Applied Mechanics and Materials Vols. 220-223

Abstract: After discussing the charging and discharging characteristics of valve regulated lead acid(VRLA) battery, we described the working principle of UC3906. Then designed the controller of 12V battery charge circuit, 12V battery discharge protection circuit and lamp detection control circuit. This controller achieved automatic switch of lighting system, it could efficiently charge the battery and avoid over-charge or over-discharge. The result showed that this controller extend the life of the battery.

Abstract: For diving control of autonomous underwater vehicle (AUV), a sliding-mode PID control with backstepping is proposed. First, an equivalent model of AUV is developed. Then, the sliding mode control with an PID sliding surface is proposed for the trajectory tracking control of AUV. Moreover, the analysis of stability can be completed by Lyapunov stability theory. Finally, To validate the proposed control scheme, the simulation results are illustrated in this paper. Simulation results show that, the tracking precision and the robustness of the system are improved under the proposed control method.

Abstract: A dynamic sliding-mode control (DSMC) with backstepping is proposed for diving control of autonomous underwater vehicle (AUV), where surge force and stern plane are only available for vehicle's 3DOF diving motion. First, an equivalent model of AUV is developed. Then, the DSMC with an asymptotical sliding surface is proposed for the trajectory tracking control of AUV. Moreover, the analysis of stability can be completed by Lyapunov stability theory. Finally, To demonstrate the effectiveness of the proposed method, the simulation results are illustrated in this paper. simulation results show that, the tracking precision and the robustness of the system are improved under the proposed control method.

Abstract: This paper presents a target recognition method based on SIFT features matching and image ROI technology for vision system of assembly robots. In order to accelerate target recognition method, color histogram is used to detect the region of interest in images, then SIFT algorithm is employed in the ROI to extract the features. Thereby, the image Gaussian pyramid structure is simplified and the computation cost is reduced significantly. The experimental results show that this method can quickly recognize the objects without the loss of robustness and accuracy, and can provide necessary visual feedback information for assembly robots in approaching and operating task.

Abstract: In order to improve the operating efficiency of the seeder, design an automatic control system, this study adopts programmable controller PLC, introduced the composition and connection way of hardware, part program of the ladder diagram, and a variety of modes of operation technology, fully meet the requirement of automatic control, experimental studies have shown that the qualified rate of seeding is more than 90%, up to 500 discs per hour.

Abstract: RoboCup is an international joint project to promote artificial intelligence, robotics and related fields. This paper presents a program that can draw and edit a drawing about soccer Robots and field scenarios. The program can load and save an image file, and draw 2D primitives in a painting area. These primitives can be set with different heights and tested by their compatibility with a new primitive. It also can undo/redo a drawing operation. There is a grid function to simplify the positioning of primitives. All the shapes in the drawing can be aligned appropriately. The result shows that the program can meet the basic requirement.

Abstract: This paper presents a new wireless electricity acquisition system based on General Packet Radio Service (GPRS) technology which is designed according to the requirements of the seawave power for real-time and reliability of data transmission. The direct connection between GPRS network and Internet is effectively used in this system to establish the wireless communication channel, so as to realize the real-time and reliable collection and transmission of the power parameters of the seawave power system. The communication principles and characteristics of the GPRS technology are systematically introduced in this paper. The hardware and software composition, communication model and implementation of the wireless power acquisition system are described particularly. Extensive experiments show that the system has advantages of simple structure, high transfer rate, low running cost and high reliability.

Abstract: Human ability to explore planets (e.g. the moon, Mars) depends on the autonomous mobile performance of planetary exploration robots, so studying on terrain classification is important for it. Vibration-based terrain classification unlike vision classification affected by lighting variations, easily cheated by covering of surface, it analyses the vibration signals from wheel-terrain interaction to classify. Three accelerometers in x, y, z direction and a microphone in z direction were mounted to arm of the left-front wheel. The robot drove on the sand, gravel, grass, clay and asphalt at six speeds, three groups of acceleration signal and one group of sound pressure signal were received. The original signals were dealt using Time Amplitude Domain Analysis. Original data were divided into segments, each segment was a three centimeters distance of driving; eleven features from every segment were normalized. The data from four sensors were merged into a forty-four dimensions feature vector. Ten one against one classifiers of Support Vector Machine (SVM) were used to classify; one against one SVM program from LibSVM was applied to multi-class classification using voting strategy in MATLAB. Facing to the same number of votes, we propose a new algorithm. Experimental results demonstrate the effectiveness of the feature extraction method and the multi-class SVM algorithm.

Abstract: In order to gain the same amplitude、frequency and phase between the output voltage of the inverter and the grid voltage, the phase-locked loop (PLL) technology is widely used in grid-connected photovoltaic (PV) generating system, which is normally used to obtain instantaneous phase information to achieve the grid-connected purpose of PV inverter. The detective accuracy of frequency and phase of the grid voltage is directly affected by the PLL. Two software PLL technologies are compared by using the simulation analysis which is based on the d-q transformation. To provide the basis for the design of grid-connected inverter, the advantages and disadvantages of two software PLL technologies are analyzed under different grid failure conditions, such as one phase voltage dropped, two of three phase voltage (TPV) dropped, grid frequency mutated, and grid voltage offset, etc. Particularly, the appropriate PLL technology can effectively improve the grid-connected ability of PV inverter under the grid voltage offset or unbalance conditions.

Abstract: This paper presents an advanced method with hierarchical architecture for multirobot formation control. The control system consists of fundamental behavior module, supervisor module and velocity tuning module. Formation and obstacle avoidance behaviors are produced by fundamental behavior module, among which the obstacle avoidance behavior is produced by fuzzy logic technique. Then a FNN (Fuzzy Neural Network) is designed to fuse the two fundamental behaviors in supervisor module. The FNN is trained through reinforcement learning. At last, a velocity tuning module is designed to adjust the speed of the robot. Simulation results validate the feasibility of this method．