Applied Mechanics and Materials Vols. 651-653

Abstract: In view of the cooling difficulty in complex injection mold, the difference between conventional cooling channels and Conformal Cooling Channels (CCC) is researched. CCC is superior to conventional cooling channels on cooling effect according to the simulation analysis of plastic flow based on Autodesk Moldflow Insight software. Considered the manufacturing difficulty of CCC, an approach which uses three-dimensional printing and investment casting is put forward in the end.

Abstract: To solve noise and vibration problem and other problems of helical gears, to improve its reliability and safety, this paper uses transmission of helical gear as the research object and makes an analysis of dynamic characteristics of time-varying contact wire and time-varying friction after giving the length of the contact wire, time-varying friction and fast Algorithm for the friction torque. The results of experiment show that the fluctuations of time-varying contact wire is an important cause of tooth surface friction and tooth surface friction torque fluctuations. Time-varying contact wire length, tooth surface friction and friction torque fluctuations are smallest at twenty centigrade degrees, which provide a theoretical basis for the parameter design of gears and engineering optimization.

Abstract: The choice of the element type of finite element is different and the division of elaborate degree of meshing is different, so the results of analysis on different modals are different. Combined with the use of ANSYS, specific practice analysis of modals, experimental result, various methods of modal analysis, this article states about the specific methods of modals analysis on carburetor.

Abstract: By using the finite element software Dynaform, the process of tee pipe hydroforming is obtained with the analysis of forming force, the extrusion speed, die radius, friction conditions and the initial length of tube rounds, which are key process parameters on the influence of tee pipe. Obtained by analyzing the tee pipe hydroforming law, to the actual production of tee pipe hydroforming process design provides the reference data and related guidance.

Abstract: With the demands of machine tool accuracy and stability for manufacturing are getting higher and higher, the effect of cooling oil is increasingly evident. And it is proved that cooling oil temperature is an important factor for machine cutting precision and stability. Continuous cutting test was carried on and values of over pin dial (M) were measured. The results show that it has large effect of cooling oil temperature on the stability of M-value. Subsequently, test of machine capability index (CMK) was carried on. And it was verified that the CMK of gear shaping machine is larger than 1.67. And the results show that the fluctuation of M values is the smallest when cooling oil temperature is 33°C. Lowest time costing for adjusting the processing system, highest cutting accuracy, and smallest value of stable amplitude for Gear Shaping Machine could be obtained at this condition.

Abstract: Application of Adaptive Neuro-Fuzzy Inference System (ANFIS) in engine fault prediction is introduced in this paper. For insuring the engine safety and reliability, the fault of engine must be predicted, and the fault can be terminated in time. So, the fault prediction theory and the method of ANFIS are studied. The fault prediction sets, the structure and parameters for ANFIS are given in the course of fault prediction. It has made very pleased result through experiment of certain type engine fault prediction, and it is important to engine maintenance. The application of ANFIS has a good reference to engine fault prediction researching.

Abstract: This paper selects two kinds of different avoiding valve pits of piston as the processing object, establish manufacturing process and complete the simulation of NC machining to generate NC code for machining avoiding valve pits in the Mastercam software, try to machine avoiding valve pits with two kinds of surface programming method in the Mastercam software, discuss and analysis the effect in programming and NC machining of avoiding valve pits in two kinds of different surface finishing method , to choose an appropriate kind of processing method for avoiding valve pits of piston.

Abstract: In view of the high order, nonlinear characteristics of target trajectory, control strategy is proposed for a kind of RBF neural network and polynomial interpolation combining. According to the specific requirements of trajectory planning, the manipulator in joint space variables are expressed as one or two order derivative function by polynomial interpolation algorithm, then the RBF neural network is used for tracking the target trajectory. Finally, through MATLAB simulation, the accuracy of this method is verified.

Abstract: The paper analyzes the effect of airfoil thickness, camber and blade pitch angle on the performance of the three-bladed Darrieus wind turbines. The research results show that the increase of airfoil thickness, camber and pitch angle of blade, can improve power coefficient when the wind turbine tip speed ratio between zero and four. The increase of thickness and camber of the airfoil leads to running tip speed ratio range of wind turbine get narrowed, and reduces the power coefficient when wind turbine runs in high tip speed ratio range. When the pitch angle of blade is 1˚, power coefficient reaches the maximum value. Negative pitch angle has a bad impact on power coefficient and even creates negative power coefficients.

Abstract: Obtaining the flight attitude of high accuracy, high reliability is a prerequisite for achieving the autonomous flight of the multi-rotor UAV. MEMS gyroscope can solve attitude angle individually. The paper adopts Euler angle and quaternion algorithms respectively to calculate attitude angle of the multi-rotor UAV. The flight experiment shows that the quaternion algorithm can guarantee the accuracy and the stability of the attitude angle calculation. The root-mean-square errors of the pinch roll and heading angles which are calculated by the quaternion algorithm are 2.947o, 3.606o and 9.769o, which can meet the demand for the autonomous flight of the multi-rotor UAV.