Key Engineering Materials Vol. 693

Abstract: The traditional fixed pitch error compensation method exists some defects, such as sampling points are not comprehensive and the necessary compensation points are easy to miss. Faced with these problems, this paper presented a new pitch error compensation method based on the open numerical control system. With this method, the traditional measurement points were serried, and more pitch error data were measured. Then calculated the error data with the cubic spline interpolation computation method, and the compensation location and value were obtained according to the accuracy requirement. The pitch error compensation was completed when the data inputted into the open numerical control system with a defined format.

Abstract: The paper introduces a new 3D wax printer, including its technical proposal, integral structure and control system. The raw material of this 3D printer is a mixture which is composed by wax, cyclohexane and alcohol. Raw material is transmitted to nozzle by a transmission device. The raw material which is squeezed out from nozzle deposits into product on the working platform. The paper also introduces the motion control of motor which is the hardcore of control system.

Abstract: This designed system adopts the Embedded Linux operating system to achieve this desired embedded characteristic and further it proposes annular buffer technique to provide continuous data acquisition with no sampled data loss. Through monitoring wheel hubs’ operation, which works to evaluate the performance of cars, the system is demonstrated to be able to provide reliable and continuous data for equipment.

Abstract: The requirements of CNC machine tools for the feed servo system could generally be summarized as high precision, well stability, fast response, wide range of speed regulation, high torque at low speed and so on. The PID controller of feed servo-system based on intelligent fuzzy control was presented based on traditional PID controller. The main feature of this arithmetic was to change parameters in different degrees according to time-varying working conditions, specially this arithmetic could change its domain intelligently according to different conditions and cooperated with a stable controller in case of system crash so that adaptivity and reliability of the feed servo-system were improved, also this feature made application field of the feed servo-system wider.

Abstract: Based on the analysis of the advantages and limits of the traditional fault tree and Bayesian network in fault diagnosis, the method that building the fault Bayesian network based on fault tree is proposed in this paper. The paper introduces the correspondences between elements of the fault tree and the fault Bayesian network, also describes the inference process of the junction tree algorithm in the fault Bayesian network. Then with the foundation brake rigging system of CRH380AL EMU as an example, we build up the fault tree, complete its transmission to the fault Bayesian network, proving the superiority of the fault Bayesian tree in fault analysis of the complex system at last.

Abstract: The dynamic problem is defined as the way the motion of the robot arises due to the torques and forces applied at the joint by the actuators. The motion undergone by robotic mechanical system should be as, a rule, as smooth as possible, abrupt changes in position, velocity, and acceleration should be avoided. Indeed, abrupt motions require unlimited amounts of power to be implemented, which the motors cannot supply because of their physical limitations. In this paper an analytical solution for the dynamics of 3 DOF gantry robot presented to achieve those goals, so our aims is to model the dynamics of gantry Robot for simple pick and place application. Equations of motion are derived using the Lagrange equations of the second order, the dynamical model of robot was developed, and the gantry robot system was modeled in SOLIDWORKS software environment and it was simulated using ADAMS software. The manipulator is composed by four basic modules defined as module X, module Y, module Z and terminal arm, where is connected the end-effector.

Abstract: Regarding the problem for the existing CNC machining tube tip with the old car exists thread groove, on the basis of the mechanism analysis and experimental study, the detection of inherent inter-spindle screw thread cutting tracks with old spiral phase angle technology is herein proposed. Detected by the advanced hardware and software data processing technology, and strive to achieve the alignment tool for automatic restoration of the old spiral grooves machined technological breakthroughs, innovation and invention of the NC system turning tool with new features slot. Pipe thread repair machining accuracy and efficiency is significantly improved, which savelots of manpower and material resources.

Abstract: According to the characteristics of the electro-hydraulic position servo system of asymmetric hydraulic cylinder controlled by symmetric valve and its performance requirements, the PID controller based on disturbance observer is introduced. The improved controller can observe the equivalent disturbances and introduce the equivalent compensation to the control system, so it can achieve suppression of disturbance. In the MATLAB Simulink environment, the simulation results show that the controller has the very good quick response, the stronger robustness and the higher tracking precision.

Abstract: An apparatus is developed in this paper, which surveys the motion law of the CAM follower. The apparatus is comprised of the frame body, motors, transmission system, execution system, control system and data acquisition system. The displacement curve, speed curve and acceleration curve of CAM are drawn by analyzing the signal from the dial indicators. This apparatus can provide technical data for the mechanical principle course as well as scientific research work.

Abstract: Over the last few decades, the range of engineering materials encountered in machine shops has increased greatly, as has the variety of cutting tools that are capable of machining these materials. The tasks of tool selection and cutting parameter recommendation for performing the operations are complex and require development of intelligent system. A cutting tool database system model is proposed in this paper. And base on the model, this paper presents a cutting tool database system for selection of cutting tools and conditions of turning operations. The model incorporates intelligent tool selection technology, optimization methods of tool selection and cutting parameter. An application example of the system was performed to demonstrate the practicability and validity of the prototype system.