Key Engineering Materials Vol. 693

Abstract: Aiming at the low accuracy problem of linear model of Valve-controlled motor system in conditions of frequent start-stop and commutation, the nonlinear characteristics of the main components of valve-controlled motor system are analyzed, and non-linear mathematical models and simulation models are established to study the impact on the system of each nonlinear characteristic separately. Hammerstein model consists of a static nonlinear part and dynamic linear part connected in series is adopted, and the non-linear characteristics are introduced to the system. The multi-frequency sinusoidal input signal of test is used as the input of Hammerstein simulation model. And the simulation results are compared with test results and other model output, the results proved that the nonlinear characteristic impacts of the motor valve controlled system really exist, and Hammerstein model can describe nonlinear characteristics of the system accurately.

Abstract: Collision detection is the core of the numerical control system of intelligent manufacturing in the manufacturing process of rapid feeding, positioning and cutting. We need to avoid collision between the cutting tools, machine tools and workpiece. Based on the characteristic of five-axis CNC system, we analyze the advantages and disadvantages of Hierarchical Mesh Segmentation and Octree. At last, we use the collision detection algorithm of cuboid and separation axis to optimize the algorithm of traditional NC machine tool collision detection, which improve the detection efficiency and accuracy.

Abstract: This paper investigates the software error compensation in CNC machining centers On-line inspecting system. Based on Windows 2000 operating system, compensation software is developed. It investigates modeling errors. The software can compensate probe errors, thermal and geometric errors. The software system is tested on MAKINO upright CNC machining centers, and the results verify the effectiveness of the method.

Abstract: The high-speed pulse outputs of PLC can control motion of stepper motor or servo motor. So PLC can complete interpolation function which CNC can do using a kind of simple algorithm. What’s more, the PLC can be developed to be a controller of economical CNC machine tools. Based on the experiment platform of modern robot industrial, the paper introduced how to control the motion of servo system by PLC in detail, and completed the two-dimensional interpolation program through PLC using the direct target tracking as interpolation algorithm. The direct target tracking algorithm could form a series of micro straight line segments approach the desired interpolation trajectory through directly calculating a series of minimum interval points on the interpolation line and connecting these points end to end. Compared to the single pulse interpolation, the direct target tracking algorithm simplified interpolation algorithm and adapted to the PLC program, so it is suitable to economical CNC system. By programming and running in the experimental platform, it can achieve better results using the direct target tracking method as interpolation procedures.

Abstract: Bevel gear is a complicated curved surface parts, the traditional measuring method of bevel gear is by three coordinates measuring instrument for related parameters measurement and there are problems such as reload, high cost and waste of time. In this paper, development of Bevel gear on-machine measurement system based on open CNC system so that the manufacturing and measuring of bevel gear on the same machine tools. This article mainly has studied on structure and function of the system, analyzed the method of pitch deviation and the tooth surface error of the bevel gear and developed bevel gear on-machine measurement system by combining the method of MATLAB with VC++ mixed programming.

Abstract: In order to fulfil the actual request of machining process to the machining database system, according to the characteristics and requirements of machining process, the fuzzy technology and case-based reasoning method were introduced to the design of machining database system. The reasoning process of case-based reasoning method and three main aspects of the fuzzy model were discussed. The match of cases and fuzzy comprehensive evaluation were introduced. The function of high-speed machining database was analyzed and the structure of the database was described. The users can use the database to acquire the overall solutions about high-speed machining.

Abstract: Hybrid electric technology had been introduced into construction machinery from vehicle field. Hybrid electric bulldozer was focused by researchers recently. For constructing a simulation platform of the series tracked hybrid electric bulldozer on whole working condition, a model was built through the secondary development of ADvanced VehIcle SimulatOR (ADVISOR), which could simulate its performance on straight and steering working conditions. In the modeling process, bulldozer’s dynamics model, track walking mechanism model and oil pump model etc., were established and inserting by Matlab/Simulink. The field experiments were performed. The data from experiments and simulation outputs were compared to validate the correct of the model. The results showed that the operating parameters of model were in close proximity to those of experiments, which verifying the established model had significant high accuracy.

Abstract: To change the empty talk phenomenon of the research of a current AC servo system, virtual reality technology is used to develop the virtual simulation system of an AC servo system. This article described the fundamental principle of the sinusoidal pulse width modulation, introduced the functional structure of the virtual system. The fundamental principle of a wave display and the treatment of the key detail problems were solved. In the end, an example of the AC servo system simulation was given. The simulation of the AC servo system can be used as a soft device instead of a real one, and provide a technology platform for the development of a new AC servo system.

Abstract: Motor synchronous control technology has been widely used in lifting device. The effect of Synchronous control technology to improve the precision is becoming more and more attention both at home and abroad. Based on the four channels winding ascension, we design a deviation coupling based on principle of displacement compensation control system, and use Matlab/Simulink for simulation, and research the influence law of different parameters on synchronization control accuracy. The simulation results confirmed that the strategy can satisfy the control precision. Finally, we set up the experimental system to verify the feasibility and practicability of the synchronous control system.

Abstract: Accurate material data shared in product lifecycle is the basis of manufacturing industry informationization. But material coding rule is usually different in enterprises. The code rule definition model based on code segment unit was proposed, and the segment unit was divided into four types as flow, selection, input and conversion according to code generating way. The concept of code segment structure tree was proposed to support the code method’s adaptability. The E-R model of adaptable coding system was described. The integration model of coding system, CAD, CAPP, PDM and ERP was put forward. Based on the model, generating code before design, generating code after design and generating code offline modes were proposed. Taking a specific material code rule in an enterprise as an example, the coding system’s application method was studied. The example shows that the proposed coding method is adaptable and effective.