Papers by Author: Jian Guang Li

Abstract: Using MATLAB for development tools,we has developed a set of end mills CNC grinding programming system by analysis the end mills grinding craft ,research on cutter location trajectory calculation and post-processing technology. Meanwhile, build a five-axis tool grinder grinding simulation processing by VERICUT(a kind of CNC machining simulation software), through the edge grinding simulation , we confirm the cutter location trajectory and the NC code is errorless.

Abstract: With high precision special rotary tool is widely used in automotive, mold, aerospace, machinery, electronics and other fields, the demand of manufacturing for such type and quantity of cutting tool is more and more big, lead to the demand for multi-axis CNC tool grinder which provides efficient, high quality production support for it also increasing. In terms of hardware and software multi-axis CNC tool grinder in developed countries are relatively mature, but domestic did not have enough for this research, especially for development of CNC tool grinding machine operation software system, and rarely reference data. In view of the domestic manufacturer in urgent need of independent research and development of CNC tool grinder, this article will research tool grinding automatic programming and simulation technology of CNC tool grinding machine operation software system, through analyzing the four main steps of NC grinding four-blade overall end milling cutter, parametric programming with MATLAB, and grinding trajectory data in the form of mixed programming of MATLAB and VC+ + will be post processed into NC programs, then simulation in VERICUT virtual machine tool, finally the actual grinding out overall end milling cutter.

Abstract: The method of texting a blade’s aerodynamic performance used for traditional wind turbine airfoils was making pressure measurement holes on surface of the blade, but Magnus wind turbine blade must rotated at a certain speed to generate lift and drag force, so the method was inapplicable. A novel experimental device for testing aerodynamic performance of Magnus wind turbine’s cylindrical blades had been investigated. This device, which consists of three parts: cylindrical blade, controlling system and testing system, could measure the lift and drag force generated by the Magnus effect on the blades. This paper mainly studied the testing system,including dynamometer and amplifying circuit. At last, the testing system was used in the experiment to test aerodynamic performance of the Magnus wind turbine blade. The results showed that the system could conduct the experiment on testing the lift and drag force on the Magnus wind turbine blades efficiently, and the system could also be used to measure the lift and drag force on traditional wind turbine airfoil.

Abstract: Particle reinforced metal matrix composites (SiCp/Al composites) have proved to be extremely difficult to machine with traditional cutting processes due to serious tool-wear and high machining cost, which lead to the low machining efficiency. This paper presents the results of an experimental research on mill-grinding of SiC particle reinforced aluminum matrix composites. Based on the Taguchi experimental design method, study on the material removal rate was carried out to gain the optimal processing parameters combination by using the analysis of S/N ratio. The detailed effect of wheel speed on material removal rate through single factor experiment was also studied. Though analysis of S/N ratio and variance, the depth of cut has greatest effect on the material removal rate, followed by feed rate. And grinding wheel speed has least effect on it. But the depth of cut and feed rate affect on the material removal rate nonlinearly. In the range of machining parameters applied, the optimal processing parameters combination gained is A2B3C3, namely, v_s=11.77m/s, v_w=100mm/min, a_p=0.8mm. Material removal rate increased at first and then there was a decreasing trend with increasing wheel speed.

Abstract: Accuracy of the Stewart parallel manipulator is utmost important in assembly quality control procedures, and it's also difficult to demonstrate the inner relations quantitatively between errors of pose and of actuators. A novel methodology is proposed in this paper. Firstly the experiment area planning approach is proposed according to the pose and strut symmetries of the manipulator, and the uniform experiment design is conducted to investigate indexes of accuracy sensitivity. The regression equations are established to analyze the significance of various factors according to experiment results.

Abstract: In view of the present machining status of SiC particle reinforced aluminum matrix composites, the electroplated diamond wheel (80# diamond grit) was used for mill-grinding the SiC particle reinforced aluminum matrix composites and the effect of speed ratio (q) and material removal rate (MRR) on surface roughness was studied based on experiments. The experimental results show that surface roughness almost increases with the increase of speed ratio. At the same material removal rate, surface roughness increases when raising material removal rate by raising feed rate singlely or raising depth of mill-grinding singlely; surface roughness has decreasing trend with raising material removal rate by increasing feed rate and depth of mill-grinding at the same time.

Abstract: An improved algorithm, dynamic collision detection with optimum discrete interval is presented to improve the efficiency of dynamic collision detection. The algorithm based on the minimum distance between two objects with relative movement to determine the next discrete position, on which collision or interference is free. The method using the minimum distance as discrete interval to determine the next interference-free position makes each interval longest under the constraint of safety so that the reliability between the moving object-pair is ensured while the efficiency is improved. The practical demonstration has proved that the improved algorithm is capable of high performance than that of the collision detection method with even discrete interval. This algorithm has been successfully used in a verification system of inspection process by secondary development of Pro/Engineer.

Abstract: Cutting parameters play an essential role in the economics of machining. In this paper, particle swarm optimization (PSO), a novel optimization algorithm for cutting parameters optimization (CPO), was discussed comprehensively. First, the fundamental principle of PSO was introduced; then, the algorithm for PSO application in cutting parameters optimization was developed; thirdly, cutting experiments without and with optimized cutting parameters were conducted to demonstrate the effectiveness of optimization, respectively. The results show that the machining process was improved obviously.

Abstract: Due to cutting parameters playing an important role in machining economics and machining qualities, much attention has been paid to select optimum cutting parameters. In this paper, cutting parameters optimization for constant cutting force was discussed based-on virtual machining comprehensively. Particle swarm optimization (PSO) was used to seek for the optimal spindle speed and feed rate. The framework of virtual machining based cutting parameters optimization was established. Then two controlled experiments were conducted to demonstrate the effectiveness of cutting parameters optimization both with physical cutting and computer simulation. The results of experiments show that machining process with constant cutting force can be achieved via cutting parameters optimization based on virtual machining.

Abstract: Virtual manufacturing (VM), which primarily aimed at reducing the lead times to market and costs associated with new product development, offers various test-beds for the time-consuming and expensive physical experimentation. Since surface roughness and form accuracy play essential roles in the functional performance of the products machined with ultra-precision machining technology. An optimizer, VSPDT (virtual single point diamond turning) system was developed for the purpose of form error compensation and optimal cutting parameters selection. In this paper, the keys issues for developing VSPDT using virtual manufacturing technology were highlighted such as framework of system, virtual workpiece, virtual machining and inspection, etc. At the end of the paper, A VSPDT was developed and applied to predict and compensate the form error, select optimal cutting parameters by using a 2-axis CNC ultra-precision turning machine.