Key Engineering Materials Vols. 392-394

Abstract: The subject study uses ceramic materials as a circular burnishing-tool connected with a ring-form electrode to construct a compound circular finishing-tool. In the machining process, the external cylindrical workpiece is put into the compound circular finishing-tool to execute the finishing process by automatic continuity production. By the compound production effects from the electrode and the burnishing-tool, it achieves synchronous execution of multiple effects of electrochemical finishing and burnishing. Thereby rapidly and highly efficiently making improvement on the surface roughness of external cylindrical surface; and by the burnishing process and electrochemical finishing, it enhances the mechanical properties and cleanliness on the materials surface. It is expected that the entire study could make a comprehensive assessment of the compound process characteristics of the circular burnishing-tool and automatic continuity synchronous burnishing and electrochemical finishing, seeking the optimal electrode design and experimental parameters, so that polishing techniques for the external cylindrical can be extensively applied in the future.

Abstract: In free-form surface machining, it is essential to optimize the feedrate in order to improve the machining efficiency. Conservative constant feedrate values have been mostly used since there was a lack of physical models and optimization tools for the machining processes. The overall goal of this research is the integration of geometric and mechanistic milling models for force prediction and feedrate scheduling for free-form surface machining. For each tool move a geometric model calculates the cutting geometry parameters, then a mechanistic model uses this information with the constraint force to calculate desired feedrates. The feedrate is written into the part program. When the integrated modeling approach was used, it was shown that the machining time can be decreased significantly along the tool path. Production time in machining propeller example was reduced to 35% compared to constant feedrate cases.

Abstract: Manufacturing process is an important aspect in the implementation of Green manufacturing, the comprehensive evaluation of manufacturing process resources and environmental attributes can effectively guide its green improving. A comprehensive evaluation model of manufacturing process resources and environmental attributes based on B-P neural network is established, which is closer to human thinking model and integrates qualitative and quantitative analysis. The structure and solving of the model are studied as well as the quantification method of network input indexes. The case application proved the correctness and validity of the method.

Abstract: The development of a novel amphibian walking robot prototype is proposed according to the need of duty under bad circumstance. It can be used as the carrier of the reconnaissance equipment, the weapon system and the communication system, and complete many kinds of missions in the place near the sea and tideland which a man can not complete. Some new dynamics questions is introduced because of multi-leg structure features and functionality of the amphibious. The integrated approach of series parallel is proposed to solve the characteristic that swing and supporting phase are appeared respectively during walking. Hydrodynamic effect is also considered in our dynamics equation. At last, the least distribution model of driving moment and driving energy of robot are set up in this paper. These conclusions have very important effects to the control of robots.

Abstract: This paper depicts a boring and trepanning association (BTA) deep-hole drilling system with near-dry cutting technique. The cutting tests are carried out in view of the machining performances under the condition of applying the compressed air and atomized cutting fluid for drilling deep holes on titanium alloy which is difficult to cut. Several cutter materials have been utilized in the tests. The reasonable material of the deep-hole drilling cutter has been determined by analyzing the cutting force, the cutter wear and the surface finish. Environmental pollution decreases owing to little cutting fluid consumption in near-dry cutting system.

Abstract: This paper analyzed the current process planning based on 3D feature model, and pointed out the exiting disadvantages. The framework and key technologies that play a vital role in process planning were issued. A uniform manufacturing model, which was built on component model by offsetting surface features and volumetric features. It implemented the typical machining features recognition and extraction, including visional entity and conceal technological attribute. It also set up hierarchy planning model. Under the support of these theories, a feature-oriented process planning generation system based on Solidworks CAD platform was developed. With the testing work on the interrelated examples, the software system has validated the feasibility and practicability of the method in this paper, which will enrich the way to make stock model in existent CAM software system. It has significant meaning to promote the integration of CAD/CAPP.

Abstract: Spool valve orifice flow characteristic of servo valve plays an important role in the spool valve overlap measurement and manufacturing quality analysis of servo valve. The liner segment of flow characteristic curve could be used to calculate the overlap, and the non-linear segment could be used to evaluate the manufacturing quality of servo valve. This paper analyzed the valve orifice characteristic measurement based on the pneumatic flow method in detail, developed an automatic pneumatic measurement apparatus for valve orifice characteristic and spool valve overlap based on the thermal mass flow sensor AWM2300, verified the measurement accuracy and non-repeated error of this apparatus, and adopted the overlap as investigated object to contrast the measurement results by pneumatic flow method with by pneumatic pressure method. The non-repeated error of overlap measurement by pneumatic flow method did not exceed ±0.5(m, and the experimental results indicated that the automatic pneumatic flow measurement can excellently satisfy the actual requirement in the production of servo valve.

Abstract: Theoretical models of temperature field are presented from Beer-Lambert law. This paper uses Beer-Lambert law to calculate powder flow on the absorption of energy and applies the law of the conservation of the energy to calculate the temperature of powder stream. This paper analyzes the effect of the various factors on the temperature field of powder flow. Temperature field of powder stream is measured by CCD camera. Finally the comparison of the theoretical results and the experimental results indicates the accuracy of the theoretical calculation.

Abstract: This paper considers the practical manufacturing environment of the hybrid flow shop (HFS) with non-identical machines in parallel. In order to significantly enhance the performance level of manufacturing, maintaining load balancing among parallel machines is very important. The aim of this paper is to minimize makespan with load balancing in a non-identical parallel machine environment by using hybrid genetic algorithm (HGA). In the HGA, the neighborhood search-based method is used together with genetic algorithm as local optimization method to balance the exploration and exploitation abilities. The representation of chromosome used in this paper is composed of two layers: allocation layer and sequencing layer, which can be encode and decoded easily. In generating initial population, a special constraint of load balancing between parallel machines is used to reduce the number of individuals. And particular crossover operation is used, which generates multiple offspring at a time, so that the efficiency of the algorithm can be well improved. At last, the proposed algorithm is tested on a benchmark, and numerical example shows good result.

Abstract: Box-like components are the component class with the complexity in structure and shape, and required premium quality on the machined surfaces, and with difficulty in design and manufacturing. In Euclid Space, a 3D modeling with collection of feature information based mainly on the CSG fundamental geometric element method and topological relationship was presented, with fundamental geometric element set, the topological relationship tree and datum system of fundamental geometric elements, and Boolean operations and linking, for CSG modeling of common box-like components. Details were also given to the study and construction of 9 modules for feature information collection. CSG modeling and collection of feature information of a base-box of reduction unit were put forward, as an example. The initial application of the system has shown that it was of simplicity, intuition, and effectiveness, with plenty feature pieces of feature information. It is satisfactory to design digitally even more complicated box-like components, and build up the information base for the following digital engineering with the current system.