Applied Mechanics and Materials Vols. 130-134

Abstract: Polymethyl methacrylate (PMMA)/ acrylonitrile-styrene-acrylate terpolymer (ASA) alloy was prepared via melt blending method. Effects of ASA melt flow rate and PMMA/ASA ratio on mechanical property of the alloy were studied. It showed that when the high melt flow rate ASA was used, alloy’s tensile strength and flexural strength were little different from using low melt flow rate ASA, while the impact strength was significantly higher than the latter. Differential scanning calorimetry (DSC) analysis showed that a glass transition (T_g) platform emerged in low melt flow rate ASA at 48.5°C, which represented the T_g of the interface phase formed between SAN grafted acrylate rubber particles and SAN matrix. Scanning electron microscope (SEM) experiment further showed that when low melt flow rate ASA was used, alloy’s cross section was smooth which showed the characteristics of brittle fracture.

Abstract: In order to study the deformation characteristics of the blade rotor in the precision forming, by means of the plastic forming software DEFORM-3D, the forming process is simulated. It is concluded that (1) the change of the stress and strain in different stages was simulated during the entire forming process. (2) Based on the stress and strain distributions, the analysis of the metal flow rule and the mechanism of the filling mold was proceeded to find that the properties of the blade rotor can be enhanced by means of the precision forming.

Abstract: The hydrogels based on chitosan were prepared by Michael-type addition reaction between chitosan's primary amino groups and maleimide group terminating poly (ethylene glycol) (PEG) under mild conditions. The hydrogels were characterizatied by FTIR, TG, etc. The study on the swelling behavior indicated that the hydrogels possess pH-and thermo-sensitivity. The chitosan-based hydogels crosslinked by Michael-type addition reaction have a potential application on biomaterials due to its biodegradability, biocompatibility, less toxicity and hydrophilicity.

Abstract: TiO₂/Fe₂O₃ nanocomposite was fabricated by a hydrolysis-precipitation approach, with TiCl₄ as precursor and Fe₂O₃ as support. The crystal phase, diameter and morphology of the sample particle were characterized by X-ray diffraction, transmission electron microscope. The results show that the samples are composed of haematite and rutile. The morphology and diameter of rutile particle, coating effect and weight percentages of haematite and rutile are related to the preparing temperature and molar ratio of Fe/Ti. The photocatalytic activity of the prepared photocatalyst was estimated in an aqueous solution at ambient temperature of 303K. The results imply that the photocatalytic activity of the sample is higher than that of phase pure rutile, related to Fe/Ti molar ratio and its preparing temperature. These results can be attribute to the microsturcture of the sample. A synergistic effect exists between titania and haematite in the nanocomposite.

Abstract: Hatching systems requiring high control accuracy of temperature and humidity. Particularly temperature, small temperature change will significantly affect hatching time and hatching rate；and temperature and humidity is the controlled amount of interaction between two. Due to the coupling characteristics of temperature and humidity is difficult to establish a precise mathematical model, caused uncertainty in its control. Fuzzy control method witch proposed in this article will not only improve control precision, and to improve the robustness of control algorithms and adaptive capacity.

Abstract: In view of the heavy workload and possible intervention to the normal traffic flow during the performance testing of road traffic signs, this paper is designed to present a system that can be installed in an automobile and automatically track and analyze the performance of traffic signs. The system consists of a carrying vehicle, GPS, IMU, area-array cameras, frame grabbers, data acquisition software and data analysis software. Based on close-range photogrammetry technology, the system is designed with a set of effective road traffic signs automatic detection algorithms, which can automatically measure and analyze the properties of road traffic signs, such as dimensions, headroom and verticality of the column, etc.

Abstract: This paper introduces a mobile robot developed for replacing battery of electric vehicle automatically and intelligently. The developed robot based on a modular concept has four different parts, including mechanical system, control system, detecting device and driving module. The mechanical system driven by AC servo motors and controlled by control system has four degrees of freedom, and adjusting movements are independent and accurate. All measures enhance its reliability and reduce the EV charging time. This paper introduces the different parts and advantages of this charging mechanism.

Abstract: In this study an online monitor and control system was developed and tested based on virtual instrument environment for combine harvester automation. A data acquisition system and control elements were integrated into a self-propelled combine harvester. The following online information was recorded: performance parameters (threshing drum torque, engine speed, operation speed, etc), machine settings (reel speed, knife speed, drum speed, etc) and guidance information. The collected data were integrated into windows-based software for real-time processing. Image sensing information was used for swath detection and obtained results could be transmitted to the actuator for auto steering. The guidance error could be controlled in the range of 0.15 m during road surface test with centerline. The ground speed was adjusted by using the threshing power consumption data to improve work performance during field test. Experiments results indicated that it was possible to use virtual instrument environment based system to monitor operation data and conduct other real-time applications for field operation.

Abstract: A laser navigation system is designed to guide the weeding robot，so that the robot can complete the weeding work according to the fixed direction. The laser launching module is fastened in the guiding destination, including laser modulation circuit and a laser source. There is a photoelectricity detector in the front of the weeding robot, composing of photocells array and multichannel gathering circuit. Laser launching device communicates with the robot by wireless send-receive module. The photoelectricity detector detects the position of the light spot when the laser coming from the laser launching device shines photoelectricity detector, then the ARM can calculate for the robot’s position information which will guide the robot moving straightly to the destination automatically.

Abstract: Ultrasonic flaw detection in weld inspection is commonly used in non-destructive testing methods. But when the ultrasonic inspection of the welds, point location of defects and identify need technical personnel calculation and according to their long-term practical experience, it requirement for inspection personnel has higher technology.And in ultrasonic weld inspection there will be some factors affecting the accuracy of positioning. It will lead to limitations of ultrasonic weld inspection. To solve these problems effectively, AutoCAD will be used in ultrasonic weld inspection.