复杂轮廓曲线的轨迹插补与速度控制方法研究-机械制造及其自动化专业论文.docxVIP

关键词：运动控制，插补，样条曲线，四元数，速度前瞻 THE RESEARCH OF INTERPOLATION AND FEEDRATE CONTROL ALGORITHM ON COMPLEX TRACK IN MACHINE TOOL MOTION CONTROL ABSTRACT Motion control technology, which determines the machining efficiency, accuracy and quality, is crucially important technology in CNC system. The CNC machine tools move towards to the direction of high speed and high accuracy. So in order to develop high performance motion controller with Chinese intellectual property rights, the thesis researches several key technologies in motion control system. In NC machining, workpiece will be decomposed into machining points list, the machine tool advances along the points track and accomplishes the machining. So how to propose the machining trajectory based on points list and how to plan the machining velocity are the keystones of this thesis. Usually, the points list can be fitted through spline curves, which can ensure the smoothness of machining surfaces, and also the points list can be connected directly using micro segment lines, which is a simpler method. Some regular complex curves, such as spiral line, can be machined according to specified algorithm without dividing it into points list. So, the literature focused on how to machine every segment between two points, how to generate the whole trajectory and how to control the velocity. Based on these questions, the thesis designed and analyzed the motion control algorithms and motion control system. And experiments are designed and implemented to validate the performance of designed system. In modern NC machining, interpolation of complex profile curve requires high speed and high accuracy. Based on B spline curve theory, this thesis presents a modified algorithm in cubic B spline curve interpolation. This proposed algorithm gives a new method which is based on pre-judgement of machining velocity to calculate the tangent vectors of spline curve junction. The tangent vectors are used to establish the spline curve equations with t