The Experts below are selected from a list of 6303 Experts worldwide ranked by ideXlab platform
Wenbo Zhang - One of the best experts on this subject based on the ideXlab platform.
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Reliability assessment with varying safety threshold for shock resistant systems
Reliability Engineering & System Safety, 2019Co-Authors: Yunxia Chen, Wenbo ZhangAbstract:Abstract The anti-shock Auxiliary Device is an important part to protect a shock resistant system from shock loads, and the damage degree and recovery state of the Device seriously affect the damage process and failure behavior of the whole functional system. In this paper, the concept of the varying safety threshold is proposed to represent the absorbing capability of the Auxiliary Device to time-varying shocks, and it is modeled by a piecewise function of two variables with shock magnitude and inter-arrival time. In addition, a reliability assessment model is proposed with the varying safety threshold. Furthermore, a numerical example using hydraulic control system (HCS) is conducted to demonstrate the effectiveness of our model. Finally, the effect analysis of different types of shock loads and the parameter sensitivity analysis are also discussed in order to improve the reliable life index of shock resistance systems.
F A Almeida - One of the best experts on this subject based on the ideXlab platform.
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a force impedance controlled industrial robot using an active robotic Auxiliary Device
Robotics and Computer-integrated Manufacturing, 2008Co-Authors: Antonio M Lopes, F A AlmeidaAbstract:A strategy to improve the performance of current commercial industrial robots is presented in this paper. This strategy involves cooperation of two robotic manipulators: the robotic controlled impedance Device (RCID) and a commercial industrial robot. The RCID is a small six degrees-of-freedom (DOF) high bandwidth force-impedance controlled parallel manipulator, developed at the School of Engineering of the University of Porto (Portugal). The RCID works attached in series with a position controlled commercial industrial robot. Combination of the two manipulators behaves as a single manipulator having the impedance and force control dynamic performance of the RCID, as well as the workspace and trajectory tracking bandwidth of the industrial robot. Force-impedance control of the RCID, and experimental results on typical tasks that involve end-effector contact with uncertain environments of unknown stiffness are presented.
Carlos Enrique Niño Bohórquez - One of the best experts on this subject based on the ideXlab platform.
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Ultrasound in arc welding: a review.
Ultrasonics, 2014Co-Authors: Tiago Vieira Da Cunha, Carlos Enrique Niño BohórquezAbstract:During the last decade, the introduction of ultrasound techniques in arc welding with the intention of improving the operational performance and technical characteristics of the welding processes have been studied intensively. In this work is presented a broad review of the literature surrounding the utilization of this technique. Firstly, we discuss the use of traditional mechanical transducers to generate ultrasound in arc welding. Furthermore, we describe the various methods and their application in arc-welding processes. After, is presented a recent method of introducing ultrasonic energy in arc welding, which forms a potential alternative to the use of traditional mechanical type transducers. This method was originally developed in the late 1990s and is called arc with ultrasonic excitation of current. Here, the arc acts not only as a thermal source but also as an emission mechanism for ultrasound, acting directly on the weld pool. We presented and discussed various innovative concepts based on this method, which allows the introduction of ultrasonic energy in the arc welding without the need of any Auxiliary Device of welding. In addition, we also presented the variations of this method reported in the literature. Finally, we have described the respective effects attributed to the use of this method in the welding of different materials using various welding processes.
Xin Yong - One of the best experts on this subject based on the ideXlab platform.
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Influence of Process Parameters in Rapid Heat Cycle Molding on Replication Capability of High-Gloss Surface Parts
Polymer Materials Science and Engineering, 2010Co-Authors: Xin YongAbstract:By integrating a high-gloss surface mold for front panel of mobile door key and an Auxiliary Device for controlling the mold temperature, which had been developed and manufactured independently, the influence law of process parameters in rapid heat cycle molding on replication capability of high-gloss surface plastic parts was investigated. The experimental results show that Rapid Heat Cycle Molding (RHCM) technology can ensure much higher replication fidelity of part to cavity than conventional injection technology with higher mold temperature maintained at filling and packing stage, as well as rapid cooling of cavity at cooling stage. Pressure and temperature factors were more significant on replication fidelity of part than time factors, which are slight impacts on it. Compared with conventional technology, higher melt temperature and injecting pressure are needed to keep filling completed in rapid heat cycle molding, and packing time on replication fidelity is obviously increased. The experiment has also studied the change of runner system weight with change of parameters, and the results reveal that it is feasible to enhance the replication fidelity remarkably by increasing process temperature.
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Influence of Mold Temperature in Rapid Heat Cycle Molding on Shrinkage of Plastic Part
Polymer Materials Science and Engineering, 2010Co-Authors: Xin YongAbstract:By integrating the mold for front panel of mobile key and Auxiliary Device for controlling mold temperature,which was developed independently,the influence law of mold temperature in rapid heat cycle molding on shrinkage of part was investigated. This research also studied on other parameters influencing on shrinkage with fixed or changed mold temperature. The results reveal that the most significant influence of mold temperature on shrinkage is it would be decreased apparently,when it is set on higher than the thermal deformation temperature of polymer. Temperature factors and pressure factors are more important on shrinkage,while time factors have no obvious effects. With increase of mold temperature,part shrinkage would be decreased by a small margin with same melt temperature or injecting pressure,while it would be fluctuated as a "V" shape within a narrow range with same packing pressure,packing time or cooling time.
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Influence of mold temperature in rapid heat cycle molding on replication capability of plastic parts
Materials Science and Technology, 2010Co-Authors: Xin YongAbstract:In order to further investigate the influence of mold temperature in rapid heat cycle molding on the replication capability of plastic parts,a vehicle-used high-gloss blue tooth mold and an Auxiliary Device for controlling the mold temperature were employed in experiments,which had been developed and manufactured independently.The influence law of other process parameters on the part replication capability under changed mold temperature conditions as well as the changing law of other parameters with mold temperatures under the same product quality was studied.The results reveal that the part replication fidelity will be improved apparently when the mold temperature is risen to approach the thermal deformation temperature of polymer material.Temperature and pressure have obvious effect on the part replication fidelity,while time has little effect on it.With the increasing mold temperature,the part replication fidelity will be improved by a small margin under the same melt temperature and injecting pressure,and it will fluctuate as a "V" shape within a narrow range under the same packing pressure,packing time and cooling time.
Yunxia Chen - One of the best experts on this subject based on the ideXlab platform.
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Reliability assessment with varying safety threshold for shock resistant systems
Reliability Engineering & System Safety, 2019Co-Authors: Yunxia Chen, Wenbo ZhangAbstract:Abstract The anti-shock Auxiliary Device is an important part to protect a shock resistant system from shock loads, and the damage degree and recovery state of the Device seriously affect the damage process and failure behavior of the whole functional system. In this paper, the concept of the varying safety threshold is proposed to represent the absorbing capability of the Auxiliary Device to time-varying shocks, and it is modeled by a piecewise function of two variables with shock magnitude and inter-arrival time. In addition, a reliability assessment model is proposed with the varying safety threshold. Furthermore, a numerical example using hydraulic control system (HCS) is conducted to demonstrate the effectiveness of our model. Finally, the effect analysis of different types of shock loads and the parameter sensitivity analysis are also discussed in order to improve the reliable life index of shock resistance systems.