Piotr Gierlak

Rzeszów University of Technology · Department of Applied Mechanics and Robotics

This article focuses on the implementation of an approximate dynamic programming algorithm in the discrete tracking control system of the three-degrees of freedom Scorbot-ER 4pc robotic manipulator. The controlled system is included in an articulated robots group which uses rotary joints to access their work space. The main part of the control syst...

In this article, we discuss the detection of damage to the cutting tool used in robotised light mechanical processing. Continuous monitoring of the state of the tool mounted in the tool holder of the robot is required due to the necessity to save time. The tool is a brush with ceramic fibres used for surface grinding. A typical example of damage to...

The paper presents the issue position/force control of a manipulator in contact with the flexible environment. It consists of the realisation of manipulator end-effector motion on the environment surface with the simultaneous appliance of desired pressure on the surface. The paper considers the case of a flexible environment when its deformation oc...

At present, every branch of industry is characterised by high process and system complexity. The reliability and quality of system operation with the simultaneous multi-criteria optimisation of processes to ensure the effective use of technical and material resources, etc., is a key element in building a competitive economy and gaining an edge over...

This paper deals with the analysis of nonlinear vibration phenomena in the arm system of an industrial robot. The presented mathematical model of the robot takes into account the flexibility of the joints, which results in low-frequency vibrations in the arm. The study of vibration phenomena has been carried out using analytical, numerical and expe...

Vibration analysis of industrial robots is one of the key issues in the context of robotisation of machining processes. Low-frequency vibrations result from flexibility in manipulator joints. Within the scope of the article, a model of a two-link robot manipulator was built. Dynamic equations of motion were formulated to study the influence of the...

This article presents the synthesis of a neural motion control system of a robot caused by disturbances of constraints limiting the movement, which are the result of flexibility and disturbances of the contact surface. A synthesis of the control law is presented, in which the knowledge of the robot’s dynamics and the parameters of a susceptible env...

The impulse for writing the paper is the observation of the works related to the implementation of robotization of processes such as machining, glue application, welding and painting. The abovementioned processes, in addition to the correct implementation of the trajectory, require the definition of various parameters (e.g., speed) in the robot’s s...

The aviation industry is associated with high precision and accuracy standards of the manufactured components, and thus the need to ensure precise quality control. Measurement processes, depending on the manufactured components, take place before, during and after the processing stage. Optical scanners can be used for these measurements, the measur...

The subject matter of the above paper presents part of the research carried out as part of the robotization of the manufacturing processes of aircraft engine components. The paper concerns robotic deburring of the V2500 diffuser’s sharp edges. The diffuser is a precision casting characterized by a slight variation in the geometry of the workpiece d...

This paper presents the use of a laser tracker for programming paths of industrial robots. The idea of operation, application, and the offered accuracy of the laser trackers are discussed. Then, the developed method of using a tracker for determining the path points of an industrial robot is presented. The requirements related to the developed meth...

This paper deals with the development of dimensional control technology for the production of accessory drive train (ADT) gearbox housing, according to the closed door technology approach. The work presents the methodology of the final inspection of bearing seat position deviation by replacing the coordinate measuring machines (CMMs) with a compute...

The development of industrial robotics requires the use of increasingly sophisticated control algorithms. In modern tasks posed by industry, it is not sufficient for the manipulator to move along a programmed path, reaching individual points with the greatest accuracy. There is a need for solutions that can allow detection and avoidance of obstacle...

The aim of this article is to present an overview of the most important robotic processes in which force control methods are applied. In recent years, robotization has seen a rapid increase in the use of industrial robots in tasks that require simultaneous implementation of a given path of motion and the robot's force of interaction with the enviro...

This paper discusses the stability of systems controlling patient body weight support systems which are used in gait re-education. These devices belong to the class of underactuated mechanical systems. This is due to the application of elastic shock-absorbing connections between the active part of the system and the passive part which impacts the p...

The article discusses the quality testing of a measuring system consisting of a CNC machine with measuring probes. The research was conducted in a broader context regarding the implementation of the closed door technology, i.e., production without human intervention, in an aviation plant manufacturing aircraft gearbox systems. This technology may i...

The present paper concerns the synthesis of robot movement control systems in the cases of disturbances of natural position constraints, which are the result of surface susceptibility and inaccuracies in its description. The study contains the synthesis of control laws, in which the knowledge of parameters of the susceptible environment is not requ...

This article concerns the stability analysis of a control system for a dynamic body weight support system in a rehabilitation device for the re-education of human gait. The paper presents a physical model of the device, which characterizes the most important physical phenomena associated with the movement of the system, i.e., inertia, damping, and...

The article discusses the design, implementation, and testing of the accuracy of a measuring device used to measure the thickness of aircraft engine blades subjected to a robotic grinding process. The assumptions that the measuring device should meet were presented. The manufactured device was subjected to accuracy and repeatability tests using a s...

The article presents an original method of communication and data exchange in a robotic machining station consisting of two robots, a positioner and a 3D optic scanner. The task of one of the robots, equipped with a 3D optic scanner, was to receive point cloud of a detail (mould) attached to the positioner table. After detail digitalisation, the re...

The development of software applications and the use of VR (Virtual Reality) techniques allow to improve the company’s financial result. The construction of models of robotic stations with robots using Virtual Robot technology allows to determine the time of the machining process. It allows its optimization through the selection of accelerations, t...

The article presents a method of programming robots using virtual reality and digital twins. The virtual environment is a digital twin of a robotic station, built based on CAD models of existing station elements. The virtual reality system is used to record human movements in a virtual environment, which are then reproduced by a real robot. The met...

The article deals with the selected aspects of quality control of aircraft accessory drive train bodies. The work presents the concept of control of selected dimensional and shape characteristics. The key issue under consideration is the possibility of replacing the coordinate measuring machines (CMM) in selected measuring operations with a compute...

The article discusses the subject of the use of virtual reality in training the service and maintenance of robots and robotic stations. The developed trainings use virtual reality, thus they are interactive and allow advanced operations without the risk of damaging expensive equipment. The idea of the training program and the application of virtual...

The article presents the subject of the practical application of virtual reality in the design and programming of robotic stations. Robotic stations designed with the use of virtual reality were created in a collaborative network study consisting of a university, enterprise and government organization - National Centre for Research and Development....

This paper presents the design and construction of a module for measuring the geometry and orientation of turbojet engine blades. The measurement module forms a component of a robotic processing station for grinding of turbojet engine blades. The robotic processing station comprises an industrial robot manipulator with a dedicated gripper, the meas...

This paper presents a method for the robot-assisted geometric inspection of an aircraft engine turbine stator segment, involving two robots. The first robot was an ABB IRB 1600 with an optical 3D scanner. The second robot was an ABB IRB 140, to automatically inspect the stator vanes at 168 points by the application of a UTT method. If the casting g...

The article presents two commercial tools used to monitor the parameters of robot operation. They are briefly characterised, and their advantages, disadvantages and limitations described. The indicated shortcomings led to the development of a proprietary program, which allows for monitoring the parameters of ABB robot operation. The application’s t...

The paper presents the problem of eliminating the effects of inertial forces on the measurement circuit of the forces of interaction between a robotic manipulator and its environment. Inertial forces are among the most significant interferences in force measurement circuits. The causes and effects of this interference type are discussed. A concept...

This paper presents a design, a numerical analysis, a build-up and dynamic testing of an engineered and fabricated wheel with a passive vibration damping system designed for a roller coaster system. Taking into account the limited amount of space for fixing a wheel to a roller-coaster, this study shows an approach in which a special wheel design an...

The article discusses the question of a combined strategy for control of interaction force between a manipulator and a flexible environment, aimed at conducting robotized machining of surfaces of disturbed shape, taking into account their flexibility. The control strategy combines, on the basis of competitiveness, two elementary control strategies....

The article presents the methodology of body vibration analysis of an inspection robot with the use of flexible connection between the body and the track propulsion modules. The article presents the methodology of selection of motion parameters of an inspection robot, taking into account the vibration of the robot body. The speed of movement of the...

The subject of the article is the adaptive position and force control of a robotic manipulator in interaction with flexible environment. The aim of the study is to provide a solution that takes into account the essential aspects of operation of the manipulator with the environment and at the same time can be actually implemented. A manipulator–envi...

This article presents a method of processing and analyzing the measurement signals used in the problem of diagnosing the state of a manipulator's tool. The analysis of the signals was performed within the domain of time and frequency. The signals utilized in the analysis were the mechanical vibrations and the rotation speed of the tool. The databas...

The issues presented in the article, relate to the detection of damage of a cutting tool used in robotised machining. Due to the time saving requirements, it is desirable to carry out the current control of the tool mounted in the holder of the robotic manipulator. The tool is a ceramic fiber brush used for grinding. A typical damage of the brush i...

The article presents an application of the hybrid neuro-fuzzy system in the task of position-force control of a robotic manipulator. The position-force control is especially important when the interaction force between the manipulator and its environment are large. This control problem relies on simultaneous execution of interacting forces between...

The article focuses on the implementation of the globalized dual-heuristic dynamic programming algorithm in the discrete tracking control system of the three degrees of freedom robotic manipulator. The globalized dual-heuristic dynamic programming algorithm is included in the approximate dynamic programming algorithms family, that bases on the Bell...

In this paper, a mechanical imbalance prediction problem for a milling tool heads used in Computer Numerical Control (CNC) machines was studied. Four classes of the head imbalance were examined. The data set included 27334 records with 14 features in the time and frequency domains. The feature selection procedure was applied in order to extract the...

This paper presents an application of a robotic manipulator in a machining process. Due to the specifics of the process and numerous phenomena which are difficult to be modelled, suitable tool for the robot control are neural networks. This work concentrates on the robot control process. A synthesis of a neural position/force control algorithm is p...

In this paper, to solve the problem of control of a robotic manipulator’s movement with holonomical constraints, an intelligent control system was used. This system is understood as a hybrid controller, being a combination of fuzzy logic and an artificial neural network. The purpose of the neuro-fuzzy system is the approximation of the nonlinearity...

This article presents an application of the hybrid position-force control of the robotic manipulator with use of artificial neural networks and fuzzy logic systems in complex control system. The mathematical description of the manipulator and a closed-loop system are presented. In the position control were used the PD controller and artificial neur...

The article presents an application of the neural hybrid position/force control of the robotic manipulator. Realisation of many machining processes requires an application of the hybrid position/force control in order to perform the desired robot trajectory, which results from the machined surface geometry, and the desired tool downforce. The appli...

The problem of the manipulator hybrid position/force control is not trivial because the manipulator is a nonlinear object, whose parameters may be unknown, variable and the working conditions are changeable. The neural control system enables the manipulator to behave correctly, even if the mathematical model of the control object is unknown. In thi...

In this paper we propose a discrete tracking control system for 3 degrees of freedom (DOF) robotic manipulator control. The control system is composed of Adaptive Critic Design (ACD), a PD controller and a supervisory term derived from the Lyapunov stability theory. ACD in Dual–Heuristic Programming (DHP) configuration consists of two structures re...

In this paper a multilayer neural-net (NN) controller is applied for tracking control of robotic manipulator, which is a nonlinear object having unknown and changeable parameters. Dynamics equations of a rigid manipulator are presented. The NN controller is used for compensating manipulator nonlinearities. The controller is realized in a form of a...

In this paper a neural-net (NN) controller for tracking control of a manipulator is used. A manipulator is a nonlinear object which usually has unknown and changeable parameters. Dynamics equations of a rigid manipulator are presented. A NN controller is used for compensating manipulator's nonlinearities. The controller is realized in a form of a l...