbroek is not patting himself on the back, but the fact is that the grass in Amsterdam is only replaced once a year, whereas previously that was three times a year it makes him proud. The field is also no longer slippery. What if PSV calls and wants to hire him? “Then I would first have to consult with the ArenA.” His system is in principle the property of the people of Amsterdam. But don’t worry: the KNVB [Dutch Soccer Organization] is investigating whether the data system can also be used at other clubs.