Indoor Localization Simulation Framework for Optimized Sensor Placement to Increase the Position Estimation Accuracy

Indoor position estimation is an important part of any indoor application which contains object tracking or environment mapping. Many indoor localization techniques (Angle of Arrival – AoA, Time of Flight – ToF, Return Time of Flight – RToF, Received Signal Strength Indicator – RSSI) and technologies (WiFi, Ultra Wideband – UWB, Bluetooth, Radio Frequency Identification Device – RFID) exist which can be applied to the indoor localization problem. Based on the measured distances (with a chosen technique), the position of the object can be estimated using several mathematical methods. The precision of the estimated position crucially depends on the placement of the anchors, which makes the position estimate less reliable. In this paper a simulation framework is presented, which uses genetic algorithm and the multilateral method to determine an optimal anchor placement for a given pathway in an indoor environment. In order to make the simulation more realistic, the error characteristics of the DWM1001 UWB ranging module were measured and implemented in the simulation framework. Using the proposed framework, various measurements with an optimal and with a reference anchor placement were carried out. The results show that using an optimal anchor placement, a higher position estimation accuracy can be achieved

Indoor localization simulation framework for optimized sensor placement to increase the position estimation accuracy

Indoor position estimation is an important part of any indoor application which contains object tracking or environment mapping. Many indoor localization techniques (Angle of Arrival – AoA, Time of Flight – ToF, Return Time of Flight – RToF, Received Signal Strength Indicator – RSSI) and tech- nologies (WiFi, Ultra Wideband– UWB, Bluetooth, Radio Frequency Identification Device – RFID) exist which can be applied to the indoor localization problem. Based on the measured distances (with a chosen technique), the position of the object can be estimated using several mathematical methods. The precision of the estimated position crucially depends on the placement of the anchors, which makes the position estimate less reliable. In this paper a simulation framework is presented, which uses genetic algorithm and the multilateral method to determine an optimal anchor placement for a given pathway in an indoor environment. In order to make the simulation more realistic, the error characteristics of the DWM1001 UWB ranging module were measured and implemented in the simulation framework. Using the proposed framework, various measurements with an optimal and with a reference anchor placement were carried out. The results show that using an optimal anchor placement, a higher position estimation accuracy can be achieved

Numerikus modellezés és szimuláció az anyagtudományban és az anyagtechnológiákban = Numerical Modelling and Simulation in material Sciences and Materials Processing Technologies

Végeselemes modellezéssel elemeztük a technológiai folyamatok során lejátszódó anyagszerkezeti, mechanikai és termikus folyamatok együttes hatását. Matematikai modellt dolgoztunk ki egyedi és átlapolódó nyomvonalak alkalmazásával a hőeloszlás végeselemes modellezésére lézeres felületedzés és felületátolvasztás esetére, a hőhatás okozta anyagszerkezeti változások, a keménység- és feszültség-eloszlás meghatározására. Folyamatos hűtésű C-görbék alkalmazásán alapuló számítógépes hőkezelés technológiai tervezőrendszert dolgoztunk ki, acélok edzési, megeresztési, normalizálási és lágyítási technológiáinak elemzésére, műveleti utasítások készítésére, termokémiai eljárások és a betétedzés technológiájának tervezésére. Numerikus modellezési eljárást fejlesztettünk ki sajtolóhegesztési eljárások optimalizálására. Vékonylemezek ponthegesztett kötéseinek optimalizálása témakörben PhD doktori értekezés készült. Számítógépes tanácsadó rendszert dolgoztunk ki különféle hegesztési eljárások technológiai paramétereinek meghatározására, a hegesztés előírt dokumentumainak számítógépes elkészítésére. Lemezalakító eljárások numerikus modellezésével elemeztük a technológiai és szerszámparaméterek hatását. A húzóbordás mélyhúzás numerikus modellezése témakörben PhD doktori értekezés készült. Sorozatszerszámban végezhető lemezalakító eljárások technológiai és szerszámtervezésére alkalmas rendszert dolgoztunk ki általános rendeltetésű CAD rendszerre építve. | The complex structural, mechanical and thermal effects in various technological processes were analysed using FEM. Mathematical model has been elaborated for single and overlapped tracks to determine the temperature distribution, phase transformations, hardness and stress distribution during laser surface hardening and surface melting. Based on the CCT-diagrams, a computer aided technological design program was elaborated for heat-treatment processes, suitable to analyse hardening, case hardening, tempering, normalising and annealing of structural and tool steels, and to design various thermo-chemical heat-treatment processes. Numerical modelling procedure has been elaborated for optimising pressure welding processes. For optimisation of spot-welding processes of thin sheets PhD Thesis was defended. Computer Aided Expert System was elaborated to design various welding processes determining the decisive technological parameters, and preparing the necessary welding specifications (WPS). Applying numerical modelling, the effect of technological and die parameters on various sheet metal forming processes were analysed with particular emphasis on forming of car body panels with deep-drawing. A PhD Thesis was defended on the investigation of deep-drawing processes applying drawbeads. Based on the Unigraphics CAD system, a computer aided technological and die-design system for sheet metal forming processes performed in progressive dies has been elaborated

Implementation of neurobiological and various signal processing algorithms using FPGA circuits

Signal processing is an important part of computer science, which is used in but not limited to automation, pattern recognition, control theory, artificial intelligence, and networking and communication. A signal can be anything, which is measurable and everything that can be measured is also can and inevitably will be processed using analog or digital signal processing methods. It can be a temperature measurement, an image from a camera or a recording of neural brain activity, all of them have to be processed in some way. In signal processing the first step is to measure a physical quantity. After the measurement the quantity can be filtered and amplified. In ideal circumstances a noise-free and proper amplitude quantity can be converted to a digital signal using an analog-digital converter (ADC). This digital signal can be processed by a Central Processing Unit (CPU) / microprocessor, a microcontroller, a Graphics Processing Unit (GPU), a Field Programmable Gate Array (FPGA) or an Application-Specific Integrated Circuit (ASIC). Changing the hardware in signal processing applications are a complex task and usually requires to modify an optimised software. In many cases only software optimisation offers limited improvements, although the time and energy investment is still significant. In these cases the usage of FPGA makes possible to rapidly change the hardware architecture along with the software and also offers real-time and efficient operation. The PhD thesis presents FPGA-based real-time signal processing, including the detection and classification of action potential in neurophysiological measurements. A common feature of the presented approaches is real-time implementation using FPGA. The dissertation consists of three major parts. The first chapter presents real-time detection and synthesis of neurophysiological signals based on FPGA, the second chapter presents real-time classification of neurophysiological signals based on spatial information, while the third chapter presents the application of FPGA-based systems in signal processing and simulation

Implementation of an FPGA-based actual observer for active suspension control

In the case of vehicle automation the central role is played by the security, the reliability and the convenience. The elements used in a suspension system with fixed parameter values do not provide the desired safety and comfort conditions in all circumstances. In this paper an active suspension system is presented, which is capable of minimal sensor information based efficient intervention. The proposed architecture enables a costeffective and energy efficient implementation of an actual observer. In this work the mathematical model, the analysis of the model, the measured variables, the design of the actual observer and the Field Programmable Gate Array (FPGA) implementation if the actual observer is presented. The accuracy and the correct operation of the proposed FPGA-based actual observer controlled active suspension system are validated by simulations