Studies of behaviour of the automatic control system of roadheader cutting heads movement

Boom–type roadheaders are basic machines used in underground mines for drilling roadways, in tunnelling and also for making underground buildings using trenchless methods. The article presents selected results of tests carried out in a semi–industrial scale, on a roadheader R–130, concerning behaviour of an innovative solution of system for automatic control of boom–type roadheader cutting heads’ movements. This important innovation, not known before in mining cutting machines, is the software control of cutting heads angular speed using a frequency converter. The text shows an impact of key values, from a perspective of an assumed control purpose, of programming device (setting system) parameters, achieving reference values for the actuators, on controlled facility behaviour when cutting a layered cement and sand block. The performance of the automatic control system without and with feedback to the setting system concerning an actual speed of cutting heads movement, which is important from the control system hardware perspective, was compared.