Abstract: Based on back-stepping control design, adaptive control and least squares support vector machine theory, a new least squares support vector machine adaptive back-stepping control law was designed for strictly block type of feedback nonlinear systems control with uncertainties. Least squares support vector machine theory method to approximate a nonlinear function of uncertain nonlinear systems by analyzing the disadvantage of common back-stepping. New control law of the nonlinear systems is achieved without accurate mathematical model. The method overcomes the impact of the bounded uncertainties on the control system. On this basis, the system stability and convergence are proved by Lyapunov method. Simulation results indicate that the designed control law has strong robustness and adaptability, uncertainties that exist in the strict block feedback nonlinear systems.
Abstract: Aiming at the increasing demand of performance for industrial control, the industrial real-time Ethernet control system for high-speed control based on EtherCAT was presented. The principles and frame structure of EtherCAT were introduced. The system response time, EtherCAT cycle time and oversampling technology of achieving microsecond-order sampling were analyzed. By designing the experimental platform based on EtherCAT, The system response time, EtherCAT cycle time and oversampling performance were tested. Theoretical analysis and experimental test results show that the System can achieve millisecond-order response time and microsecond-order oversampling cycle time. Therefore, Industrial Ethernet control system based on EtherCAT is very suitable for high-speed control and real-time data acquisition.
Abstract: Root-tuber crops are buried under the ground, thus, the mechanization harvest should apply digging method. However, the row-aligning angle of the shovel can directly influence the digging effect. Therefore, a set of auto-aligning technological equipments were designed to solve this problem and achieve aligned digging. This paper mainly analyzes the design of above mentioned equipments as below: A right-left angular displacement sensor is added in the front part to achieve auto-induction and signal transformation of the digging angel through comparison of the pressure angle. The adjustment of the control equipment can be achieved by the adjustment of signal when it goes through magnetic exchange valve. And with the help of cross slide way, the digging harvest machine can modulate the shovel timely and efficiently. Experiments demonstrated that such auto-row-aligning equipment can improve the digging effect.
Abstract: Performing the CORBA-based CIS (Component Interface Specification) services of IEC61970 is an important part in integrations of power automation system applications. Because of high requirement of the reliability and continuity in power automation system, implementing online standby running modules by CORBA-based software is becoming an indispensable function. This paper studies how to manage online standby running for the CORBA-based services on the basis of online standby management of SoftBus developed by iESLab. In this paper, two practicable ways to realize online standby running based on CORBA are presented and the difference between them is discussed in detail.
Abstract: Traffic identification using statistic features of traffic flows has attracted a great deal of interest. One challenging issue for these methods is that they ignore the short flows containing just 2-3 packets, for statistic features of short flows are mainly insignificant or meaningless. A topology-based method combining heuristic rules and deep-in packet inspection is proposed to identify the application types of traffic flows. The experiment results demonstrate that the method can get higher precisions and similar recalls compared to deep-in packet inspection method.
Abstract: This paper proposes a method to detect conductor defects in the field of modern non-destructive testing technology. A self-magnetic field induced by flowing current in the conductor is used in the detection technique, and a three-dimensional micro-displacement stage platform is used to scan the sample surface to obtain the self-magnetic field mapping of the whole sample. The subsequent data processing and imaging technology of the detection signal is also developed. To achieve precise positioning of the triaxial directions, an STM32 microcontroller (MCU) is used as the central processor to design the displacement control system, which communicates with a PC computer through the MCU system. The experimental results demonstrate that the stepper motor driving the magnetic sensor could run uniformly and that the proposed system has the advantages of smooth motion, low noise and high precision. As a consequence, the micro-displacement control system can be used to get a clear mapping of the defects in the sample.
Abstract: Based on the needs of TWACS (two way automatic communications system) the technical mechanism and digitize oilfield construction, this article designed and implemented a TWACS master facility which based on the work of the distributed structure to Meet well remote monitoring and management. Each 10KV line set DSP as the upstream demodulation unit platform in the master facility, which TWACS can detect the upstream signal from the 10KV line at the same time. Its feature has proved by field trials of the oilfield distribution network, and greatly improved efficiency of well remote monitoring.
Abstract: By describing a danger from driving vehicles with fog on windshield, we give a concept of a new type of automatic windshield defogging system applying traditional sensor and RBF neural networks. In terms of an analysis on the source of fogging on automatic windshield, applying traditional sensor, we design a RBF neural networks. Then, via RBF neural networks mode, training and testing 48 series of data from an experiment. A result of MATLAB software demonstrates that this new system defog from automatic windshield swiftly and precisely by applying RBF neural networks.
Abstract: Reducer’s input torque and output torque characteristics determine the kinematics performances of electro actuators. During the torque measurement experiment, many factors lead to torque measurement error, the major error components of which are mechanical assembly’s precision and electrical machine’s driven features. Compensating electrical errors and obtaining the real mechanical characteristics are meaningful and necessary especially on the conditions of wide-scale torque measuring. Neglecting mechanical factors’ influences, this paper pays attention to system’s control features based on the actual project with the demands of steady state and dynamic torque loading. Considering the quantized error, the mathematical model of power driven system is established, and the appropriate control algorithm of piecewise PID method is proposed, the simulation curves of which are expressed. The actual measuring experiment curves of rotating angle and compensated torque are drawn, the results of which illustrate the torque measuring error induced by drivers has been obviously removed, which validates the efficiency of such method.
Abstract: This paper proposes two types of adaptive control schemes combined by the conventional computed-torque control and different fuzzy compensators for the robust tracking control of robotic manipulators with structured and unstructured uncertainties. Fuzzy compensators based on feed-forward and feed-back are developed to compensate these modeling uncertainties. The validity of the two types of adaptive control schemes is shown by numerical simulations of a three link rotary robot manipulator.