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The high number of occupational accidents occurring every year in the industrial sector is still one of the main social policy action areas of governments worldwide. Both technical and human failures are often addressed as the main causes for accidents at work. However, the lack of full hazard prevention effectiveness from currently available Safeguarding Devices is another factor that should be considered, at least, from an engineering viewpoint. This paper presents a recently patented Access Detection and Machine Cycle Tracking System (ADMCTS) for industrial machinery with active safety purposes. Active safety paradigm has greatly succeeded in the automotive sector in the last years, dramatically improving road traffic accident prevention by means of active devices with real-time capabilities. Based on a dedicated Computer Vision System (CVS) for real-time video analysis of a monitored safety zone, the ADMCTS performs three main functions: access and presence detection of objects entering and/or remaining within the monitored zone, machine cycle tracking, and warning and alarm signal handling to ensure that machine functions are only allowed when workplace conditions are safe. Machine cycle tracking provides the ADMCTS with an adaptive risk assessment capability for optimal prevention. In order to provide a thoughtful description of its functionality, a state machine model of the ADMCTS is introduced, and a visual walk-through of this model, as applied on a generic cutting machine, is also discussed.

We report on the synthesis of Bi0.4Sr0.6FeO3 powder with cubic structure by solid state reaction (mechanical milling and calcination) from Bi2O3, SrCO3 and Fe2O3 stoichiometric ratios. Milled powder mixtures were heat treated between 775∘C and 825∘C for 30 and 60 min in oxygen atmosphere and characterized by X-ray diffraction (XRD), impedance as well as Mossbauer spectroscopy. The cubic phase of Bi0.4Sr0.6FeO3 was successfully obtained in samples milled for only 2 h and a subsequent calcination at 800∘C. Irrespective of milling time, heat treatments at lower temperatures (775∘C) still show spurious phases such as Sr0.23Bi0.76O1.1 (30 min) and Sr0.53Bi1.72O3 (60 min). Impedance spectroscopy show high values (105–109) Ω indicating strong structural bond between the atoms of the system and activation energies for the strontium ion around 04 eV. These results show a single dynamic behavior in a range from 1 to 2*105 Hz enabling data adjustment and analysis to a RC circuit. Conductivity results normally show a behavior that obeys the universal law of Jonscher’s relaxation (σ = σDc + αωn) with values for the exponent n (0.8 < n < 1) typical in these structures. Mossbauer spectrometry measurements reveal that the hyperfine magnetic field of the precursors and milled powders corresponds to hematite 512 T. After the thermal treatment of the samples, the mean hyperfine field decreases to 489 ± 0.5 T showing the Bi and Sr atoms diffusion, (non- magnetic) in Fe2O3. While the result of isomer shift corresponds to a Fe+3 oxidation state irrespective of the heat treatment.