This paper describes the development of Pathfinder - an autonomous guided vehicle (AGV) intended for the transportation of material in hospital environments. Pathfinder is equipped with the latest industrial hardware components and employs the most recent software stacks for autonomous localization, navigation and mapping. As the most significant contribution to the current robotics development, Powerlink interface enabling direct data transfers between Robot Operating System (ROS) and Powerlink compatible hardware was developed. This combination is in our best knowledge reported here for the first time and the results with comprehensive tutorial were made publicly available as a Github repository. The capabilities of Pathfinder were explored during preliminary on-site tests in local hospital. From experimental results in a hospital it was confirmed that the robot can move along its global path, and reach the goal without colliding with static and moving objects.

This paper describes the development of Phollower—an autonomous mobile robot intended to perform various logistical tasks in both industrial and civil environments. Phollower is equipped with the latest types of industrial components and sensors. It also employs advanced embedded navigation and localization software to create its own virtual maps and thereby to navigate autonomously within the mapped area. The whole development process has been focused on building a device that meets European safety standards. Phollower is a universal mobile platform that can be quickly expanded with specialized add-ons. A germicidal add-on for disinfection of indoor areas using UV-C light is described as a technology that helps to battle with the ongoing COVID-19 pandemic crisis. The hardware topology combined with the proposed open Programmable Logic Controller (PLC) code and open-Powerlink communication bus creates a unique and easily extendable robot platform.

The sensorless control of the permanent magnet synchronous motor (PMSM) has attracted wide attention due to its high reliability, economic and safety benefits. A fast and high-precision rotor-position estimation is inevitable for the implementation of sensorless control. Sliding-mode observer (SMO) is a preferred solution for sensorless control by many industrial companies. This article addresses the comparison of different switching functions employed in the control structure of sensorless field-oriented control with SMO. The switching functions are classified and their influence on the performance of the PMSM is verified for different shaping coefficients (SC). In addition, a statistical evaluation of the switching functions is provided to find the optimal values of SC. An experimental and statistical evaluation validated the substitutability of signum and hyperbolic switching functions and optimal values of SC have been found.

This paper presents the design of Unscented Kalman Filter (UKF) for estimation of state space variables of permanent magnet synchronous machine (PMSM). The UKF is shown together with the field oriented speed control. At first, the position and the speed of PMSM are measured, and UKF is used only for a load torque estimation. It is indicated how differences in sampling time of the speed and the current loop affects overall estimation performance. Subsequently, speed sensorless performance of the UKF with the same parameters is shown for comparison. Designed filter is verified only by Matlab simulation.

Dynamic Emulation of Mechanical Loads - An Approach Based on Industrial Drives' Features

The paper describes the design procedure for a finite control set model predictive control (FCS-MPC) of brushed permanent magnet DC (PMDC) machine supplied from DC-DC converter. Full order linear Kalman filter is used for estimation of an unmeasured load torque and reduction of speed measurement noise. A new cost function has been introduced with a feedforward dynamic current component and a feedforward static load current component. The performance of the proposed control strategy is compared to the conventional PI-PWM cascade speed control through the experimental verification on the 250 W laboratory prototype. Obtained results show excellent dynamic behaviour and indicate possible energy savings of the proposed speed control.