Zdenko Bobovský

• Professor
• VSB - Technical University of Ostrava

Improving the energy efficiency in multibody robotic systems remains a key challenge in engineering. This study examines the Bennett mechanism, a four-link, specifically single degree of freedom (1-DOF), spatial mechanism with a closed-loop kinematic structure. Despite being overconstrained, its unique geometry enables smooth motion, making it suit...

This study proposes a new approach to improving laser sensor data collection through optimised sensor settings. Specifically, it examines the influence of laser sensor configurations on laser scanning measurements obtained by using a laser line triangulation sensor for transparent and non-transparent plastics, as well as aluminium alloys. Distance...

This article focuses on the integration of the Internet of Things (IoT) and the Internet of Robotic Things, representing a dynamic research area with significant potential for industrial applications. The Internet of Robotic Things (IoRT) integrates IoT technologies into robotic systems, enhancing their efficiency and autonomy. The article provides...

Featured Application The outcomes of this research can be implemented in the design of fast and easily tunable low-level controllers of redundant pneumatic parallel robots. This control algorithm allows for online stiffness changes of the robot, providing safe manipulation while maintaining the ability to use high amounts of force if needed. Abstr...

Redundant cascade manipulators actuated by pneumatic bellows actuators are passively compliant, rugged and dexterous which are qualities making them exceptionally well suited for applications in agriculture. Unfortunately bellows actuators are notoriously difficult to precisely position. This paper presents a novel control algorithm for the control...

This paper deals with the possibility of low-cost on-line compensation for thermally induced error. The aim is to compensate the drift of the UR10e collaborative robot to the extent that the robot operates with the repeatability guaranteed by the manufacturer for the thermal steady state. Thus, the authors have developed a compensation system that...

The adaptability of the robot can be increased by a shape-changing link of the robotic arm that allows to achieve a suitable kinematic structure for a given task. The principle described in this paper is the use of low melting point material (LMPM) in the design of the robotic link and focuses on the behavior of this shape-changing link during a co...

Human–robot interaction is becoming an integral part of practice. There is a greater emphasis on safety in workplaces where a robot may bump into a worker. In practice, there are solutions that control the robot based on the potential energy in a collision or a robot re-planning the straight-line trajectory. However, a sensor system must be designe...

The article deals with the design of a robot with an unconventional kinematic structure, which is able to vertically stabilize the position of the robot base for the placement of sensors and handling superstructures. The robot concept was designed to have as few actuators as possible. The robot's kinematics was solved for the purpose of simulating...

This work focuses on improving a camera system for sensing a workspace in which dynamic obstacles need to be detected. The currently available state-of-the-art solution (MoveIt!) processes data in a centralized manner from cameras that have to be registered before the system starts. Our solution enables distributed data processing and dynamic chang...

Research of customized serial manipulators seeks to robotize tasks in dense built environments, where arbitrary kinematic structures synethised for given trajectories can perform such tasks without collisions. This paper presents the effect of deformable manipulator links on manipulator working envelope and torque demand. Four manipulator structure...

In this paper, we examine a method for improving pose estimation by correctly positioning the sensors relative to the scanned object. Three objects made of different materials and using different manufacturing technologies were selected for the experiment. To collect input data for orientation estimation, a simulation environment was created where...

This paper presents a set of algorithms for the synthesis of kinematic structures of serial manipulators using multiple constraint formulation and provides a performance comparison of different kinematic representations, the Denavit-Hartenberg notation, the Product of Exponentials (screws), and Roll-Pitch-Yaw angles with translation parameters. Syn...

The paper presents a new version of the existing elastic band algorithm used for path finding, with application in the field of collaborative robotics and point-to-point movements. The algorithm places control points on the path and dynamically modifies the position of these control points in reaction to any obstacles located or moving in the works...

Human-robot collaboration is a widespread topic within the concept of Industry 4.0. Such collaboration brings new opportunities to improve ergonomics and innovative options for manufacturing automation; however, most of the modern collaborative industrial applications are limited by the fact that neither collaborative side is fully aware of the par...

This paper presents an approach to compensate for the effect of thermal expansion on the structure of an industrial robot and thus to reduce the repeatability difference of the robot in cold and warm conditions. In contrast to previous research in this area that deals with absolute accuracy, this article is focused on determining achievable repeata...

The design of a manipulator arm, which is built from a construction kit, is presented in this article. The procedure is based on the results of the discrete optimization of a truss structure and its application to a simple component system (assuming a predefined shape and material of components). A genetic algorithm is used to optimize the truss st...

In this work, we extend the previously proposed approach of improving mutual perception during human–robot collaboration by communicating the robot’s motion intentions and status to a human worker using hand-worn haptic feedback devices. The improvement is presented by introducing spatial tactile feedback, which provides the human worker with more...

The article describes a method of simulated 3D scanning of triangle meshes based on ray casting which is used to find the optimal configuration of a real 3D scanner turntable. The configuration include the number of scanners, their elevation above the rotary table and the number of required rotation steps. The evaluation is based on the percentage...

We describe a method for robotic cell optimization by changing the placement of the robot manipulator within the cell in applications with a fixed end-point trajectory. The goal is to reduce the overall robot joint wear and to prevent uneven joint wear when one or several joints are stressed more than the other joints. Joint wear is approximated by...

Robots that have been optimized in simulation often underperform in the real world in comparison to their simulated counterparts. This difference in performance is often called a reality-gap. In this paper, we use two methods, genetic algorithm and topology optimization, to optimize a quadruped robot. We look at the original and optimized robots’ p...

The need of improving the quality of professions led to the idea of simplification of processes during chimney sweeping. These processes have been essentially the same for tens of years. The goal of this paper is to bring an automation element into the chimney sweeping process, making the job easier for the chimney sweeper. In this paper, an essent...

In a collaborative scenario, the communication between humans and robots is a fundamental aspect to achieve good efficiency and ergonomics in the task execution. A lot of research has been made related to enabling a robot system to understand and predict human behaviour, allowing the robot to adapt its motion to avoid collisions with human workers....

In this paper, we investigated the effect of the incidence angle of a laser ray on the reflected laser intensity. A dataset on this dependence is presented for materials usually used in the industry, such as transparent and non-transparent plastics and aluminum alloys with different surface roughness. The measurements have been performed with a las...

Snake robots are a suitable solution for various types of applications, especially in rough terrain or hardly accessible areas such as, for example, pipes. This article deals with a snake robot moving in a pipe using a so-called trapezium-like travelling wave. In this paper, we present a mathematical model of locomotion of the snake robot in a pipe...

There are several ubiquitous kinematic structures that are used in industrial robots, with the most prominent being a six-axis angular structure. However, researchers are experimenting with task-based mechanism synthesis that could provide higher efficiency with custom optimized manipulators. Many studies have focused on finding the most efficient...

Soft gripping, in which the gripper adapts to differently shaped objects, is in great demand for use in unknown or dynamically changing environments and is one of the main research subjects in soft robotics. Several systems have already been created, one of which is a passive shape-adaptable finger based on the FinRay effect. The geometric shape of...

While repairing industrial machines or vehicles, recognition of components is a critical and time-consuming task for a human. In this paper, we propose to automatize this task. We start with a Principal Component Analysis (PCA), which fits the scanned point cloud with an ellipsoid by computing the eigenvalues and eigenvectors of a 3-by-3 covariant...

PLA is one of the most widely used materials in additive technology, especially in the Fused Filament Fabrication method. However, its use is limited by its relatively low-temperature resistance. The glass transition temperature of PLA is around 60 °C. Some studies already performed on the annealing of 3D printed plastics have shown their increased...

The paper describes the original robotic arm designed by our team kinematic design consisting of universal rotational modules (URM). The philosophy of modularity plays quite an important role when it comes to this mechanism since the individual modules will be the building blocks of the entire robotic arm. This is a serial kinematic chain with six...

Featured Application The proposed method is useful in applications where it is not possible to use a standard industrial robot because of space restrictions and it is necessary to design a custom robotic manipulator. Abstract In situations of a confined workplace with a lot of obstacles and a complicated required trajectory of the endpoint of an i...

The article aims to prove the hypothesis, that an approach direction influences repeatability at target point of a trajectory. Unlike most researches that deal with absolute accuracy, this paper is focused on determining the achievable repeatability and the influence of the direction of approach on it. To prove the hypothesis, several measurements...

Featured Application Existing camera systems may provide localization and tracking of everything marked, while AGVs do not have to carry sensors for localization and navigation themselves. This method provides centralized supervision of deployed robotic systems. Abstract The objective of this study is to extend the possibilities of robot localizat...

Featured Application Proposed method can improve efficiency of non-technological movements of robotic manipulator. This has a wide range of use in the industry, where robot provides traverse between different technological operations. Abstract Improved energy usage efficiency is a common goal for economic and environmental reasons. In this manuscr...

This paper performs a benchmark of main parameters of perception and planning available in MoveIt! motion planning framework in order to identify parameters the most affecting the overall performance of the system. The initial benchmark is performed on a virtual simulation of UR3 robot workspace with a single obstacle. The performance is measured b...

Featured Application A fast and low-cost process for automated identification of positions of workcell components, including robots. Suitable for rapid deployment of robotic applications without a need of previous simulations or CAD modeling. Abstract In this paper, a new method for the calibration of robotic cell components is presented and demon...

This paper extends the topic of monocular pose estimation of an object using Aruco tags imaged by RGB cameras. The accuracy of the Open CV Camera calibration and Aruco pose estimation pipelines is tested in detail by performing standardized tests with multiple Intel Realsense D435 Cameras. Analyzing the results led to a way to significantly improve...

In this analysis, we present results from measurements performed to determine the stability of a hand tracking system and the accuracy of the detected palm and finger’s position. Measurements were performed for the evaluation of the sensor for an application in an industrial robot-assisted assembly scenario. Human–robot interaction is a relevant to...

This paper analyzed the locomotion of a snake robot in narrow spaces such as a pipe or channel. We developed a unique experimental snake robot with one revolute and one linear joint on each module, with the ability to perform planar motion. The designed locomotion pattern was simulated in MATLAB R2015b and subsequently verified by the experimental...

The paper deals with improving the reliability of mechanical components of the mobile robot Telerescuer. This improvement is realised by monitoring thermal parameters of some selected critical points of gearboxes and drives using the principles of IoT (Internet of Things) and by transferring all measured values to the ThinksWorx servers. On-line mo...

This article presents a novel correction filter for infrared images captured by Kinect v2 sensor. Intended application areas are described and the basic concept of proposed sensory subsystem as well. Preliminary tests of the sensor Kinect v2 in real conditions gave promising results, therefore in-depth analysis of its applicability was performed. I...

The article describes the process of development of an essentially new wheel suitable both for moving on flat ground and for travelling on stairs. The stair-climbing wheel is composed of rotary circular segments arranged around a shared carrier with arms to form a complete circular profile of the wheel adapted for moving on flat ground; for travell...

The paper describes modifications of an inspection mobile robotic system. Those were carried out in order to increase the functional value of the current mobile robot. Fulfilling the required functions of the current system was evaluated in its functional tests. The acquired parameters of fulfilling the functions were compared with similar existing...

Article describes technical solution of teleoperated humanoid robotic system. To acquire position data of operator’s body Kinect sensor is used. In article are described mathematical equations used to transform data from Kinect sensor to positions of each servo motor of the robot. Article also describes software and electric structure for both comp...

The article presents a procedure of obtaining waveform of angular velocities for special segmented wheels required for smooth movement of a stair-climbing chassis on stairs. The waveform was determined for a specified velocity of the chassis using a dynamic contact analysis in the CAD system SolidWorks. The main part of the work was to verify wheth...

During the research dealing with design of a special wheel for movement on stairs it was discovered by simulations and tests on a scaled prototype that velocity of the chassis relatively to the stairs slightly oscillates when the rotation speed of the wheels is constant. The article describes a way of determination of required angular velocity of t...

The article focuses on verification of function of two proposed conceptions of special wheels that allow driving of a chassis on staircases without oscillation of the chassis centre of mass in relation to a line parallel to the flight of steps. Basic principles of the special wheels conceptions are briefly described in the beginning. Verification o...

The article describes the synthesis of the connecting system for mechatronic modules SCHUNK PowerCube PR70, PR90 and PW90. Emphasis is placed on enabling the quick reconfiguration of the kinematic structure of the manipulator for a mobile robotic system built from these modules. The article describes the process of synthesis of mechanic components...

This article describes the design of geometrical parameters for leg of six legged walking mechanism. Design uses an algorithm in Matlab program, created to use n-variables and a dynamic model of leg build in SimMechanics. Results from dynamic analysis of model are saved into nmatrixes. These matrixes are then assessed with values of criteria to get...

Inspection tasks of pipes or channels are part of the engineering practice. In the past there were investigated conventional approaches like wheeled-based mechanisms. This paper deals with unconventional approach - snake robot moving in the pipe. In the paper locomotion pattern of concertina is introduced and subsequently kinematic model of concert...

This paper describes a hardware design of connection places for an automatic detection of a newly connected module and detection of its orientation for use in the self-reconfigurable modular robotic system. It also describes a mechanical design for an energy and information transfer between modules in the system. This paper also describes testing o...

This paper describes process of an experimental evaluation of the necessary torque for disconnection of a magnetic connection mechanism. The paper describes basic information of a designed testing stand for an experimental evaluation of mechanical parameters of the automatic connection mechanism based on magnetic principle for use in self-reconfigu...

The article presents design of a new type of a module for self-reconfigurable robotic system. The designed module is a complex unit consisting of fifteen sub-modules. The module is able to connect to other modules, submodules of others modules or split itself to sub-modules to perform a desired action. This article presents the process of module sh...

The paper deals with dynamic analysis of manipulator arm which is part of 6-legged robot. The robot is designed for search and rescue purposes like searching for survivors after building collapse or earthquake. The manipulator arm has tentacle as end-effector which serves for grasping and transfer of ruins. The aim of the paper is investigation of...

The paper deals with one-chip controller Basic Atom, which is often used as control unit in mechatronics systems designed via students. Students can use our building units for training of control subsystem developing for mechatronic products. Also several theses have been done on this topic. Mechatronic systems and robots from these theses are avai...

Digital Image Correlation is a modern full-field optical method that is being used for measurement of 3D displacements and surface strains. The correlation systems using the high-speed digital cameras also allow perform dynamic measurements and vibration analysis. The paper deals with possibilities of using the high-speed correlation system Dantec...

Inverse kinematics of mechanic system is area of solution at many universities and scientific research institutions. This paper dealt with of solution problem of inverse kinematic by cyclic coordinate descent method (CCD). This method allows use n-link chain mechanism without complicated changing of control algorithm. The article is focuses on the...

The article describes a stereoscopic camera system based on a pair of separate cameras. The cameras are stationary and tilted together. The value of their tilting angle is derived in regards to their utilization of the chip area. By optimizing tilting we can maximally utilize the chip area, without the unused parts. It can increase the size of the...

Experimental methods of mechanics can be used for verification of lifespan of structures and for assessment their safe operation. For transport of radioactive materials is necessary to use packages that fulfill severe rules declared by laws and regulations. In the paper are given experimental procedures used for verification of safety of packages u...

Paper deals with possibilities of using high-speed correlation system Q-450 produced by Dantec Dynamics for determination of eigenshapes and eigenfrequencies of tested object. In the paper is described new method for experimental measurement and explained a principle of program developed specially for assessment of such measurements.

The paper deals with digital image correlation method that belongs to the most modern optical method used in experimental mechanics. The main attention is devoted to an application of this method in determination of modal parameters. There is described a methodology of measurement of eigenshapes and eigenfrequencies by high-speed correlation system...

Inverse kinematics of mechanic system is area of solution at many universities and scientific research institutions. This paper dealt with of solution problem of inverse kinematic by cyclic coordinate descent method (CCD). This method allows use n-link chain mechanism without complicated changing of control algorithm. The article is focuses on the...