Applied Mechanics and Materials Vols. 246-247

Abstract: To realize braking pressure fine regulation, the characteristics of hydraulic system should be well known, and there be a proper control method. By testing pressurization of braking circuit, the relationship between wheel cylinder pressure and current of the inlet valve was summarized, and the right rule of inlet valve current changing was found according to demands of pressurization. Finally, real car tests were carried out, and results prove the feasibility of this method. System can realize pressure fine regulation by this method, and get the goal pressure of control requirement.

Abstract: With the development of production automation and science and technology level, the intelligent level of the car is continuously improved. For intelligent car, with STC89S52 single chip microcomputer as its core of control, the direction and speed of it is controlled by the collection and processing of the signals from various kinds of transducers in the forward path. Therefore, the functions of automatic identification of black guide line applied to rapid and steady running status of the car and the obstacle color discrimination applied to direction selection during the course of running and other relevant functions can be realized. In this system, a DC motor is used for the forward and steering movement of the car, a LCD1602 is used for the display of its travel time, and a dual power supply by which system stability can be enhanced is used for the motor and control system respectively. Besides, the system control software is designed to be a combination of software and hardware, through which the anticipated functions of the car is ultimately realized.

Abstract: At present, no intellectual games beneficial to both human left and right brain development simultaneously can be observed within China, oriented to which a design of desktop balance reflection ball system is realized in this thesis. Several main contents can be noticed. Firstly, with the participants' manual push torsion as the power source the direction of the handle control and the one of the game table swing movement of the system are made reverse on the principle that the cam swing exerted by the push and pull movement of the link rod is driven by the swing of the tee iron; thus, the control direction of the ball is made reverse with the one of human thinking inertia. Secondly, the game platform is made into a structure freely adjustable labyrinth pattern, and for convenience of operators of different heights the support unit is equipped with a height-adjustable triangle bracket. Thirdly, several softwares such as AUTOCAD is applied to this system design in the establishment of the 3D stereo model, through which the efficiency and quantity of the design are improved and the development circle of the system prototype is thus shortened.

Abstract: This paper puts forward an inverter design method based on TMS320F2812A. For inverter part we adopt double closed loops control method, on the basis of the analysis of the inverter designed the controller parameters, and realized the digital control algorithm through TMS320F2812A. Introduce the design method of the hardware system, and give the flow chart of the software control. Finally simulate the double closed loops algorithm though MATLAB, and test whether the control algorithm is feasible.

Abstract: This thesis imitates the practical working environment of certain special bush and accomplishes the design of parts wear test device. By the development of PLC operating system, it combines the tester and principal computer and achieves the automatic control of experimental procedures and the supervisory control of experimental tasks, establishing relatively complete data acquisition channel and accurately analyzes fatigue property of parts by the fitting liner wear curve of the least square method. This promotes the development of special the experiment of fatigue property of parts.

Abstract: A constellation design method is presented which applies to formation flying configuration of highly elliptical orbit satellites. The design method uses approximately relative kinematics equation in determining initial satellite orbits elements of the constellation with an envisaged formation flying configuration and precisely relative kinematics equation in predicting orbits, and then analyzes the envisaged configuration stability so as to judge whether or not the configuration can be well maintained only by natural disturbing forces, without the need to add any control. The approximately relative kinematics equation is derived from the precisely relative kinematics equation on the basis of two assumptions. The precisely relative kinematics equation can take into account all kinds of disturbing forces in order to analyze the constellation configuration stability in as real dynamics circumstances as possible. In the presented work, the configuration design example of a constellation composed of five surrounding satellites and an objective satellite, all with high eccentricities, are analyzed by simulations. It is seen that the constellation design method effectively solves formation flying configuration for highly elliptical orbit satellites.

Abstract: By carrying on the stress and transform analysis of the box of a kind of main reducer which was self— designed and manufactured for vehicles, by ROMAX modeling get accurate bearing load and conducting ANSYS finite element analysis. it is shown that structure design of the main reducer box is very important for the intension capability of the box, and for the transmission functions of the main reducer. The hidden trouble of the main reducer transmission due to the designers was solved, which couldn’t estimate the transform of main reducer box by traditional design method, and provided the necessary basis for further optimizing and ameliorating the whole transfer case system. By using the UG software we constructed a complicated model of the box, and carried on a series of accurate intension and fatigued analyses for the model by using ANSYS software.

Abstract: The automatic up-down material manipulator wrist requirements compact structure, rational layout. The typical wrist structure has a variety of, this design wrist structure for step motor drives a turbine worm movement of the structure, main function is to drive the PAWS, make its can accurately to grab parts and placed parts. Operation mode for step motor drive worm and worm wheel rotation, and then drive the turn of the wrist. Through the design of the wheel of worm gear and worm gear design, step motor selection, etc, and then, a 3 d design, and gives a picture.

Abstract: Design and analysis of multi-spindle transmission device helps to improve design quality and efficiency of aggregated machine tools and other automatic mechanical devices. This paper analyzed principles and structures of two multi-spindle transmission mechanisms adopted extensively in mechanical area. A three-dimensional prototype of the multi-spindle drilling device designed for machining six holes simultaneously was built with Pro/Engineer software. The device adopted multi-spindle reciprocating transmission mechanism. The application of the software involved creating simplified model used for motion analysis, performing kinematic analysis of the mechanism, establishing measures of main parameters and executing optimal design of key parts.

Abstract: ASTM A36 carbon steel is the most commonly available of the hot-rolled steels. This specification covers carbon steel shapes, plates, and bars of structural quality for use in riveted, bolted, or welded construction of bridges and buildings, and for general structural purposes. The research was to study the in effected of gas tungsten arc welding parameters which effects the hardness and physical characteristics of welding for carbon steel ASTM A36. The specimen was carbon steel sheet metal 6 mm thick. The 2³ factors experiment was used polarity direct current electrode negative (DCEN) and alternating current (AC), welding current at 90 and100 amperes with tungsten electrode angles at 30 and 60degree. The weld sample was test by hardness and penetration. The result showed that polarity, welding current and tungsten electrode angle had on interaction on hardness and penetration at 95% confidence (p-value < 0.05).The factors made maximum hardness was polarity AC, welding current 100 amp. and tungsten angle 60๐of 803.16 HV. The factors made maximum penetration was polarity DCEN, welding current 100 amp. and tungsten angle 60๐ of 2.71mm. The research data can be used to determine the appropriate gas tungsten arc welding process of carbon steel weld.