Key Engineering Materials Vol. 522

Abstract: This paper presents a two-dimensional movement and the one-dimensional rotating 3 DOF robot that can be used to pick up, delivery and place riveting column, thin axis (referred to as riveting column) and other parts, forming the assembly systems of riveting of sheet metal. In addition to the robot, the system also has moving table, clamp, a number of riveting column station and spin riveter etc. Moving table is equipped with the clamp, it can move in the X and Y directions, respectively. The clamp that fixed the sheet metal work-piece can move in Z-direction, which make it easy for assembling the riveting axis into the riveting holes on the work-piece. Robot can move along the Y axis and swing around the Z axis, make the nozzle that is in the end of manipulator move between riveting column stations and spin riveter, which pick up and place the riveting column. A number of riveting column station is used for store riveting column and sorting them. Spin riveter rotates while moving along the Z axis at the same time, by pressure and rotational force it completes the column riveting on sheet metal parts.

Abstract: In the current monitoring system, for the monitoring sites (such as storage, home, radioactive places and other harmful places), no dead ends and comprehensive monitoring is completed by installing a large number of fixed cameras and hiring many security persons to achieve, a lot of cameras installed are complicated; expensive and wasting a lot of manpower and material resources. Meanwhile, the fixed camera monitoring is just rigid; no early warning functions and requiring the security persons to be on duty all the time. At the same time, the records of on-site monitoring need to be large capacity storage medium. Therefore, to solve the problems of above in practical, we design an intelligent network monitoring system which is a set of non-dead mobile monitoring; automatic warning; automatic voice alerting; automatic storage of suspicious scene. By fixing the cameras; wireless routers; GPRS module; voice module and power management modules, with the Altera DE2 board to build a wheeled robot. The wheeled robot realizes the real-time monitoring of unmanned sites and solves the issues of complex installing and adverse monitoring to a large extent.

Abstract: The planar 3-DOF parallel mechanism was developed as a part of the pushing device for the wood sawing. Using closed vector polygon method to make positive movement analysis of the mechanism, establish the positive solution mathematical model. It provided the theory bases for the error analysis and control algorithm of the planar 3-DOF parallel mechanism.

Abstract: In order to improve dynamic characteristics of a machining center column, this paper proposes a structural optimization method based on finite element method (FEM) and response surface method (RSM). In order to reduce number of design variables, the finite element analysis samples in design space are selected by using the central composite design (CCD) experiment method. On the basis of FEM results at these experiment samples, quadratic polynomials are employed to establish response surface model, which reflects the relationship between the response (mean frequency of the first four orders) and the design variables (the column structural sizes). The goal of getting maximum mean frequency is reached by using NLPQL algorithm in iSIGHT. Through the optimization, the mean frequency is increased by 8.12%.

Abstract: Aiming at these problems of complicated analysis, high repeated rate and resource sharing in the process of the NC machine tools design and performance analysis, a development platform is built to integrate the structure design, performance analysis, optimization of spindle and resource sharing. The platform includes digital design, 3D entity modeling and virtual assembly, finite element analysis and optimization, and dynamic simulation module. Each module can normally operate and exchange data by means of coordinating the interface between modules. The experiment shows that the developed system could effectively improve the efficiency of design and analysis of spindle, and could provide reference for the optimization design and the actual production manufacturing.

Abstract: In this paper, a application of signal identification by using fuzzy cluster is studied Based on the one order T-S model, an algorithm for online establishment the nonlinear model between the servo current and cutting force is presented by fuzzy likelihood function to derive fuzzy cluster. Finally, the experimental study has been given. The result showed that it can be regarded as a good dynamic identification algorithm for intelligent control of NC processing.

Abstract: The evaluation algorithm of planar straightness error is discussed. A new kind of method that named as Dichotomy Searching Algorithm (DSA) is presented to implement the minimum zone tolerance for evaluating planar straightness errors. The algorithm meets the principle of the minimum zone tolerance. The principle of the algorithm is that two special provision points are constructed based on the starting endpoint and end endpoint respectively firstly, then the four presume centerlines can be established by connecting the preset two special provision points of the starting endpoint to the preset two special provision points of the end endpoint in turn, after that, calculate the distances between all the measured points and the supposed centerlines. The minimum zone straightness error is obtained by means of compare, judgment and set the new special provision points repeatedly. This algorithm is substantiated with typical examples and the results show that the algorithm can be used to achieve precise computation of planar straightness errors.

Abstract: This paper describes a distributed control system, which is based on PIC microcomputers. The hardware of this system included industrial personal computer, RS232-RS485 converter, control circuit, motor driver and so on. The PIC microcomputers on control circuits are used as basic control chips. The software of system is developed by Visual C++, communicates through the RS485 bus. The human-machine interface is developed, which is intuitive and friendly. Test result shows that the control system is effective and reliable.

Abstract: The development of altitude and remote control for aircraft requires larger rudder piece pitch angle, and Electric actuator needs to withstand larger bending moment as the attitude control executive mechanism. Traditional bending moment and torsional moment of Electric actuator rely on output shaft bearing which are difficult to meet the requirement of resisting large moment. Based on a particular type of Electric actuator system, this paper analyzes its moment resisting capacity, proposes an idea of seperating bearing objects of bending and torsional moment for aircraft, and designs an innovative actuator structure. Moment test experiments show that moment resisting capacity of the new Electric actuator is enhanced to 150% more than orginal one.

Abstract: During the debugging of electric actuator system and aircraft pose control, the electric zero position of electric actuators need complicated adjust because of the existence of machining error in machine after electric actuator system is restart. This paper proposes a on-line parameter configuration method, develops a status parameter memory system of electric actuator system. The system take XC3S400 as core chip and AT24C02 as memory chip, save the state information about electric zero position regulated parameter, important control parameter, and etc. Through on-line parameter configuration, we can abridge the adjustment step of electric zero position which happens in after the electric actuator system is switch off and restarted, simplify operation difficulty, saving time, and improve quickly responding ability of system.