Papers by Keyword: Infrared

Abstract: In the study of excavator automation, the conventional contact-type sensors can be easily damaged because of the collision or vibration when measuring the posture of excavator’s manipulator. For this case, a novel vision-based approach for measuring the posture of excavator’s manipulator is proposed. In this approach, an industrial camera with an infrared filter is used to grab the perspective images of the manipulator under the irradiation of a LED infrared light source; and saddle point detection is adopted to detect the man-made targets which fixed on every arm of the manipulator. Then the selection algorithm based on the fixed geometric dimensioning between two targets is optimized to select the saddle point in targets, and the posture angle of the corresponding arm can be derived from the saddle point coordinates. Furthermore, the detection regions are tracked by anticipating the three group targets’ movement separately. Experiments show that with the infrared device, the vision-based posture measurement system of the excavator’s manipulator can better adapt to different illumination intensity conditions; and the optimization of target selection algorithm reduces the false detection rate from 4 times in every 30s to 1 time in every 30s; also, the average processing time for every manipulator movement frame is reduced from about 70 ms to 50ms by tracking the detection regions separately.

Abstract: Quantitative measured values for absorption of copper and its alloys are jet unknown in the temperature range between 30 °C and 500 °C which has to be passed before material melts in the initial phase of laser beam welding. Thus this paper investigates temperature and wavelength dependent absorption for VIS and IR wavelengths. For this purpose specimens of copper and copper alloys are heated up and reflected laser light from the surface is measured by using an Ulbricht sphere in combination with a photodiode. During welding processes inert gases are in use to reduce oxidation. Hence the influence of shielding gases on the absorption will also be taken into account during the heating process of the specimens. Consequently this paper provides results for the temperature dependent absorption of copper and copper alloys for different wavelengths at atmospheric conditions and argon shielding.

Abstract: The reflected radiation significantly negatively influences the results of the quantitative infrared thermographic measurement in the exterior. The paper deals the method of elimination of reflected radiation using appropriate equipment including examples of practical results of measurements.

Abstract: Verification of reach of grouting masonry using infrared thermography. Chemical grouting masonry is a progressive, modern restoration technique. Verification of reach (efficiency) of injection media by nondestructive methods have not been established and verified, yet. The article deals with the presentation of the results of the pilot thermography measurements.

Abstract: It's a type of wheeled robot based on the AT89S52 MCU, through the body and infrared emission source docking judgment target position, the differential signal to control the motor speed to improve the direction; used ultrasonic obstacle avoidance module continuously detect the front object distance; used the error compensation principle of probability and statistics on the mechanical arm debugging and correcting, so that the system may realize to the target automatically crawl.

Abstract: A three-dimensional physical and mathematical models of the heat transfer in the furnace specimen with an internal defect were established. Combined with the theory of infrared thermographic temperature measurement, using the L-M method, the inverse heat transfer problem of the boiler furnace wall bricks with crack was investigated. The size of defect was accurately estimated. Conclusions can be drawn by computational analysis, firebrick played a major role in the furnace thermal insulation effect. When firebrick fails, the inspection surface temperature is abnormal, and the temperature difference between the outer surface of the defect and that of the normal wall is an exponential relationship with the increase of defect depth.

Abstract: Irradiation induced complexes of C-rich case in silicon crystal were examined by the highly sensitive and accurate infrared absorption spectroscopy. Low impurity concentration and high quality crystal was used and low dose was employed to make the reaction simple. Almost all possible absorption lines were revealed and their absorbance determined. The conversion coefficient from absorbance to the complex concentration was estimated by the plausible assumptions. The reaction was discussed in terms of concentration rather than absorbance. Intra-group reaction, chain reaction of successive addition of oxygen or self-interstitial, reaction yield and competition between the parallel reactions were described.

Abstract: In the chemical engineering territory, the important parameters regarding reaction are fundamentally temperature, pressure, and concentration, among which the setting and monitoring of reaction temperature are crucial to complete the reaction efficiently, safely, and quickly. MOF Synthesis, due to the different heating pattern or unstable heating, usually affects the rate of nucleation and crystallization, causing the difference of crystalline. For the temperature sensing module made in this system, to ensure the reliability, this project implements the monitoring with wireless ZigBee chip and wire DAQ data acquisition card. The terminal interface sends the control package to infrared emission module through RS-232, and the signals are sent to infrared receiving module through infrared emission module to implement the automatic control of heating oven. The practical results are: (1) complete the temperature sensing module made by J type thermal couple, (2) ZigBee wireless and DAQ Data Acquisition Card wire transmission technology, (3) completing the development of infrared receiving and emitting control module, (4) the interface designed for this system covers the functions, such as monitoring, controlling, and recording, (5) Remote monitoring and control implemented with internet, (6) MOF synthesis heating experience.

Abstract: The Micro-bridge structure pays an important role in the mechanical support, thermal isolation and electrical connection for the UFPA detector, the quality of which has a direct effect on the imaging performance of the UFPA detector. A kind of Micro-bridge pixel is provided in this paper with thick-film pixel size of 360μm×360μm and desk-type adiabatic frame support, and the analysis results by FEM show that the minor thermal conductivity G and high responsivity can be obtained.

Abstract: A thick film array of high sensitive UFPA detector, with 16×16 units, is described in this paper. A micromachining capacitive pixel structure of infrared detector is provided, with the doped (Ba, Sr) TiO3 (BST) thick film as sensitive material. The key factors that affect the detector performance are described, and the basic physical and electrical parameters of ferroelectric materials that the detector needs are given. In addition, the heat insulation technique and the corresponding parameters are provided. The capacitance increment of pixel for this structure is approximately equal to that of infrared detector with equivalent sensitive area, and then the parasitic capacitance between the pixel and substrate electrode lead is reduced. It is easy to design the integrated circuit because the infrared detector with this structure needs only low precision for the circuit. This design idea for array structure of infrared matches the development trend of structure design of infrared focal plane pixel with large array, which paves the way to develop new UFPA detector.