Advanced Materials Research Vols. 605-607

Abstract: The crossbeam is one of the main supporting parts of large gantry CNC machines. The deformation of the crossbeam under loads at work has great impact on integrated machining errors of machines. However, the crossbeam assembly’s structure and the corresponding loads are so complex that it’s difficult to get them through experiences and analytic methods. In this paper, the FE statics analysis method is used to simulate and analysis of the crossbeam under six main working conditions, obtaining deformation and stress distribution of the crossbeam under each conditions. The results show that when the slippery saddle is at the middle of the crossbeam and the ram extends to 100% length (the distance between the end of ram and the bottom of slippery saddle is 1.29 m), the total deformation of the crossbeam assembly is 6.4914 × 10^-5 m, the maximum deformation is up to 3.4872 × 10^-5 m, and the maximum stress is 1.1882 × 10⁷Pa appearing at the hole of the drive shaft. The design of the crossbeam can meet the work requirements well. And analysis results present a basis for further optimization analysis and structural improvements of the crossbeam.

Abstract: A machine vision on-line detection system for automobile frame side fail mounting holes is proposed in this article to solve the backward and low-efficiency problems for detection methods of large-size automobile frame side fail mounting holes. Many images captured by CDD camera are processed and analyzed by virtue of algorithms such as image stitching, threshold segmentation, edge detection, feature extraction, etc.. The developed detection system prototype has very high detection accuracy.

Abstract: A novel ball-end mill manufacturing algorithm of 5-Axis CNC Machining grinder and the simulation test of the algorithm based on a CAD system are presented in this paper. In order to obtain an accurate algorithm of a ball end mill machining, a mathematical model is needed so that the shape of the mill can be parameterized. Therefore, the mathematical model can be adjusted based on that model. Each of the processing parts has its own position in the local coordinates system. Then, with the coordinates determined by the mathematical model, the partial coordinate and the relative movement between the grinding wheel and the barstock in the local coordinates system can be calculated. So that the 5-Axis manufacturing coordinate can be confirmed by the partial coordinate and the structural parameter. If we input these data and make the 3D-CAD simulation before the machinery manufacture, the algorithm can be tested effectively.

Abstract: The application of PLC 、Stepper motor driver and Encoder are introduced in stepper motor closed-loop control system. The Principle diagram is analyzed, the Control System flow chart and Software program are designed. Through in-situ operation, the system has been proved well reliability、 stability and simplicity , achieved high accuracy and low cost requirements。

Abstract: The modal analysis of machine tool bed was done by means of finite element method. Find out its characteristics of vibration modal. Then structure improvements on arrangement of tool bed reinforcing plates were done. After the structure improvements the natural frequencies of the tool bed were improved.

Abstract: With the development of robot technology, massage robot has attracted fully attention, and the study about robot arm has been a growing interest in the area of massage robot. This article has put forward a new massage robot arm, which uses the chain as the main transfer mode by the requirements of the overall design massage of the robot arm. The design of big arm, shoulder joint, forearm, elbow joint and wrist are introduced. Based on the design requirements, we made some improvements with sprockets, ensuring transmission conditions and meeting the massage requirements. And finite element analysis for the designed arm, results show that the structure design can meet the requirements.

Abstract: The production of IC equipments requires tight control of temperature uniformity within the substrates during the vacuum deposition process chamber. Though traditional approaches such as PID control methods result in substantial improvements, but they fail in meeting the stringent requirement of less than 1°C variation to guarantee the long-term stability of the temperature. To this end, this paper describes the application of information fusion closed-loop control system.A heater structure was designed and the heating wire was divided into 3 sections. Then a multi-loop temperature coordinated control system model has been developed and the temperature heating process has been divided into five intervals. In order to achieve the desired temperature uniformity of 1°C, information fusion technology was used to predict the parameters of PID controller. Through experiments, the coordinated control system model can attaining the desired uniformity levels.

Abstract: In order to obtain accurate dynamics parameters, a two-step method for robot dynamics parameters calibration is presented. In the first step a multidimensional matrix is constituted through transforming the configurations of robot manipulators and the product of quality and centroid coordinate about links is solved by using the least square method. In the second step decoupling dynamic equation of robot is deduced based on Newton-Euler algorithm, and through planning specific joint movement, the inertia tensor and centroid coordinate of robot links are calibrated making use of the pseudo inverse method. By the above two steps, the entire calibration of robot dynamic parameters is achieved. The correctness and feasibility of the presented calibration method is manifested by simulations and experiments.

Abstract: Automatic trajectory generation for spray painting is highly desirable for today’s automotive manufacturing. Generating paint gun trajectories for complex curved surfaces to satisfy paint thickness requirements is still highly challenging due to the complex geometry of surfaces. In this paper, based on existing of method which complex surfaces are divided into patches to satisfy the constraints, two path optimization algorithms for path pattern have been developed. Two algorithms are developed to optimize the spiral path and zigzag path on a patch by modifying the planning direction of paint gun path. The results of simulations have shown that the two path planning algorithms achieve satisfactory performance.

Abstract: A novel 3SPS/UP spatial 3-DOF parallel mechanism is studied. The studied mechanism is composed of a moving platform connected to a fixed platform by means of four actuated limbs. The three of the four limbs are SPS serial manipulators and the other one is UP serial manipulator. Each SPS limb consists of a spherical pair S connecting to the fixed platform, a prismatic pair P, and another spherical pair S connecting to the moving platform. The UP limb consists of eight Hoke joints U and a prismatic pair P. One side of the UP limb is connected to the fixed platform by Hoke joints U and another side is fixed to the moving platform. Moving character of this mechanism are analyzed by using the theory of screws. The moving platform of this mechanism have three translational DOFs