Quan Yanming

Tool wear and its mechanism for cutting SiC particle-reinforced aluminium matrix composites

Abstract Tool wear in the cutting of SiC particle-reinforced aluminium matrix composites has been investigated with special attention paid to the effects of material structures on the tool wear mechanism. The results of experiments show that the major damage mechanism is abrasive wear for conventional tools and brittle break for high hardness tools in the cutting of SiC particle-reinforced aluminium matrix composites. Even though a built-up edge can occur on the face of the tool at a lower cutting speed, it cannot protect the flank face of the tool from abrasive wear. The volume fraction and the size of SiC particle are found to be the major factors affecting the tool life. When the composites are cut by conventional tools or by most ceramic tools, SiC particles in the composites also micro-cut these tools due to their high hardness. However, when the size of SiC is fine enough, the matrix of the composites coordinates the particle into deformation. Thus, it is concluded that the cutting of composites reinforced by coarse SiC particles requires tools which have high hardness: conventional tools are only adaptable to cut composites reinforced by fine SiC particles.

Study on the adaptability of thick film diamond tool to cutting composites

In order to explore the adaptability of a thick film diamond tool to the finish machining of composites, tool wear and its effect factors as well the machined surface roughness are investigated in this paper. The experimental results show that the thick film diamond tool has a low wear rate and the machined surface cut with the tool has a fine finish for the cutting of composites. The negative rake is beneficial for the tool standing wear and collision.

Trajectory Planning of Robot Based on Quantum Genetic Algorithm

There are many possible trajectories between the given points in Euclidean geometry space for industrial robots. Under constraints of robotic kinematics or dynamics, the optimization of robotic running time is required. In this paper, a trajectory planning method of robot based on quantum genetic algorithm is proposed. Firstly, cubic B-spline function and constraint condition of robotic kinematics were introduced. Then, the chromosome and evolutionary update strategy in quantum genetic algorithm were described, and the variable fitness function of trajectory planning was also defined. Finally, the methods and procedures were introduced in detail, and the first three joint trajectories and the quantum genetic algorithm were programmed on MATLAB platform. The simulation experiments showed that trajectories of joint displacement, velocity, acceleration and jerk could be obtained effectively. The results verified the reliability and practicability of the method.

Workpiece Posture Measurement and Intelligent Robot Grasping Based on Monocular Vision

Industrial robots have been widely applied in grasping static workpieces, but the measurement method for the three-dimensional position of known specifications and random location of online workpieces still cannot meet the application requirements of the industrial field. In this paper, system structure and installation design of hardware were introduced firstly. Then, image pre-processing and feature extraction were established, composing of image enhancement, image smooth, edge detection, corner detection and angle calculation. Finally, a monocular vision-guided robot grasping device platform was established as well as corresponding software control platform. Experimental results indicated that the monocular vision system could quickly identify the workpiece pose with high measurement accuracy and that the robot could successfully grasp random location workpieces.

An Improved Fast Self-Comparison Algorithm for High-Speed Defect Detection of ITO Circuits

For PCTP ITO circuit defect detection based on template matching, usually the templates in DXF format cannot be used directly. Because the sensed images will be deformed, then the effectiveness of comparison algorithm will be adversely affected. Based on FFT a self-comparison algorithm for high-speed defect detection of ITO circuit in PCTP is developed in which a faultless template is extracted from sensed images. 1-D FFT and 2-D FFT are compared for the practicability, and the effectiveness of the algorithm is analyzed for the detection of sensed images with different brightness. The experiment results show this algorithm is applicable and fast.