Web-Based Platform for Planning and Configuration of Robot-Based Automation Solutions: A Retrospective View on the Research Project ROBOTOP

Automation solutions in production represent a sensible and long-term cost-effective alternative to manual work, especially for physically strenuous or dangerous activities. However, especially for small companies, automation solutions are associated with a considerable initial complexity and a high effort in planning and implementation. The ROBOTOP project, a consortium of industrial companies and research institutes has therefore developed a flexible web platform for the simplified, modular planning and configuration of robot-based automation solutions for frequent tasks. In this paper, an overview of the project’s scientific findings and the resulting platform is given. Therefore, challenges due to the scope of knowledge-based engineering configurators like the acquisition of necessary data, its description, and the graphical representation are outlined. Insights are given into the platform’s functions and its technical separation into different Microservices such as Best Practice selection, configuration, simulation, AML-data-exchange and spec-sheet generator with the focus on the configuration. Finally, the user experience and potentials are highlighted.

Hardware Phase Shift Hybrid Precoding Designs For Multi-User Massive MIMO Systems

Hybrid precoding is a challenging design for massive MIMO systems that involves a combination of analog and digital processing, aiming to maximize the spectral efficiency (SE). Most works on hybrid precoding focus on the single phase shifter (SPS) implementation to adapt the phase from RF chains to antennas. In this paper we propose to develop the double phase shifter (DPS) and the fixed phase shifter (FPS) in both single-path and multi-path configuration. Simulation results certify a significant improvement for both proposed implementations with high hardware efficiency (HE) and high spectral efficiency especially in multi-path environment.

Performance Enhancement of Reconfigurable Metamaterial Reflector Antenna by Decreasing the Absorption of the Reflected Beam

In this study, a new concept for a Ka-band 5G communication tunable reflector metasurface (MS) for beam steering at 28 GHz is proposed. Varactor diodes are used as the tunability component of each unit cell of this MS. Significant improvements in beam steering and bandwidth performance were achieved using this new concept referred to as the stripes configuration. Several different geometries of unit cells arranged in stripes were designed to achieve better performance in directionality, gain, sidelobe level (SLL), and bandwidth in the stripes configuration. Simulation results for a three-stripe MS with different unit cells in each stripe showed better performance in the phase dynamic range and reduced reflectance losses compared to a typical one-stripe MS. The simulation results showed a significant improvement of 3 dB, depending on the steering angle in reflectance gain, compared to a uniform MS (one stripe). Furthermore, a significant improvement of approximately 50% in the accuracy of the steering angle for different operating frequencies was demonstrated. Manufacturing considerations are discussed in this study.

Configuration of the Martian dust rings: shapes, densities, and size distributions from direct integrations of particle trajectories

ABSTRACT It is expected since the early 1970s that tenuous dust rings are formed by grains ejected from the Martian moons Phobos and Deimos by impacts of hypervelocity interplanetary projectiles. In this paper, we perform direct numerical integrations of a large number of dust particles originating from Phobos and Deimos. In the numerical simulations, the most relevant forces acting on the dust are included: Martian gravity with spherical harmonics up to fifth degree and fifth order, gravitational perturbations from the Sun, Phobos, and Deimos, solar radiation pressure, as well as the Poynting–Robertson drag. In order to obtain the ring configuration, simulation results of various grain sizes ranging from submicrometres to 100 μm are averaged over a specified initial mass distribution of ejecta. We find that for the Phobos ring grains smaller than about 2 μm are dominant; while the Deimos ring is dominated by dust in the size range of about 5–20 μm. The asymmetries, number densities, and geometric optical depths of the rings are quantified from simulations. The results are compared with the upper limits of the optical depth inferred from Hubble observations. We compare to previous work and discuss the uncertainties of the models.

Physical modeling and geometry configuration simulation for flexible cable in a virtual assembly system

Purpose In this paper, a novel and unified method for geometry configuration simulation of flexible cable under certain boundary conditions is presented. This methodology can be used to realize cable assembly verification in any computer-aided design/manufacturing system. The modeling method, solution algorithm, geometry configuration simulation and experimental results are presented to prove the feasibility of this proposed methodology. The paper aims to discuss these issues. Design/methodology/approach Considering the gravity, bending and torsion, modeling of cable follows the Kirchhoff theory. For this purpose, Euler quaternions are used to describe its spatial geometry configuration by a carefully chosen set of coordinates. Then the cable is discretized by the FEM, and the equilibrium condition per element is computed. In this way, the global static behavior is independent of the discretization. The static evolution of the cable is obtained by numerical integration of the resulting Kirchhoff equations. Then the manner is demonstrated, in which this system of equations can be decoupled and efficiently solved. Geometry configuration simulation examples with different boundary conditions are presented. Finally, experiment validation are given to describe the effectiveness of the models and algorithms. Findings The method presented in this paper can be adapted to computer-aided assembly verification of flexible cable. The experimental results indicate that both of the model and algorithm are efficient and accurate. Research limitations/implications The method should be extended to flexible cables with multiple branches and more complex constraints (holes, curved surfaces and clamps) and non-circular sections. Dynamic assembly process simulation based on the Kirchhoff theory must be considered in the future. Originality/value Unlike in previous approaches, the cable behavior was independent of the underlying discretization, and the finite element approach enables physically plausible cable assembly verification.

Local Coupled Extreme Learning Machine Based on Particle Swarm Optimization

We developed a new method of intelligent optimum strategy for a local coupled extreme learning machine (LC-ELM). In this method, both the weights and biases between the input layer and the hidden layer, as well as the addresses and radiuses in the local coupled parameters, are determined and optimized based on the particle swarm optimization (PSO) algorithm. Compared with extreme learning machine (ELM), LC-ELM and extreme learning machine based on particle optimization (PSO-ELM) that have the same network size or compact network configuration, simulation results in terms of regression and classification benchmark problems show that the proposed algorithm, which is called LC-PSO-ELM, has improved generalization performance and robustness.

Backscattered Electrons Spectra and Angular Distributions: Simulations with EGS5

The purpose of the present study is to compare numerical Monte Carlo simulations of backscattering of electrons, mainly in the keV range, with available experimental data. The final goal is to assess the ability of the Monte Carlo code to predict viable results, in view of the complexity and difficulty of performing experimental measurements. A specific code for simulating electrons backscattering was developed, based on the EGS5 electron-photon transport routines. The code was parallelized very efficiently for a common memory configuration. Simulation results for the backscattering coefficient h, the energy spectrum dh/dq, and the angle dependent energy spectrum dh/dqdW were obtained. Comparing with experiments shows agreement from very good to fair, especially in regions of high q (energy) values. For low values of q there are not experimental results due to difficulties in measurements. Hence, the Monte Carlo program can provide good estimates, in the range of energies from tens of keV up to 100-200 keV.

A New Railway Bridge on Gornalunga River: a Flood Modeling Study.

In the present work, a 1D-2D-coupled model was used to perform hydraulic analysis of Gornalunga River (Sicily), in order to estimate and analyze the flood risk in correspondence of a crossing bridge. In the frame of the project “Speed up of the railway line Catania-Syracuse”, an existing bridge, crossing Gornalunga River, has to be enlarged and a configuration that mitigates the hydraulic risk on the surrounding area has to be found. At this aim, two different future configurations were considered and a flood modeling study in proximity of the railway crossing in existing and future configurations was conducted using MIKE FLOOD. Depths of flowing water through the bridge, as well as the maximum flood extent and maximum inundation depth have been evaluated for each scenario in order to identify the configuration that minimizes the hydraulic risk for the surrounding area. Finally, the effectiveness of this last solution is analyzed and discussed by comparison with the actual configuration. Simulation results demonstrate that in proximity of the railway bridge water level, as well the hazard risk of the surrounding area decrease passing from the actual configuration to the future one.

A SIMULATION-AS-A-SERVICE FRAMEWORK FACILITATING WEBGIS BASED INSTALLATION PLANNING

Installation Planning is constrained by both natural and social conditions, especially for spatially sparse but functionally connected facilities. Simulation is important for proper deploy in space and configuration in function of facilities to make them a cohesive and supportive system to meet users’ operation needs. Based on requirement analysis, we propose a framework to combine GIS and Agent simulation to overcome the shortness in temporal analysis and task simulation of traditional GIS. In this framework, Agent based simulation runs as a service on the server, exposes basic simulation functions, such as scenario configuration, simulation control, and simulation data retrieval to installation planners. At the same time, the simulation service is able to utilize various kinds of geoprocessing services in Agents’ process logic to make sophisticated spatial inferences and analysis. This simulation-as-a-service framework has many potential benefits, such as easy-to-use, on-demand, shared understanding, and boosted performances. At the end, we present a preliminary implement of this concept using ArcGIS javascript api 4.0 and ArcGIS for server, showing how trip planning and driving can be carried out by agents.