Applied Mechanics and Materials Vols. 799-800

Abstract: In this study, modified genetic algorithm (MGA) and A* search method (A*) is proposed for optimal motion planning of mobile robots. MGA utilizes the classical search and modified A* to establish a sub-optimal collision-free path as initial solution in simple and complex static environment. The enhancements for the proposed approach are presented in initialization stage and enhanced operators. Five objective functions are used to minimize traveling length, time, smoothness, security and trajectory and to reduce the energy consumption for mobile robots by using Cubic Spline interpolation curve fitting for optimal planned path. The purpose of this study is to evaluate the proposed approach performance by taking into consideration the effect of changing the number of iteration (it) and the size of population (pop) on its performance index. The simulation results show the effectiveness of proposed approach in governing the robot’s movements successfully from start to goal point after avoiding all obstacles its way in all tested environment. In addition, the results indicate that the proposed approach can find the optimal solution efficiently in a single run. This approach has been carried out by GUI using a popular engineering programming language, MATLAB.

Abstract: The work presented a research method of using the external magnetic field to do a numerical simulation of micro bionic fish. The fishtail skeleton was made of alloy sheet and the fish tissue was stuck on the alloy sheet with giant magnetostrictive material (GMM). Then the mechanical model of bionic fish was established. By controlling the swaying of fishtail through external magnetic frequency adjustment, it is possible to make the fish move about just like a natural fish. The statistics show that the average driving force when the bionic fish is switched on largely depends on the material parameter, blood viscosity and external magnetic frequency. The average driving force will increase with the growing elasticity modulus (EM) of fishtail material and blood viscosity. The bionic fish can get a quite large driving force particularly when the external magnetic frequency is getting close to the natural frequency of the system. Thus, these findings can serve as a major train of thought and gist for the design and control of micro bionic fish in vessel.

Abstract: The actual miniaturization trend, present in several industrial sectors, requires high performance capabilities in micromanipulation and assembly. A complete automation of these operations, by means of robots, could result in a significant cost cut in the final product. In this work we present the mechatronic design and optimization of a 3 d.o.f. Delta type PKM for micromanipulation. Starting from a reference task (pick and place with high stroke rate) the optimal links length has been determined by considering several kinematic performance indexes; afterwards the actual link sizing has been performed considering dynamic loading, also taking into account the effect of the links flexibility on end effector trajectory. A direct drive actuation has been chosen, where the motor sizing has been performed to satisfy several criteria: maximum and r.m.s. torque and maximum speed. The motor selection has been speeded up querying a database built by collecting data from the catalogues of several producer. Furthermore robot joints have been carefully designed in order to reduce backlash and friction.

Abstract: In this work we have extended a basic linear model of the Electromechanical Throttle Valve to a nonlinear friction model, which captures the most important friction phenomenon of interest for fault detection. In our examination we have implemented the Tustin’s friction model. This nonlinear friction model has only 4 parameters but describes the friction phenomenon of the Stribeck effect also it includes both the Stick and Slip regimes. To the validation of the actuator model and examination of the friction models we have performed experiments using the experimental setup of NI LabVIEW CompactRIO. The friction phenomenon as hysteresis, stick-slip and Stribeck effects, are an interest for fault detection of the Actuator Valve. The experimental results have shown, that Tustin’s model provides a good approach for modeling of the friction behaviour of the Electromechanical Throttle Valve.

Abstract: In this paper, the possibility to build a low cost hovercraft platform with easily accessible materials and able to perform autonomous ground mapping is discussed. To do so, platform design is presented with proportional motors and construction module. The computing system is integrated to manage the platform displacement. Algorithms are used to counteract every constraint existing in this kind of vehicle such as low ground interaction and motors feedback, based on previous research on hovercraft stabilization. The mapping system which includes a camera and a laser is discussed in detail, and final mapping and exploration is computed with inspiration from mapping research.

Abstract: In this paper, we present a new knowledge push technology for complex mechatronic products design based on ontology and variable precision rough set (VPRS). Ontology can explicitly represent knowledge semantics and let designers exchange knowledge about design and the product development process; while using the knowledge reduction method based on the VPRS method, the design knowledge repository is simplified and design rules also be distilled from the reduct design knowledge repository. On the basis of the above approach, multiple designers can efficiently share design knowledge and can obtain appropriate design knowledge during all design processes. Finally, a case is employed to validate the proposed method of this paper.

Abstract: Effect of the compressible flow characteristics inside a high-speed electromagnetic valve on the operation of the valve is investigated using a numerical simulation. The numerical simulation solves Navier-Stokes equations and heat transfer equations by coupling, and the compressible flow phenomena inside the valves are studied focusing on the shock structures. . Fluid-structure interaction is considered using freely moving grid deformations. The flow patterns of subsonic acceleration, choked flow, supersonic expansion, and a strong curved shock were observed inside the valve during on/off operations. The subsonic flow acceleration affected the operation characteristics of the valve.

Abstract: Aiming to get better real time performance and effect of detection in dynamic scene of intelligent video surveillance system, non-parametric kernel density estimation (KDE) is used to model the background. And to solve the foreground detection is not precise enough, background subtraction method is fused to detect the foreground. And some modified work is done to suppress shadow and noise. Experiments show that the method proposed can get better real time performance and low noise detect result in intelligent video surveillance system.

Abstract: In this paper, a linear quadratic Gaussian controller is proposed to achieve the robust temperature stability of the fuser system against measurement noise and system disturbance. The proposed controller is fitted to replace the PI controller and relative mathematical derivation is described. The system is implemented using MATLAB and SIMULINK with adding the noise and disturbance. Improvement of performance is verified by comparison with conventional PI controller results on several key factors of the fuser system.

Abstract: With the rapid development of industrialization, the intelligent control has increasingly replaced the traditional process control in PLC in recent years, in which some intelligent control strategy has been applied to industrial control cases, such as genetic algorithm, fuzzy control, expert control and neural network and so on. However, it is not sufficient to achieve the desired control effect if only an intelligent control method is applied in the intelligent control. Therefore, integrated intelligent control of various control strategies is bound to be a focus in the embedded intelligent control. At the same time, with growing power of the PLC processing, it is possible for complex algorithms to be used in the embedded application, which has great significance in the development of industrialization as well as intelligent control.