Papers by Keyword: Swept Volume

Abstract: In this paper, a novel approach of linear octree is employed to represent discrete tools and build their swept volumes along machining trajectories. Firstly, a data structure of linear octree is defined as the base of geometrical transformations. The linear octree can be extended into leaf nodes in the deepest level for simplifying homogeneous transformations, and all leaf nodes in the deepest level can also be concentrated into a linear octree for saving storage capacity inversely. Secondly, tool trajectories are interpolated as short lines, and swept volumes between neighbor interpolation points are defined as the Minkowski sum of their cell sets at both locations. Thirdly, equations of the rotation matrix for local coordinate system, roll, pitch and yaw angles of tool orientations are established to define the global rotation motions. Finally, a case of discrete sphere tool and its swept volume modeling are studied to validate the proposed approach.

Abstract: The performance of two kinds of functional polymers were evaluated by lab experiments. Furthermore, relationship between viscosity and concentration, viscosity stability, flow characteristics of two kinds of functional polymers are studied. The results show that two functional polymers have a higher viscosity at different concentrations. The viscosity of functional polymer increases with the time. Flow characteristics show that functional polymers have a higher drag coefficient and residual resistance factor. Meanwhile, we conducted displacement efficiency experiments and expand swept volume experiments. The studies show that two kinds of functional polymer provide significant improvement in displacement efficiency, and after conventional polymer flooding, it also can expand swept volume of low permeability layers effectively.

Abstract: Five-axis NC machining tools can improve the efficiency and accuracy obviously in today’s machining industries, but the machining errors and tool interference are likely to happen due to the complexity of tool motion. So the verification of the tool path is very important and necessary before machining the part. A new algorithm for 5-axis machining verification based on the swept volume has been presented in the paper. Based on the machine tool path and the cutter geometry, the cutter’s instantaneous swept profile is determined. By integrating the intermediate swept volume, the cutter’s swept envelope can be constructed and applied to NC verification. The algorithm has been implemented through Visual C++ and OpenGL language on Windows XP platform; a few examples are to verify the reliability of the proposed algorithms effectively. The experiment results indicate that the proposed method is superior to the traditional methods on the processing time and image quality. This proposed algorithm can be further applied to machining error analysis, collisions interference and NC path optimization, etc.