On-Line Monitoring of The Axial Thermal Displacement of Machine Tools By Using A Laser Mouse Sensor

This paper presents a low-cost on-line system for monitoring the axial thermal displacement of machine tools. The proposed monitoring system includes an embedded optical sensor derived from a laser mouse; an image acquisition microcontroller; speckle patterns; and an edge computer that hosts software including an image display module, a displacement calculation module, an image enhancement module, and a data visualization module. The proposed sensing system can measure the displacement in two orthogonal directions simultaneously by employing digital image correlation; thus, the proposed system is a two-dimensional displacement sensor. The sensing system benefits from image enhancement techniques and customized optimal speckle patterns printed using a standard low-cost monochrome laser printer. Experimental results indicate that the proposed displacement sensing system has an accuracy and a precision of less than 5 mm in both orthogonal directions; however, the measurement range is only 1 mm for a static measurement. The two-dimensional displacement sensing system was used for the on-line monitoring of the thermal deformation of a feed drive system for machine tools, and the performance of the sensing system was assessed experimentally.

On-Line Monitoring of the Axial Thermal Displacement of Machine Tools by Using a Laser Mouse Sensor

This paper presents a low-cost on-line system for monitoring the axial thermal displacement of machine tools. The proposed monitoring system includes an embedded optical sensor derived from a laser mouse; an image acquisition microcontroller; speckle patterns; and an edge computer that hosts software including an image display module, a displacement calculation module, an image enhancement module, and a data visualization module. The proposed sensing system can measure the displacement in two orthogonal directions simultaneously by employing digital image correlation; thus, the proposed system is a two-dimensional displacement sensor. The sensing system benefits from image enhancement techniques and customized optimal speckle patterns printed using a standard low-cost monochrome laser printer. Experimental results indicate that the proposed displacement sensing system has an accuracy and a precision of less than 5 mm in both orthogonal directions; however, the measurement range is only 1 mm for a static measurement. The two-dimensional displacement sensing system was used for the on-line monitoring of the thermal deformation of a feed drive system for machine tools, and the performance of the sensing system was assessed experimentally.

Using Quantitative Characteristics of Document Images for Identification of Laser Printers

The article provides a brief overview of the current state of the theory and practice of identifying laser printers and the results of research work aimed at discovering individual features of the printing mechanism of a laser printer.The author analyses the scheme of a laser printer, describes the printing cycle, presents the main results of the analysis of a printer’s mechanism and the influence of its individual parts on the optical density of printing. The method of assessment of the optical density of the print by the digital image of the printed document is proposed, the complex of the necessary technical and program tools is described.A hypothesis on the correlation between fluctuations in the optical density of printing of solid fills and fluctuations in the area of printed elements was put forward and confirmed; a visual representation of the study results in graphical form is presented, the relationship between the shape of the obtained graphs and defects of the printer’s components and parts is substantiated. The author proposes ways to detect the inhomogeneity of printing density on text arrays based on changes in the area of printed elements and processing of the results, which allows comparing distributions for texts printed in fonts of different sizes and styles. Based on experimental material, the individuality of the form of the obtained distributions and the possibility of their use as identifying features of the printing device are substantiated.

NUMBER OF FINE PARTICLES’ AND THEIR MASS CONCENTRATION: COMPARISON OF EMISSION OF NEW PRINTING TECHNOLOGY VERSUS TRADITIONAL LASER TECHNOLOGY

For many years the printers have been essential part of our offices and exposures from various printing technologies have been widely researched. The main objective of this study was to compare emitted number and mass of fine particles from laser printers and new Micro Piezo technology ink jet printers during the printing process and one hour afterwards as these emissions have potential for negative health effects.Air samples were taken with the particle size spectrometer for real-time ELPI+, Dekati (air flow rate 10 l/min). Measurements were taken ~0.5 m from the printers: one hour before the test, during printing and one hour afterwards. Similar class blackwhite (b/w) and colour printer of each technology were tested. Each printer performed a 10-page and a 100-page test according to ECMA 328-1 Standard [1].During laser printer tests from 8324 to 19943 pt/cm3 fine particles were determined on printing phase from b/w and colour printers. Ink jet (Micro Piezo) printers produced less: from 3239 to 5247 pt/cm3. One hour after the printing phase for both types of laser printers’ there were 54722 to 152351 pt/cm3 particles in air and 4270 to 9579 pt/cm3 particles for ink jet printers. Detected particle mass differences was insignificant: in range of 0.002 to 0.012 mg/m³ for laser printers and 0.002 to 0.019 mg/m³ for ink jet printers. Micro Piezo technology printers emitted mass particles were with bigger median size μm.The highest number of particles was observed one hour after the printing for both tested printer technologies. Laser printers’ emitted 2.5 to 3.8 times more particles in printing phase and 12.8 to 15.9 times more after printing phase. Particle mass in mg/m³ was detected in the size range 6nm - 2.5 μm with no significant mass differences.

The Possibility to Recreate the Shapes of Objects on the Basis of Printer Vibration in the Additive Printing Process

Information protection is an important safety issue in many human activity fields. Technological advances and related ubiquitous computerization bring new challenges in this area. In particular, the problem concerns the protection of devices against non-invasive acquisition processed information in ICT systems. It is known that, e.g., VGA, DVI/HDMI interfaces or laser printer formatter systems that process visual signals are the effective sources of compromising electromagnetic emanations. The emission safety of the more and more commonly used 3D printers is less known. In many cases, the disclosure of information about printed objects might constitute an infringement of the state/industrial/commercial secret, copyright, patent protection, etc. In order to analyze the existing threat, a selected printer using FDM technology was tested. During the tests, simple objects were printed to identify the operation of the stepper motor and the movements of the printer head and the printer platform, which are sources of emissions in the secondary channels. The analyses performed focused on finding the correlation between the recorded vibration signals and the printer head movements when an object was printed. It was shown that the analysis of the registered sensitive signal runtimes and their spectrograms allowed to recreate the printed object shape. Three simple objects (a trihedron, a tube and a tetrahedron) were selected for testing because they include elements that allow the four major movements of the printer head to be easily recognized: along the X axis, along the Y axis, along an arc and diagonally (between the X and Y axes). The paper presents the test results and their analyses.

Visible-light-driven hydrogen evolution from waste toner powder activated by Ni species

With dramatically increased application of modern office equipment like laser printer and photocopier, large amounts of waste toner powder were yielded, discarded and ended up in landfills around the world...

Analiza SEM czarnego tonera na wydrukach. Część II

Eksperci w zakresie badań dokumentów są często proszeni o określenie, czy wydruk pochodzi z określonej drukarki laserowej. Drukarkę rzadko można zidentyfikować, chyba że na wydruku są widoczne jej unikalne wady lub nieprawidłowości. W artykule przedstawiono możliwości identyfikacji i weryfikacji tonerów na wydrukach uzyskanych z rożnych drukarek laserowych przy użyciu skaningowej mikroskopii elektronowej. W sumie 21 wydruków uzyskano z 21 rożnych modeli maszyn drukujących Brother i Konica Minolta. Szesnaście wydruków uzyskano z drukarek, w których były oryginalne kasety z tonerem, a pięć z drukarek z zamiennikami. Ustalono jasne kryteria oceny indywidualnej. Na podstawie zdjęć SEM oraz tych kryteriów ujawniono szczegóły topografii struktury tonera. Na podstawie przeprowadzonych badań określono różnice lub podobieństwa tonerów na badanych wydrukach. SEM analysis of black toner on printouts. Part II Document examiners are frequently asked to determine whether or not a printout originated from a particular laser printer. The printer can rarely be identified unless some unique defects or irregularities of the printing are present on the printout. This article presents an overview of a systematic approach to characterizing and discriminating the toner of different laser printers using scanning electron microscopy. A total of twenty-one collected printouts were printed on twenty-one different Brother and Konica Minolta printing machine models. Sixteen printouts were obtained using printers with original toner cartridges while five printouts were obtained using printers with compatible cartridges. Clear criteria were established for individual assessment. Based on the SEM images and established criteria the details of topography of the toner structure were revealed. Due to this study, the differences or similarities of toners on tested printouts were determined. The SEM technique can be successfully, simply, and rapidly applied to the analysis of toners on paper documents.