Key Engineering Materials Vols. 392-394

Abstract: Based on analyses of cutting heat and temperature in high speed milling, to construct a model of critical cutting speed for high speed milling cutter, find out influencing factor of critical cutting speed, and put forward optimization method of high speed milling cutter based on critical cutting speed. The results indicate that chip conducts a majority of cutting heat along with increase of cutting speed, feed speed and the rake of cutter. Cutting heat which workpiece conducts gradually diminishes when heat source accelerates. When cutting performance of cutter satisfies requirements of high speed milling, the proportion of cutting heat which workpiece conducts approaches its maximum as cutting speed comes to critical cutting speed. To optimize high speed face milling cutter for machining aluminum alloy according to critical cutting speed, the cutter takes on better cutting performance when cutting speed is 2040m/min~2350m/min.

Abstract: Assembly process planning automobile production line is the bridge between the design and large-scale production. It is extremely important. Not only it affects directly the assembly efficiency and the quality, moreover has decided the workshop building, the equipment investment, quantity of production personnel, goods in process quantity and so on. Whole optimization and the partial purification of the assembly craft will all have the huge economic efficiency, and obviously strengthen the emulative power of automobile production enterprise in the market. In order to optimize the result of craft planning, enhance the quality and efficiency of computer aided assembly process planning and reach expected output and efficiency, the optimizing of automobile ALB (Assembly Line Balancing) problem is deeply analyzed with linear programming theory. Besides, linear programming mathematical model of ALB problem is established. Based on the mathematical process modeling and the generation of assembly sequence and considered the relative factors between production line and process planning, basing chart of process for assembly line (PAL Chart) a modeling method is put forward. It includes the main parameters of the assembly process planning and displays the planning result directly.

Abstract: A microactuator with long-travel and high-resolution based on the principle of tribology is presented, which stroke is up to 300mm and displacement resolution is 0.01μm. It resolves the contradiction of large-stroke and high-resolution in macro/micro drive successfully. The dynamic model of the microactuator is set up. The theory analysis on the dynamic character of the system is carried out based on Karnopp “stick-slip” friction model. The physical and mathematical model of the drive part and transmission part are set up respectively by the method of modularization. The transfer function of the system is attained. The tacking simulation is carried out based on fuzzy control with speed change integral, the result is proved that error is 0.004μm.

Abstract: Process modeling of Cooperative Product Development (CPD) is the key of CPD process management. Analyzing the process of developing production based upon Petri Nets, referring to workflow management and combining with parallel project, a new workflow modeling method based upon layered timed color Petri nets is invented, which supports the developing of the model production that parallels CAD/CAPP. Finally taking the developing CDP of model product as an example, workflow model has been designed and has been inspected and verified in the software platform.

Abstract: It has been necessary to adopting automatic detection of steel ball based on machine vision in industrial processing. The detecting instrument for surface quality of steel ball based on machine vision and embedded control technique and is applied to detecting external bug region of steel ball in bearing. Its image detection and control system require excellent real-time character and high control accuracy. This paper put forward a new design for image processing and control system of detecting instrument. Firstly, we adopted OTSU segmentation arithmetic based on image enhancement and median filtering. As a result, steel ball was detected by area character parameter. Secondly, we adopted TMS320LF2407A as main processor and integrated CPLD to develop an embedded controller. It presents a novel optimal design method for PID controller based on the ant colony optimization (ACO) algorithm to optimize traditional PID control algorithm. At last, a performance study of experimental system is conducted and it shows that the proposed method can be used in online steel ball detection applications.

Abstract: In the manufacturing of diesel engine, cutting machining is the main processing method. In order to improve efficiency and increase benefit of machining, the cutting database and parameter optimization system is built for the five key parts of marine ship diesel engine, which can provide optimal and rational cutting parameters. Microsoft Visual Basic and Microsoft SQL Server 2000 are used as the database management system, combining the modeling function of Deform 5.03 software. The logical and physical models are designed, and the functions of basic information management and query are realized. It can commend reasonable cutting parameters according to machining condition input. The Weilenmann algorithm method is adopted to calculate the cutting force and motor power, and user can be convenient to judge whether the parameter input is safe and reasonable. The objective function and restrictive conditions are set up by using the simplex method and linear programming, and the optimization function of cutting parameters is realized. A developed prototype system and an example have verified some presented techniques and the research results are the basis of the future development.

Abstract: The balance of brake dish is very important for a car driving. Taking one kind of auto-equilibrium-machine of brake dish as research object, and making use of the Virtual–kind-machine technique and the ADAMS software as analysis tools, as well as with the Solid Works to set up a model, for a whole, the kinematics and dynamics of the product are analyzed in various virtual environment, the research of dynamics simulation of machine system is carried out, and various design projects are analyzed Quickly, the experiment is done, which is quite difficult to be realized by physical kind machine, after all these, an optimal design project of the system is decided. The virtual kind machine technique is applied through whole design process, thus the design of the product development becomes convenient, the development period is shortened, and the product costs are reduced so that optimal-new product can be acquired.

Abstract: The metric pump is widely used in the chemical industry and other industries which need fluid translation. It has the ability of accurate flow regulating. However, it is mainly by operating the hand wheel on the pump to regulate the flow of the pump at present. The accuracy of manual regulation is low, and the manual operated metric pump is not suitable to be used in the poisonous and dangerous circumstances. This paper chose AT89S52 as the main controller, which controlled the stepper motor. After reducing the speed by speed reducer, the stepper motor drove leadscrew to control the N-Shape Shaft, which is the flow regulating part on the pump. The system used LCD as the display unit, it can displayed the the setting values, and the values changed as the stepper motor moved. The system used 4×4 keyboard as the input interface, it has more keys which means more control funtions and inputing flow values is convenient. The experimental results indicate that the error between actual flow value and the setting value is within 2%. It reaches the factory demand. This flow regulation instrument has resloved unconvenience in manual regulation way and improved the control accuracy.

Abstract: A micro-drive device was developed to drive reflective lens frame in Inertial Confinement Fusion. The transmission consists of ball screw, flexible hinge and electrical control unit. Two different flexible hinges named straight round and cylinder interlaced flexible hinge were used in device. The communication between IPC and PLC is founded by MSComm, which realizes the distributing system. Tested on TM5 reflective lens frame of SG- III prototype facility, the precision achieved ±0.3μm/step, which meets the design target.

Abstract: A physics-based material processing simulation is approached to reveal the distortion law of aerospace monolithic components due to milling. To improve the efficiency of numerical calculation, a simplified cutting layer model is presented. The cutting force and temperature model are established to gain cutting loads. The cutting loads are applied to the mesh model of the part. The milling process of spar is simulated. Key factors influencing distortion such as initial residual stress, cutting loads, cutting sequence and tool path are considered. The total distortions of the spar are estimated. Machining experiment is carried out, and the distortion tendency of the machined part agrees well with the simulation. The results show the validity of the presented approach.