Applied Mechanics and Materials Vols. 268-270

Abstract: RFID anti-collision technology is one of a key technology in RFID application system. Anti-collision algorithms for RFID systems include tag anti-collision algorithms and reader anti-collision algorithms. This paper focused on the impoved binary algorithm and dynamic binary algorithm. An improved algorithm has been proposed, in which the collision bits was put into the stack and they were used as the reader’s request. Based on this mechanism, a novel binary stack algorithm has been proposed. Its simulation was given to analyze the performance of this algorithm. The simulation results showed that the amount of transmitted data in proposed algorithm was obviously less than those in the other two traditional algorithms with the number of tags and their bytes increasing. Consequently, the performance of the proposed algorithm is much better than that of the traditional anti-collision binary algorithm.

Abstract: In order to increase starch yield, it is important to adopt counter-current steeping method and control the steeping temperature under limits which is appropriate for corn wet milling process. Firstly, the configuration of steeping temperature control system and steps of counter-current steeping for corn wet milling process is introduced in this paper. Secondly, the hardware design of steeping control system for corn wet milling process is developed. As a part of starch production DCS control system, a C/S structure which using industrial computer as upper computer and using S7-400 PLC as lower computer is adopted. Finally, the steeping temperature control program based on fuzzy-PID control and algorithm of automatic steeping is presented. The real-time operation shows that the control system given by the paper can meet the requirements of corn steeping production.

Abstract: The load on the cutting boom of roadheader changes violently because of the changes of rocks hardness. The power of cutter motor is related to the hardness of rock and propulsive force. The propulsive force is determined by the moving speed of cutting boom. The hydraulic control system of arcing cylinders is an electro-hydraulic proportional control system. The adaptive control model is build by Simulink. A PID control is used and the power of cutter motor is keep at a constant state by adjusting the speed of arcing cylinders.

Abstract: The fault detection and diagnosis system, which uses dedicated interface adapter unit and PXI interface modules to perform signal excitation and parameter testing, is introduced in this paper. Its firmware consists of PXI-bus control computer, display control unit, dedicated interface adapter unit, connection cable and power supply unit. The dedicated interface adapter unit (IAU) is the core of hardware platform, and is composed of chassis, I2C-bus data acquisition board, adapter and military aviation sockets. It carries out analog to digital, digital to analog, digital I/O transformation as well as serial communication and CAN-bus communication. The software of the fault detection system is of hierarchical modular structure with integration of system management control, fault detection and circuit hardware driver modules together with repair and diagnosis database. The software provides functions of human-machine interaction, equipment fault detection, fault diagnosis and analysis, repair guidance and data storage. Therefore, this system can implement fault detection of hydraulic excavator on replaceable circuit board and block of the hydraulic system or electrical system. And it can help equipment repairmen and operator perform quick repairs and maintenance to the electrical system and hydraulic circuit of the excavator.

Abstract: This article presents a method of controlling a mobile robot using the Mobile-C mobile gent combined with Ch and details of the Mobile-C’s structure. By the control of Mobile-C mobile agent, the robot can be dynamically switched to new algorithms at runtime to deal with unexpected situations. At last, the distributed application experiments prove the effectiveness of the robot control based upon the Mobile-C mobile agent approach.

Abstract: Magnetorheological fluid (MRF) Brake is a newly-developed intelligent brake in which traditional mechanical brake friction pairs are replaced by MRF materials and the electromagnetism devices are very important components. The controllable magnetic fields are generated by electromagnetism devices which can make MRF materials create related braking torque to control the braking performance of the MRF Brake. In this paper, the electromagnetism device consists of several coil sets which can generate electromagnetic fields for MRF Brake. By using finite element analysis, the magnetic fields generated by electromagnetism devices are compared analytically under the different conditions, and then the optimum parameters are obtained such as coil arrangements, excitation currents and air gap distances and etc. All these evidences are helpful to design the structure of electromagnetism devices in MRF Brake.

Abstract: Keller SYMPlus CNC is developed by Germany Keller software company, which has powerful simulation function of NC machining. Based on the current Keller software (version 5.1) can't simulate and machine noncircular curve ,only can machine circular arcs and straight lines.This article uses telescopic step method and double-arc method simulation noncircular curve, then impo- rts DXF into Keller, finally realizes the machining and simulation of parts with non-circle curve.

Abstract: Artificial muscle is a new style of actuator with novel working principle, which owns the advantages of compact structure, high power-to-weight ratio, compliance and easy application. Pneumatic artificial muscle (PAM) is usually used in robotics, medical auxiliaries and other small force output occasions nowadays. However, it suffers problems of small power, hysteresis and poor repeatability. A kind of artificial muscle working at high pressure was researched. Different muscle styles are compared and MicKibben structure is selected while fluid media is determined. Furthermore, factors of geometry and material properties, which limit the ultimate pressure, are analyzed. Formulas and simulations verify the influence of limitation and help to calculate key parameters of 18MPa artificial muscle. Data show that it is possible in theory to design high pressure artificial muscle by overall consideration of initial diameter, initial contraction angle and material properties, initial length only influent the stroke.

Abstract: Rotary ultrasonic machining(RUM) as a precise and efficient processing method for hard and brittle materials can be used for significantly improving processing efficiency, reducing the cutting force and cutting heat, improving the surface quality. Development of high performance RUM machine tools and equipments has been caused on widespread attention from the worldwide scholars. In this paper, the development of the RUM machine tools has been reviewed about the accessory RUM head and load matching system.

Abstract: The process optimization model was established in finish machining of the bottom surface of the integral impeller channels. The optimization objective was the maximal productivity, and three process parameters such as spindle speed, feed speed and cutter row space are chosen as design variables. Constrains were analyzed from three aspects: machine tool, cutter and machining quality in accordance with the actual 5-axis machining conditions. The genetic algorithm (GA) was employed to seek the optimum solution. A machining experiment was conducted to compare the efficiency of the optimum parameters with that of the empirical parameters. The results showed that the optimum solution reduced by 29.4% time in comparison with the empirical parameters, which represented that the process optimization was significant in improving the finish machining efficiency of impeller channels.