Study of a weight balancing system for an agricultural robot

Nowadays the agricultural sector is developing new technologies to help farmers to make their work simpler. Mainly in the forestry sector the new machine that is becoming more popular in these years is the robotic tool carrier that can be used in a large variety of works. The goal of this thesis is to create a system capable of reducing the soil compaction of a robotic tool carrier. The machine that is studied in this thesis was built by the ALPIrobot an Italian company located in Bagnolo Piemonte(CN), and is basically composed of three parts: the motor block, the chassis and the tool on the front. This type of 'tractor' are meant to work on rough terrain and should reach very high inclination. The first thing to do is study the weight distribution of the machine when the machine work on inclined terrain. To reduce soil compaction the objective is to have the most possible uniform distribution of the weight. To do so we created a system capable of moving the motor block and capable of balancing the slope of the terrain. This will allow to have half of the weight on each track. To move the motor I need first of all to know the inclination of the terrain that is measured with sensors, then through a PLC ,the machine will execute a code, written using CODESYS, that drives some valves and then move the motor in the place needed thanks to two position sensors. All the communication are handled by the PLC that also provide a CAN interface which simplify the communication with some sensors. Finally are calculated some important working limit angles, over which the machine have the risk to turn over. In conclusion we tested the machine, first in a safe ambient in order to see if everything worked correctly, then on very rough terrain and it worked as we expected. The machine goes on almost every terrain thanks to its tracks and reach important slopes without any sign of roll over.