UUDISED

GOOD PROJECT EXAMPLE: Development of a Soil Sampling Automation Device

 The problem to be solved

Collecting data on soil parameters is time-consuming and the collected data might not be accurate. In Estonia, soil samples are collected with the purpose of assessing soil fertility and observing changes in the soil. Soil samples are collected every five years. For the collection of soil samples, a field is divided into approximately 5-hectare test sites – the test sites should be of as uniform texture and soil type as possible. A followed trajectory is marked on the test area while collecting samples.

Soil samples are collected along the trajectory and should be taken from the plough layer. Soil sampling involves the collection of 20 to 30 soil cores within one test area. About 500 grams of soil should be collected from one test site to be sent to the laboratory for the analysis of the content of the nutrients in the soil. In order to get comparable data over the years, it is important to do the preliminary work precisely and accurately. Only this way it is possible to get data, which can be used for making conclusions and decisions.

The main objective of the project was to develop a robotic soil sampling device. The unmanned device follows the trajectory of the test site and measures the density of the soil, which is an important physical parameter and its value should be known for the selection of suitable cultivation methods. 

Project outcomes

The purpose of the soil sampling device is to collect soil samples and information about the physical properties of the soil at the same time. The collected samples are stored in a module inside the tractor, thereafter the samples are taken to the laboratory where the chemical properties of the soil are analysed. The soil testing equipment has also a penetrometer for the collection of information about the physical properties of soil, such as soil density. Knowledge about soil nutrient ratio, soil texture and the physical properties of the soil enables us to make decisions, which are environmentally sustainable and ensure the efficiency of production.

The taken sample gives information about soil density, the data on the collected sample is saved in the head module of the tractor.From the module, the sample moves to the test box inside the tractor. After completing the task, the tractor moves on to another soil testing point. The power mechanism is in the other module inside the tractor. The petrol engine is the power mechanism with the function of starting the hydraulic pump, which enables to move the machine and the collection of samples.

“Today soil samples are in most cases taken by people; however, a robot is more precise than a human and makes fewer mistakes.” Henri Lehiste, the project leader