Applied Mechanics and Materials Vol. 680

Abstract: In this paper the rigid-flexible coupling dynamic characteristics for an existing constant temperature oscillator based on ADAMS has been investigated. The unbalance load caused by the rotation of the eccentric mass is carefully calculated. In view of this phenomenon, a new centroid adjustable balancing head is put forward, and the scheme is verified by ADAMS.

Abstract: A novel technique for determining the energy-optimal base position of common Industrial Robot (IR) is presented. At first, an energy-focused IR model is developed by means of the Modelica/Dymola simulation environment. Then, for a given IR task, a standard but efficient optimization technique is employed, which allows to determine the robot base position corresponding to the minimum energy consumption. A set of graphical maps is finally provided, which allows a rapid estimation of the energy demand along with the time required for the task completion.

Abstract: The paper presents an analysis of displacements and the load distribution between elements in the planetary roller screw for assumed computational model. Based on the analysis of stresses and threads deformations the load distribution on threads for the case of consistent and opposite load of the screw and nut is obtained. By applying finite element analysis the stiffness of the contact regions on threads was estimated for various dimensions of the screw, roller and nut.

Abstract: In this paper one tried to realize an automated system based on PIC16F84 microcontroller and several sensors, a punching automatic line, served by a portal robot type that can be modified and adapted to a variety of technology processes, which requires series production.

Abstract: This paper studied the fuzzy PID method on controlling permanent magnet synchronous motor servo system. The servo control system consists of the S3C2410 and drive circuit, etc. A fuzzy PID controller is designed by combined fuzzy control with conventional PID control, Fuzzy inference rule of PID parameters is designed according to nonlinear and uncertainty of the PMSM servo system, which would result in changes of characteristic parameters of object or structure. Simulation results indicate that the fuzzy PID controller is superior to the conventional PID controller in dynamic stability performance.

Abstract: To improve the performances of air-powered engine (APE) used on the pneumatic and its hybrid vehicles, the electronic control system of APE was developed based on the single-chip microcontroller. The design process of hardware and software subsystem of the electronic control system was put forward according to the characteristics of APE and the resources of XC886 chip. The evaluation test was conducted to validate the electronic control system of APE. The experimental results show the control system can function well under any given conditions.

Abstract: According to the working condition and characters of pneumatic servo system, the mathematic model of switching valve and executing cylinder controlled by pulse width modulation were built. The mathematic model was made use of in the flow regulator used on gas generator and the simulation model was built with Simulink in Matlab. According to the simulation model, the dynamic characteristic was analyzed.

Abstract: Through the investigation of some problems of subway, that is, abnormal wheel tread wear and excessive brake shoe abrasion, caused by applying irrational electro-pneumatic brake force distribution strategies in the quotidian operation subway lines, a braking system simulation platform based on AMESim is established in order to point out the pros and cons of various distribution strategies, such as diverse converting points of electric and pneumatic braking, assorted pneumatic brake force distribution methods; the indexes include brake shoe pressure and imposed time of pneumatic braking; service brake and emergency brake are regarded.

Abstract: The method of numerical simulation of the centrifugal separator is presented. The separator carries out alternative way of mechanical cleaning petroleum products from inclusions of water and sludge. Questions of the boundary conditions, creation of a settlement mesh and a method of calculation of two-phase liquid are considered.

Abstract: Finite element model for the system of foundation and its surrounding homogeneous soil is established based on software ABAQUS to analyze the uplift behavior of excavated foundation of transmission lines. The influence of soil properties and embedment ratio were analyzed. Deep mode occurs when embedment ratio is more than 4. As for shallow mode, the shearing method based on cylinder sliding surface was used to estimate uplift capacity. The expression of nominal uplift coefficient of earth pressure Ku in the formula was determined via back-calculation and fitting, which is the function of embedment ratio, friction angle and cohesion simultaneously. The errors of uplift capacity from fitting formula and numerical analysis are all within 15%.