Advanced Materials Research Vols. 466-467

Abstract: Needing to analyse fragment’s destructive effect for military researching purpose, it is produced after armour-piercing warhead penetrate target. How to reduce physical test expense and acquire believable researching result at the same time have been puzzled problems that must be solved as soon as possible. Discussing techniques of fragment produced in armour-piercing warhead penetration process with the way of numerical simulation based on AUTODYN, it is a program that analyses dynamics in this paper. Techniques mainly include the Lagrange, the SPH, the Lagrange combining with the SPH and the Lagrange combining with restriction invalidation, at the same time, analysed different technique’s merit and demerit by establishing the numeric simulation model of armour-piercing warhead destroying target and obtaining simulation result. By researching the technique of making numeric fragment, establishing favorable base for researching armour-piercing warhead destroying mechanism.

Abstract: Parameterized FEM models of multi-layer target are established. Base on the models, the process of long-rod projectile penetrating multi-layer target with two different angles of incidence are carried out by means of FEM analysis program LS-DYNA and the influences of the incident angle and multilayer mediums are studied. The results show that when vertical penetrating the multi-layer target in vicinity of the free surface the projectile underwent large deflexion and eventually escaped from the rock layer and when oblique penetrating the target the projectile penetrated claypan layer, rock layer, grit layer and concrete layer in turn. Different mediums brought different influences on penetration effects. The models and results could provide reference for projectile design and efficiency evaluation.

Abstract: By building the velocity plus attitude matching mode for ship transfer alignment, we analyze the impact of different hull deformation angles to the performance of transfer alignment and give simulation results. The theoretical accuracy of GPS attitude determination network applied for ship hull deformation monitoring is proposed. According to the simulation results, the performance of transfer alignment after hull deformation compensation by the monitoring network is effectively improved compared to the one without compensation.

Abstract: 6-DOF parallel robot forward kinematics can be achieved by Newton-Raphson method with more accurancy, but the result depends on the offer of initial value. It can definitely calculate the result by genetic algorithm, however, more evolved algebra is needed to make it more accurate, and sometimes it hardly meets the requirement by concurrent control. This article points to use the result of genetic as the initial value of algorithm, and ultimately make use of iteration to complete the forward kinematics. High accuracy and speed are the main features of this calculation, and another one is interpreting from the implementation point of view, which is very practical and meet the concurrent control through experiment.

Abstract: A measurement system based on the magneto-resistive sensor is described and its error factors and influences are analyzed as well. A reasonable and simple approach is presented to compensate the measurement error from Magneto-resistive Sensor output. Firstly, the principle of the new method is illustrated. Secondly, the steps of the error compensation are introduced. Finally, the test is carried out, results are shown that the maximum angle value of deviation is no more than 2° and compensation method can be used in common measurement system based on magneto-resistive sensors.

Abstract: The shock absorber plays an important role in the properties of stability and riding comfort of the vehicle. A virtual model of a double cylinder hydraulic vehicle shock absorber is developed for motion simulation and stress analysis by SolidWorks software. The kinematic character of the shock absorber was simulated by using the virtual model. And the stress analysis result showed that the shock absorber had high liability. All the results can also be helpful to design the double cylinder hydraulic vehicle shock absorber.

Abstract: Aim at local optimal problem in the path planning of mobile robot by artificial immune algorithm, it is proposed that the improved artificial immune algorithm of mobile robot path planning. Based on artificial immunity algorithm, the potential function method of an artificial potential field is used in this algorithm, improving randomness of the initial population of the artificial immune algorithm, then the algorithm make initial population turn to evolutionary operation through crossover, variance and selection operator to get optimum antibody. The simulation results showed that this algorithm is easy to get the optimal path, at the same time, increasing the speed of the path planning, and the length of the optimal path planning is less 28.5% compare with the traditional immune algorithm.

Abstract: A combined iteration method of load identification method is presented concerning one type of structure with nonlinearity. The proposed method realizes the load identification of the nonlinear dynamical system by combining and iterating the finite element method and the active control method. The finite element models of nonlinear dynamical systems are firstly contracted into the simplified model to make up the controlled plant. Then under the selected control law, the controller is designed to produce the system excitation, namely the identified load. The validity of the load is finally checked through the response of the nonlinear finite element model. For a conical shell-belting combined system, the numerical study regarding the load identification demonstrates the validity of combined iteration method, which can plays a guiding role in the load identification of vibration test respecting aerospace structures, such as missile, aerospacecraft, aerospaceplane, rocket and so on, making great contribution to the development of the aerospace industry.

Abstract: Binocular recognition extracts bitmap information based on different viewpoints of two horizontal lines. If it is not appropriate enough to deal with the left and right images, the computation of two images' horizontal parallaxes and vertical parallax will bring on the error. This article proposes one kind of effective algorithm that adjusts the image to be right based on traditional displacement correction algorithm, and completes the image remodeling through the two pairs of matching feature points and detection of the correlation distances. Experimental results show that the method can adjust the horizontal and vertical parallax effectively, so that the displaying effect of the stereoscopic image achieves best.

Abstract: Traditional control models of BLDCM, in which only the internal parameters of motors are considered, have some shortcoming in smoothing the vehicle velocity. To achieve a better controlling capability, a velocity-current double closed-loop control system model for BLDCM of PEV is constructed on Matlab, in which the inner current loop is for quickly adjusting BLDCM’s actions, the outer velocity loop is for an optimized control of PEV’s speed. The results of a simulating experiment show that the new model has a good performance and a strong anti-interfere ability. Therefore, this model is applicable for designing and debugging of BLDCM in PEV applications.