Applied Mechanics and Materials Vols. 687-691

Abstract: This paper proposes a novel finite-time consensus tracking protocol for guaranteeing heterogeneous multi-agent systems with a virtual leader to achieve the fast finite-time consensus tracking. The Lyapunov function method, algebra graph theory, homogeneity with dilation and some other techniques are employed to prove that heterogeneous multi-agent systems with a virtual leader applying the proposed protocol can reach the finite-time consensus tracking. Numerical simulations indicate that compared with traditional finite-time consensus tracking protocols, the proposed protocol can accelerate the convergence speed of the finite-time consensus tracking.

Abstract: In the process of long-term storage, the equipment would happen storage environment contaminated corrosion, mechanical structure stress corrosion damage. Currently,the corrosion fatigue damage prediction accuracy of method was low. Different kernel functions were adopted by this paper to compare based on least squares support vector machine (LSSVM). Besides, comparison was made among the BP neural network method, Standard Support Vector Machines (SVM), Grey System Prediction model Method and the radial basis function kernel least squares support vector machine (RBF_LSSVM) method by the simulation experiment. The optimal results finally were applied to practical engineering. The results showed that high accuracy and performance could be gained by employing the RBF_LSSVM method for predicting the trends of the mechanical structure rivet corrosion.

Abstract: Horizontal support extending loader vehicle is used in coal mine, whose main role is to play a supportive role in belt transport unit. When the support car is pulled by tractor or pushed by motor vehicle, energy consumption is high with its own excessive weight. The car lightweight design is carried out through structural designing and material changing. Lightweight design has met the requirements after analysis. Lightweight design for support vehicle is not only to achieve the purpose of energy conservation, but also make the support vehicles assembling easily and get a good effect.

Abstract: In this paper thermal simulation of a satellite borne electric box is introduced. Structure was simplified and a finite element model was built. The analysis results showed that the temperature scopes of the box and the component cases are from 45°C to 67.3°C and all of junction temperatures of the components are lower than the derated maximum junction temperatures themselves and leave enough design margins, which match the requirements of thermal analysis.

Abstract: In this paper, we propose an efficient numerical method for ordinary differential equation with fractional order, based on Legendre-Gauss-Radau interpolation, which is easy to be implemented and possesses the spectral accuracy. We apply the proposed method to multi-order fractional ordinary differential equation. Numerical results demonstrate the effectiveness of the approach.

Abstract: In order to establish a reasonable mathematical model, closer to the real situation, we must first establish an ideal situation without disturbance model under. However, in the actual situation of the projectile is not possible, it will be affected by the initial disturbance and the effect of random wind field, this paper focuses on the impact of wind field spread of projectile trajectory.

Abstract: High-dynamic flight simulator (HDFS), using a centrifuge as its motion base, is a machine utilized for simulating the acceleration environment associated with modern advanced tactical aircrafts. This paper models the HDFS as a robotic system with three rotational degrees of freedom. The forward and inverse dynamic formulations are carried out by the recursive Newton-Euler approach. The driving torques acting on the joints are determined on the basis of the inverse dynamic formulation. The formulation has been implemented in two numerical simulation examples, which are used for calculating the maximum torques of actuators and simulating the time-histories of kinematic and dynamic parameters of pure trapezoid G_z-load command profiles, respectively. The simulation results can be applied to the design of the control system. The dynamic modeling approach presented in this paper can also be generalized to some similar devices.

Abstract: A time-optimal control of a 4RRR parallel manipulator with actuation redundancy is reported. A method using both redundant actuation and velocity planning is carried out to achieve the shortest moving time of the platform travelling through an assigned path without reducing precision caused by the backlashes in the actuators. The problem is simplified and an adaptive method of time-optimal control is designed based on the characteristics such as pre-coupling of time segments and decoupling of the redundant torques and time segments of this problem. The result demonstrates that this method can solve this problem with high speed. It serves as an example of both time-optimal control in robotics and multi-parameter optimization.

Abstract: Numerical Simulation of pulsating flow in a pulse combustor tailpipe was performed using computational fluid dynamics (CFD) method. The flow in the pipe was characterized by periodic pulsating. The influence of this pulsating includes incomplete flow development and high level of convective heat transfer rate, and both were considered and investigated by the CFD model. Compared with the steady flow condition, results showed that the heat transfer coefficient and Nusselt number were 2.35 times higher.

Abstract: The operating mode of the pulse combustor with the exhaust decoupler was summarized and discussed. Based on the earlier study of the nonlinear analysis of the system, the basic three modes were explained in detail. Furthermore, two limited modes were addressed. The analysis of the modes distribution and mode transition show that the high-frequency and antiphase (HA) mode was the better mode for the pulse combustor.