Development of a control system for a multipurpose road repairing machine

In this paper an automatic control system for a multipurpose road pavement repairing machine (ROADMOTO) is introduced. ROADMOTO machine is equipped with asphalt milling drum and two asphalt spreaders. The old wearing course of the road is heated and milled. Asphalt spreader in the middle of the machine is used for spreading the crushed old pavement. Asphalt spreader in the back of the machine is used for spreading the new asphalt mass on top of the old layer. Until now most functions of the machine have been manually controlled. The goal is to achieve cost saving and better work quality by using automation. Before the actual repairing work a GPR (Ground penetrating radar), a profilometer or laser scanning techniques are used for collecting information about the road. Designing of repairing tasks is based on the collected data. During a design phase a repair design file is created. ROADMOTO machine is equipped with a GPS positioning unit and the repair design file can be used for automatic control of road repairing operations. The control system also offers a manual control mode as well as automatic height and slope control modes. This ensures flexibility, because the user can choose control mode that best suits for the situation. The control system uses CAN bus as sensor and valve interface and hydraulic actuators are closed loop controlled to achieve high control accuracy. The concept from the data collection and design to the automatic machine control is presented as well as the developed prototype system and results from the first tests