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Zsolt Kovács, Zsolt Janos Viharos, János Kodacsy, Roland Sándor
Magnetic Assisted Ball Burnishing of Magnetizable and Non-Magnetizable Materials

The goal of the reported research was to evaluate the machining conditions the magnetizable and non-magnetizable materials by the novel permanent Magnetic Assisted Ball Burnishing (MABB) tool. C45 steel, KO36 austenite steel, AA7075 aluminium and PA6 polymer materials were applied in the experiments. The main aim was to determine the optimal the technological parameters for these materials taking in consideration the hardness and roughness of the surface, too. Taguchi design of experiment methodology was applied in this study to simply look for optimal technology, compared to other kinds of technologies reported in various scientific papers. Surface quality is a complex feature that refers to the micro-geometrical characteristics of the machined surface. It includes roughness and waviness and gives a realistic picture about the top of the surface, while micro hardness and grains structure are especially important on sub-surface level. The results mirrored that all of the tested materials can be burnished by the MABB tool, however, the results from the economical viewpoints are diverse. The MABB tool was mainly designed to reduce the surface roughness but this cold metal forming process has further result like the surface hardening and further conclusions were also drawn that the MABB tool:

  • capable to reduce the surface of non- magnetizable materials, too,
  • increases the surface hardness of C45
. magnetic assisted ball burnishing, technology optimization, material hardness, surface roughness.
Domenico Capriglione, Marco Carratù, Marcantonio Catelani, Lorenzo Ciani, Gabriele Patrizi, Roberto Singuaroli, Paolo Sommella
Experimental analysis of IMU under vibration

MEMS-based Inertial Measurement Units are today widely employed in many contexts. Especially in the field of self-driving vehicles and navigation they provide important information to the electronic control units for implementing positioning, localization and tracking algorithms. As a consequence, it becomes important to analyse the accuracy, reliability and time to failure of such systems when operating in conditions as more as possible similar to ones experienceable in the practice. To these aims, in this paper we investigate on IMU performance under random vibration which can be thought of as a kind of stress to which IMUs are continuously interested during their common operating. The experimental results have proved that these devices are very sensitive to the considered conditions and that suitable measurement procedures and measurement setup should be designed for the IMUs performance analysis.

Balázs Scherer
RTOS aware non-intrusive testing of cyber-physical systems in HIL (Hardware In the Loop) environment

Statistics show that more and more cyber-physical systems are using RTOS (Real-Time Operating System). RTOS based system software can introduce multitasking and real-time behaviour based errors. Therefore, the testing processes of such systems should address the detection of these possible errors. Unfortunately, the multitasking and real-time behaviour based errors are among the hardest to detect. The best way for the detection is to perform extensive testing in a very realistic environment like in a HIL (Hardware In the Loop) simulation. These environments provide the possibility to perform overloaded event simulation, that increase the chance of multitasking and real-time behaviour based error occurrence. Traditionally the RTOS aware measurement methods (providing information for the error detections) use software instrumentation, and are not integrated into HIL test environments. This paper introduces a novel integration of RTOS aware measurements into a HIL test development environment. Our integration also focuses on the non- intrusive measurements of multitasking behaviour of RTOS based software systems. These non-intrusive measurements are not widespread and their integration into a HIL based environment is also a novel solution.

Bikram Chaudhuri, Sayfe Kiaei
Delta-Sigma Data Converters for Wireless Applications

This paper gives an over view of the Delta-Sigma (∆Σ) converters for wireless applications. First an overview of data converters is presented, followed by Fractional-N frequency synthesizers. The aim is to give an overview of the subject, and present sufficient level of detail while covering all essential aspects.

David J. Allstot, Jianjun Guo, Ward J. Helms, Waisiu Law, Charles T. Peach
True N-Bit Calibration of Pipeline A/D Converters: Trends and Challenges

The digital calibration algorithm for conventional 1-b/stage pipelined analog-to-digital converters introduced by Karanicolas et al. [1] occasionally leads to missing or non- monotonic digital codes. In this paper, we show that an extension of that algorithm to 1.5-b/stage architectures actually leads to more frequent code errors. We also describe two methods to improve A/D performance in the presence of non-linear operational amplifiers. The first method uses a calibration that assures monotonicity in the presence of arbitrary comparator offset voltages. The second method employs an input-dependent level-shifting stage to achieve high linearity.

Sebastien Fievet, Sirag Gokoglu, Emmanuel Marais, Roberto Rivoir
DESIGN, SIMULATION, AND TEST STRATEGIES FOR ANALOG-TO-DIGITAL, DIGITAL-TO-ANALOG CONVERSION CHANNELS IN WIRELESS APPLICATIONS

In this paper, considering as driving example an analog base-band processor for mobile communications, integrating complete A/D and D/A data conversion based IPs, as transmit/receive base-band ports, voice-audio codecs, auxiliary codecs, we will present an overview of a number of design-for-test, modeling, simulation, and test strategies, aiming to ensure both a complete and economical test of the chip. Our goal will be not only to highlight the effectiveness of a synergic deployment of techniques, like analog design-for-testability (DFT), design modeling, statistical analysis, correlation of electrical parameters, on-chip test overhead (ABIST = Analog BIST), on-board circuit overhead, definition of different test levels and specific test sequence, but also the imperative need to collect and exploit, within the project context, the complete fan of microelectronics “techno-cultures” [1], like design, characterization, test, and product engineering, without which a readily “time-to-market”, fully-tested product introduction would be not feasible.

Yann Deval, Dominique Dallet, Jean-Baptiste Bégueret
Toward Software Defined Radio : The ADC Goes from Baseband to Antenna

A general overview of radio receivers and transmitters is presented. Introducing the principle of frequency translation, classical heterodyne and homodyne RX and TX architectures for analog telecommunications are discussed. Digital telecommunications are addressed and, with them, modern polyphased transceiver architectures and the insertion of an ADC within the receiver chain. First the ADC is considered at the baseband level, then at higher frequency stages, and up to the antenna yielding to the ultimate Software Defined Radio (SDR) principle. At each location of the ADC within the receiver chain, the converter characteristics are reviewed, leading to the choice of a possible architecture. Nonidealities are discussed in order to highlight problems that researchers will have to address in the future to fulfill the SDR concept.

Yang Cai, Yongxiang Hu, Mel Siegel, Sriram Janakiram Gollapalli, Ashish R. Venugopal, Ulas Bardak
Onboard Feature Indexing from Satellite Lidar Images

The purpose of the onboard feature indexing system is to perform pattern recognition and data compression onboard. We use the unsupervised machine learning algorithm k-means to classify the lidar profile data and generate an index dictionary. Then we train the Radial Basis Function neural network with the index dictionary on ground computers. Finally, we use the same RBF model for the onboard feature recognition and indexing. We implemented a prototype of the onboard computer with ZISC (Zero Instruction Set Computing) chips and FPGA (Field Programmable Gate Array) so that it takes advantage of intrinsic parallel computing and reconfigurability. We tested a set of 44K profiles as the training set to learn prototypical profiles that make up the indexing dictionary. With 64 indices, we reach a high compression rate 99.17% with reasonable error range. We found the required neurons are equal to the indices. We also compared our method to wavelet algorithm and found that it significantly outperforms the wavelet compression technique.

S. Caorsi, M. Donelli, G. L. Gragnani, A. Massa, M. Pastorino, A. Randazzo
Digital-image formation based on the inversion of microwave scattering data

Among the various imaging systems, the ones based on electromagnetic waves in near-field conditions are considered in this paper. In particular, two reconstruction approaches based on stochastic concepts are discussed. Starting from tomographic configurations, the integral equations of the inverse scattering problem are discretized and solved by using a genetic algorithm and a simulated annealing. The effects of the presence of the so-called nonradiating current are also taken into account.

G. Tognola, C. Svelto, M. Parazzini, P. Ravazzani, F. Grandori
Contact-less 3D-Coordinate Measurement System by Laser Scanning and Image Reconstruction from Unorganized Data

A simple but robust and efficient 3D laser scanner was developed for data point acquisition from an object surface. The system is mainly developed for digital registration of anatomical parts to be used in biomedical applications. A novel surface reconstruction algorithm is adopted to obtain an explicit 3D model for the measured object with adequate ease and accuracy. Some of the practical applications of this contact-less scanning system, as well as its first step metrological validation are presented.

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