Advanced Materials Research Vols. 201-203

Abstract: One of the main reasons on Flexible Coordinate Measuring Machines’ (FCMM) less application is that its accuracy can’t meet the practical requirements. The spatial error distribution model of FCMM is build using Support Vector Regression (SVR) method. The test shows the data from the model can effectively fit the samples, and arguably the model based on SVR is feasible. The novel method gives an idea of studying the spatial error distribution model of FCMM. Futhermore, the model can provide reasearch foundations for definiting optimal measurement area and thus help to improve the measurement accuracy in the next work.

Abstract: In order to verify the performance of the designed temperature controller of the plastic extruder using supercritical CO₂, we developed a Hardware-In-the-Loop (HIL) simulation system based on Matlab/Simulink RTW. In this platform, data transmission between real process and Matlab workshop was carried out by the data acquisition cards supported by xPC Target, so that the physical system was integrated to the simulation loop, and the system modeling, analysis, digital simulation and target downloading were all realized. The result showed that the designed temperature control algorithm had better effect when used in the plastic exturder production field. This HIL simulation system can shorten the development cycle and cost, improve the design level of the control system, and provide a solution to the demonstration of the controller in the real-time mode. What’s more, this simulation system can be applied in other process control fields as flow, pressure, etc.

Abstract: AdaBoost algorithm can achieve better performance by averaging over the predictions of some weak hypotheses. To improve the power of classification ability of AdaBoost, an infinite ensemble learning framework based on the Support Vector Machine was formulated. The framework can output an infinite AdaBoost through embedding infinite hypotheses into a new kernel of Support Vector Machine. The stump kernel embodies infinite decision stumps. At last, the algorithm was used in fault diagnosis for analog circuits. Experimental results show that infinite AdaBoost with Support Vector Machine is superior than finite AdaBoost with the same base hypothesis set. The purpose of enhancing classification accuracy of AdaBoost algorithm is achieved.

Abstract: Galileo system is a new satellite navigation system. In this paper, a Galileo signal receiver based on W phase detector is presented. It can capture and track the Galileo signals. Moreover, it can also reduce location errors caused by the multipath signal when the delay is just small chip length away from the useful signal. At first, the principle of the traditional E-L phase detector and its anti-multipath performance is analyzed in this article. Finally, the forming method of the W phase detector waveform is introduced.

Abstract: This paper introduces the structure and work principle of a two-coordinate precision magnetic stage. “The same plane” mode and magnetic driver is adopted, on the basis of analytical field, and response simulation is finished. The experiments result expresses that the positioning accuracy of the magnetic stage reaches nanometer accuracy.

Abstract: Fuzzy control methods are widely used in Adaptive Cruise Control System as time passes by,but there are also various limitations for its membership and fuzzy rule acquisition, over-relying on experts’ knowledge. This paper presented one Sugeno method based on Mamdani using ANFIS(adaptive network-based fuzzy inference system)with optimized its memberships and training processes. Its experimental results revealed that it can be embeded into ACC much more appropriately and efficiently.

Abstract: In order to improve the performance of networked control system which has the characteristic of uncertain time delay, predictive control is adopted. The model of networked control system is analyzed. Take into account uncertain network time delay caused by various factors and problem of model mismatch, predictive controller is designed and simulation model of system is built using software of Matlab. A method of reducing model mismatch is proposed. Study results show that predictive control can make networked control system with good performance.

Abstract: This paper analyses the construction mode and the structure composition of hardware and software of networked virtual test system; explores solutions and realization technology for LabVIEW-based networked virtual test; carries out researches on remote control technology of networked virtual instrument; develops the networked virtual data acquisition and processing system based on LabVIEW; realizes the acquisition, transmission and processing of remote data as well as the remote control of the running state of virtual instrument.

Abstract: According to the demand of data acquisition in power system, the intelligent wattmeter is constructed, which is based on DSP and FPGA as the data acquisition and processing system, meanwhile, the administration center of the intelligent wattmeter is based on single-chip computer 8051. With these, high speed, multi-point sampling, a large quantity accumulation and real-time calculation are realized. At the same time it reduces the effect of the measuring accuracy upon higher harmonic and the measuring accuracy could reach to 0.02 grade.

Abstract: Compensation effects of the active power filter based on PWM converters are mainly affected by two factors: ① time lagging of reference compensation current; ②The dynamic limit of switching device themselves, that is, the limit of max di/dt of filter power output. This paper has presented the error models which are used to evaluate the compensation errors of the two main limitations, and has studied various factors influencing the di/dt capability of converters by the experiments. The experiment results showed that the accurate compensation error models are different when the structure of the converter, the load type and the current controlling way are distinct. But the research work can be done by the similar methods: the size of the compensation errors can be determined by the actual compensation current curves, the area between average lagging reference current curves. Further more, the ideal compensation current can be observed as time function. Finally, the paper has verified the validity of the estimation error model by the experimental study changing the circuit parameters.