Applied Mechanics and Materials Vols. 644-650

Abstract: High effective vision system is important for autonomous driving vehicles. A panoramic vision system based on FPGA+DSP with 6-camera for intelligent vehicles is presented in this paper. The system includes digital image acquisition module and high image processing module which work independently to each other. The including two C6416 DSP chips and one high-performance Virtex-4 FPGA to achieve the complex real-time image processing during autonomous driving, such as cylindrical panoramic image rebuilding, lane detection and tracking. The proposed algorithm was also optimized according to the specific characteristics of the hardware for high parallel processing in FPGA and pipelined in DSP.

Abstract: Based on WNN, an improved model of High Voltage Switchgear temperature prediction is built. The model is optimized with hard threshold de-noising with wavelet package analysis, made an ultra-short term prediction loosely combines Elman neural network. However, the characteristics of the original signal are reserved and the noise interference is mostly eliminated. The experiment results show the processed sample as input one improves the prediction accuracy of Elman Network and reduces the root-mean-square error. And the prediction values show good coincidence to the measured ones that improves the reliability of early warning.

Abstract: It is inevitable that the mechanical part has error when machining. To increasing the machining precision and decreasing the shape and position error, error compensation is one way. The geometry error parameter is necessary when the error compensation model is founded and the compensation data is calculated. The common measuring and identifying methods are introduced in this article. Their mathematic models and solutions are listed and their merits and drawbacks are compared. This method has been applied in CNC error compensation and the effect is advisable.

Abstract: The high precision synchronized multi-axis control has become one of the key issues in modern manufacturing industry. As synchronized multi-axis control systems are nonlinear, time-variable and easily affected by disturbances, it is difficult to determine reasonable coupling control law and large amount of on-line calculation just through the existing synchronous control strategies for multi-axis system. In this paper the development status of multi-axis control synchronization control strategy is analyzed and the synchronization control algorithm is proposed based on the adjacent coupling error. The parameters of cross-coupled control are set on the basis of BP neural network control theory, which can not only reduce the tracking error, but also eliminate the synchronization error between adjacent axes. The synchronization performance of this approach is good with simple configuration. With this approach, the synchronization performance is good with simple configuration. Simulation results of the multi-axis synchronous system show that this method can effectively obtain the synchronization with a quick convergence. In the end, the multi-axis cross-coupled control approach based on BP neural networks is applied to a three-axis synchronization control system and its effectiveness is discussed.

Abstract: A nonlinear decoupling control method based on back-stepping design and sliding variable structure control theory was proposed in this paper according to the nonlinear and strong coupling characteristics of missile at hingh angle of attack. The affine nonlinear model of missile was firstly established, the exact linearization and input/output decoupling of system were then realized using differential geometry theory. On the basis of this, the robust controller was designed using back-stepping design and variable structure control method. Simulation results indicate that the influences caused by missile parameter uncertainties, unsuited uncertainties with known upper boundaries and stochastic interference can be effectively restrained.

Abstract: In the wrapping process of magnet wire, as the haulage speed of master motor varies periodically, it is difficult for slave wrapping motor to track master motor due to the mechanical resonance, which destabilizes the wrapping pitch. In the proposed system, the synchronization speed control scheme of master-slave motor based on repetitive control compensation is employed. In the process of control, real-time spectrum analysis of the haulage speed is given, which can be used to adjust the parameters of wrapping speed controller adaptively with the acquired characteristic information of the mechanical resonant. Simulation shows that wrapping speed can track haulage speed well in the proposed system, and the maximum tracking synchronous deviation can be reduced to 56% of that in the system without repetitive control.

Abstract: The water tunnel and wind tunnel test carried on the arrow aims to have a better understanding of the hydrodynamics performance of arrows and to improve the technical knowledge of the archery movement Through the experimental research, we can draw conclusions as follows: within the range of angle of attack ( -6°---6°), the arrow can keep the state of attached flow: The state of flow of the arrow with spiral plastic pinna is better than that of arrow with straight one; Within the experimental angle of attack, the lift coefficient Cy will become larger with the pitching moment coefficient Mz getting smaller with the increase of the angle of attack. The arrow has the vertical static stability; with or without arrow feather will have great impact on lift force Y and pitching moment coefficient Mz; the feather rolling will have some impact on lift coefficient Cy, The arrow feather is the main components to produce lift force Y and to give the arrow body relatively great static stability.

Abstract: In low-stress precision cropping, a method by which the tiny crack in metal bar V-shaped notch tip can be induced by resonance has been proposed. The critical loading acted on the bar is obtained. The amplitude of bar is calculated under the action of critical loading. The experiments for resonance inducing V-shaped notch tip crack is also carried out. The results show that the V-shaped notch tip can engender tiny crack under the action of resonance force.

Abstract: In recent decades, with the acceleration of population flowing in China, large and medium-sized cities to speed up the construction of urban rail. Relatively high speed railway, the requirement of the urban rail is relatively low, so it can be designed on the basis of high speed railway track structure for urban rail transport, this gives the designer the design of large space;Each city urban rail structure more or less differences. Especially fastening system is various, even in the same line also exist different fastening systems.Because Chinese fastening system in the subway is various, not a fixed is widely used fastening system;This paper, the DT series fastening in subway system has carried on the simple summary. Make a reference for fastening researchers.

Abstract: Nowadays, a growing amount of devices are applied on the car, such as systems for navigation, audio, phones, and driving assistance systems. Car interior function systems will get more and more complicated in feature, which require more attention and increase more work load [1]. This paper aims to describe how to design switches of vehicle operation and control system for enhancing the performance of drivers. Therefore, we conducted an interview of Chinese drivers about the problems with their car to explore the advantages and defects of the current interior design. In the paper some cases were analyzed by applied semiotics theory, to discover how to make the manipulation in in-vehicle easy to understand and use for users. To design easy to-use interface, this essay identifies key principle of designing car switches on the Basis of Semiotics, their features, and problems. In the content, we aim to appeal construct design criterion that could be used to direct later car switches systems.