Applied Mechanics and Materials Vols. 246-247

Abstract: Gas monitoring of roadway excavation of coal mine is of utmost importance, to monitor the gas distribution more effectively, the following works were carried out. Taking a rectangular tunnel as research object, the distribution law of the gas was simulated by using commercial software FLUENT, a simulation test bed was built according to similarity theory and sensors arranged according to simulation results to form a sensor network, BP neural network was adopted in process of acquired data. The results show that it is of accuracy and feasibility to provide theoretical basis for arrangement of the network sensor by simulation results of gas distribution. By using a BP network, the sensor network can be used to predict the gas concentrations accurately.

Abstract: In order to guarantee the belt conveyor reliable operation, it is necessary to find and ruled out the possibility of failure. This paper introduced the CAN bus technology and in its’ application use the CANopen protocol which is windly used in the internation to complete timely and effective monitoring of the switch.

Abstract: This article deals with the problem of dissipative control synthesis for a class of descriptor systems with uncertainties in the derivative matrix. Attention is focused on the design of a proportional plus derivative (PD) state feedback, which guarantees that the closed-loop system is robustly stable and strict dissipative. Firstly, a sufficient condition for the closed-loop system is robustly stable and strict dissipative is presented by using a simple idea of changing the problem to the corresponding problem of an augmented uncertain system. Then, a PD controller is constructed by solving LMIs. Finally, a numerical example is given to demonstrate that the proposed method is effective.

Abstract: Based on topological graph theory, collaboration technique and other relevant theory, this paper carry out the research of exploring a technical path to solving the conflict of concurrency in CVM, Under the circum stances of conforming to logic and topological relationship , the attributes of timing sequence are studied emphatically, following the deeply analysis quantitatively and qualitatively, then the mathematical expression of predicted retardation and the control strategy are put forward, which builds a fair and friendly negotiation mechanism for occurrence priority distribution. Finally the OOT (Object Oriented Technology) based programming structure and realization means of the strategy are given in this paper. What elaborated in this paper has certain engineering and application value for the design of complicated virtual maintains system , conflict resolution of concurrency and the application of collaboration technique etc.

Abstract: The brushless DC motor (BLDCM) non-linear and the complexity of the working conditions are likely to cause the conventional PID servo control performance is not satisfactory. In order to improve the performance of the BLDCM servo control system and PID parameter tuning efficiency, this paper designs an adaptive fuzzy PID controller. Fuzzy logic PID controller parameters Kp, Ki, Kd are adjusted online real time to achieve the effect of optimal control, the BLDCM speed is as to the control object, and in the Matlab of Simulink toolbox simulation is used to achieve speed closed loop of BLDCM. According to comparative analysis of the conventional PID and adaptive fuzzy PID of Dynamic response curve, adaptive Fuzzy PID quick start for brushless DC motors, anti-disturbance has better control effect.

Abstract: Master and slave manipulator has been widely used because it can work easily in the working environment where the human beings can hardly work. In order to make the manipulator control system have good tracking performance, a control strategy based on sliding mode control was proposed for master-slave manipulator control system. Considering that the quality and stability of servo system will be affected by the chattering phenomenon in the SMC, a reaching law approach was used to reduce the chattering phenomenon. The proposed control strategy can make the master and slave manipulator have good performances on force and position tracking, and the chattering problem has also been alleviated. Simulation and experiments results show that the proposed control strategy can produce good performances on the force and position tracking, the problem of chattering has also been inhibited significantly, and the stability and quality of the master and slave manipulator has been improved as well.

Abstract: This paper presents a Direct Yaw-moment Control (DYC) strategy to prevent light vehicles from entering the unsteady state and improve the handling stability. A novelty of this work is the ability to achieve superior performance through the lower workload of the actuators by using the optimal control allocation method to distribute the active yaw moment. In the main-loop, the DYC controller is designed based on the classical PID algorithm with the yaw rate and sideslip angle feedback. Simulation tests are carried out on the conditions of sine steering and single lane change steering. Results indicate that the working potential of each actuator can be fully utilized and a significant improvement in handling stability can be achieved from the DYC system.

Abstract: An autonomous formation-flight method for multiple UAVs (Unmanned Aerial Vehicle) was designed. First the mathematical representation of formation shape was analyzed. Then the control architecture was devised for multiple UAVs formation flight based on finite state machine. The flight states of the wing UAV were built through the formation flight and the transformation relationships of these flight states were defined. So the automated transformation among these flight states could be achieved and the intelligence of the pilots could be mimicked by this way. Aiming at the typical flight state which is capable of maintaining the formation shape, the control laws were contrived for the wing UAVs. Finally, two nonlinear fighter models which have 6 degrees of freedom were selected to carry out autonomous formation-flight experiments. And the results show the control laws designed for maintaining the formation shape are valid.

Abstract: Internal control evaluation is very useful to strengthen internal control, and to establish a scientifically target system is one of the key points of internal control. This article proceeds with the basic procedures of internal control, puts forward a target system, establishes a fuzzy comprehensive evaluation model based on fuzzy comprehensive evaluation, and people can utilize the model with some practical data of internal control in order to provide help for internal control evaluation.

Abstract: Synchronization of an uncertain dynamical network time-delay is investigated by means of robust control schemes. This paper is devoted to the robustness analysis of controlled complex network concerning the effect of communication delay and uncertainty, where the topology is not exactly known in the synchronized process. First, we analyze the synchronization error dynamical model of the uncertain networks concerning time-delay. Then, based on this system, we derive a sufficient condition for globally asymptotical synchronization of the controlled uncertain network without time-delay in terms of linear matrix inequality by using Lyapunov approach. Furthermore, we investigate robustness property of the controlled uncertain network affected by time-delay, and give a design criterion for the control to guarantee globally asymptotical synchronization. Finally, A simulation is provided to show effectiveness of our strategies.