# Automation and Robotization of Underground Mining in Poland
## 3 Research and Development in the Field of Robotization of Mining in Poland
### Autonomous Machine for Breaking Rocks  
The most important elements of the ore mining process have been presented earlier. In this process, the mined rock from the face is transported to the surface. The transport system includes non-continuous haulage to handling points, also referred to as transfer points, where the mined rock is loaded onto conveyor belts. Large lumps of mined rock can damage the conveyor, so the handling points are fitted with grates mounted by means of manipulators with hydraulic hammers. The operator manipulates the boom to clear the grate of mined rock in the quickest possible way. The operator is exposed to many adverse factors. First, a hammer remote control followed by an autonomous machine were developed and installed. The project was implemented by the consortium composed of KGHM ZNAAM S.A., AGH University of Science and Technology and KGHM CUPRUM Sp. z o. o. (Wroclaw, Poland). Research and Development Centre [14; 15; 16]. The main goal of the project was to develop an automatic grate cleaning system. Constructing an autonomous machine required equipping it with an automatic control system, which, based on information from a number of sensors, would react to changes in the environment and generate control signals in such a way that the main goal, i.e., the cleaning of the grate, could be achieved. The main element was a hydraulic boom with a hydraulic hammer attached at the end. The boom has 4 degrees of freedom. An analysis of the functioning of the existing manual system was carried out and consultations with future users of the transfer points were held. The conducted analyses enabled specifying the tasks to be performed by the machine. the most important restrictions and requirements formulated in the form of the following assumptions. The control system should operate in an autonomous manner. * The operator can take over control at any time and turn off the autonomous system. * At least 80% of activities related to rock crushing will be performed by the machine automatically. * The operator interfering with the situation on the grate 20% of the time. * The process of clearing the grate of mined rock will last up to several minutes. * Constructional changes must be as small as possible in relation to the existing equipment. The system is, among other things, equipped with hydraulic cylinder sensors and a mined rock heap scanner. The system was installed at the test stand at KGHM ZNAAM S.A. (Figure 7). The stand was designed and constructed in a manner enabling its use in the underground mines of KGHM Polska Miedz S.A. The device should be adapted to work in the following conditions:  
* Relative humidity up to 95% at a temperature of up to + 40 \({}^{\circ}\)C
* Degree of corrosive aggressiveness--C according to PN-71/H-04651
* Maximum relative humidity at a temperature of + 25 \({}^{\circ}\)C or at lower temperatures with 100% steam condensation. The remote-controlled stand is monitored by cameras. It has been equipped with optical barriers and signaling devices to supervise and ensure traffic safety in the vicinity of the grate. The automation system controls the boom by means of signals determined by the current state of the system and the setpoint. This system consists of a master control layer and a direct control layer. In the superior layer, after identifying the shape and dimensions of the mined rock heap is identified (Figure 8). The control system generates a trajectory that will be implemented by the direct control system. The trajectory was developed using heuristic algorithms and observations of the grate cleaning process. The automatic control system consists of four main modules: mined rock identification, determination of hammer motion trajectory, inverse kinematics and direct control. After being equipped with a shape identification assembly, the device becomes a robot, which autonomously detects the position of mined rock on the grate and, then, starts removing it.