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This paper deals with the design and implementation of a universal cyber-physical model capable of simulating any production process in order to optimize its logistics systems. The basic idea is the direct possibility of testing and debugging advanced logistics algorithms using a digital twin outside the production line. Since the digital twin requires a physical connection to a real line for its operation, this connection is substituted by a modular cyber-physical system (CPS), which replicates the same physical inputs and outputs as a real production line. Especially in fully functional production facilities, there is a trend towards optimizing logistics systems in order to increase efficiency and reduce idle time. Virtualization techniques in the form of a digital twin are standardly used for this purpose. The possibility of an initial test of the physical implementation of proposed optimization changes before they are fully implemented into operation is a pragmatic question that still resonates on the production side. Such concerns are justified because the proposed changes in the optimization of production logistics based on simulations from a digital twin tend to be initially costly and affect the existing functional production infrastructure. Therefore, we created a universal CPS based on requirements from our cooperating manufacturing companies. The model fully physically reproduces the real conditions of simulated production and verifies in advance the quality of proposed optimization changes virtually by the digital twin. Optimization costs are also significantly reduced, as it is not necessary to verify the optimization impact directly in production, but only in the physical model. To demonstrate the versatility of deployment, we chose a configuration simulating a robotic assembly workplace and its logistics.

This paper presents a structural health monitoring and parameter estimation system for vibrating active cantilever beams using low-cost embedded computing hardware. The actuator input and the measured position are used in an augmented nonlinear model to observe the dynamic states and parameters of the beam by the continuous-discrete extended Kalman filter (EKF). The presence of undesirable structural change is detected by variations of the first resonance estimate computed from the observed equivalent mass, stiffness, damping, and voltage-force conversion coefficients. A fault signal is generated upon its departure from a predetermined nominal tolerance band. The algorithm is implemented using automatically generated and deployed machine code on an electronics prototyping platform, featuring an economically feasible 8-bit microcontroller unit (MCU). The validation experiments demonstrate the viability of the proposed system to detect sudden or gradual mechanical changes in real-time, while the functionality on low-cost miniaturized hardware suggests a strong potential for mass-production and structural integration. The modest computing power of the microcontroller and automated code generation designates the proposed system only for very flexible structures, with a first dominant resonant frequency under 4 Hz; however, a code-optimized version certainly allows much stiffer structures or more complicated models on the same hardware.

This article presents the collision-free manipulation of a robotic arm mounted to a mobile robotic unit, using the MS Windows Kinect 3D optical camera system. The 3D optical system is used to recognize objects, aiding the collision-free manipulation of the said objects with the arm of a mobile robotic system (MRS). The placement of the optical system directly on the robotic arm is essential to ensure the autonomy of the overall system. The MRS is able to recognize pre-defined objects in three dimensional space and approach and manipulate these automatically using its robotic arm. The aim of this article is to present the algorithms used in the mobile robot to guarantee the collision-free manipulation of the MRS with objects. The novelty of our approach lies in the a priori collision avoidance strategy, instead of solving collision states as they occur. In addition to this, the article presents the localization of objects in space. For this, randomly placed balls are localized by the MRS, estimating their real coordinates. Instead of using the standard RGB colorspace, we propose to utilize the HSV colorspace to assess object coordinates, since it provides more consistent results in case the ambient lightning intensity varies.

The paper deals with the design and construction of a universal robotic vehicle prototype, used for laboratory and educational purposes. The main goal is its use as a technology demonstrator for the needs of students, therefore it is equipped with several kinds of sensors and universal advanced control technologies and design solutions. Its basis is a control system and construction concept using mobile battery gear and omnidirectional Mecanum wheels. A manipulating arm and advanced tracking and spatial navigation systems are also components of the design. Since the problem of a customized design and construction of such a robotic vehicle is very complex and solved in various scientific fields, in this paper we will mainly focus on the detailed description of the control systems and subsystems of the vehicle. AbstraktPríspevok sa zaoberá návrhom a stavbou prototypu univerzálneho robotického vozidla, slúžiacieho pre laboratórne a študijné účely. Účelom je jeho využitie ako technologického demonštrátora pre potreby študentov, z tohto dôvodu je osadený univerzálne všetkými dostupnými druhmi snímačov a univerzálnymi pokrokovými riadiacimi technológiami a konštrukčnými riešeniami. Základom je jeho riadiaci system a konštrukčné prevedenie s batérióvym pohonom pre všesmerové Mecanum kolesá. Súčasťou konštrukcie je aj manipulačné rameno a pokrokové systémy lokalizácie a navigácie v priestore. Nakoľko problematika vlastného návrhu a stavby takéhoto mechatronického robotického vozidla je veľmi obsiahla a riešená v rôznym vedných oblastiach, budeme sa v tomto príspevku konkrétne venovať jeho riadiacim systémom a podsystémom, ktoré si podrobnejšie rozpíšeme.